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ADVANCES INECONOMETRICS - THEORYAND APPLICATIONSEdited by Miroslav Verbič


Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> ApplicationsEdited by Miroslav VerbičPublished by InTechJaneza Trd<strong>in</strong>e 9, 51000 Rijeka, CroatiaCopyright © 2011 InTechAll chapters are Open Access articles distributed under the Creative CommonsNon Commercial Share Alike Attribution 3.0 license, which permits to copy,distribute, transmit, <strong>and</strong> adapt the work <strong>in</strong> any medium, so long as the orig<strong>in</strong>alwork is properly cited. After this work has been published by InTech, authorshave the right to republish it, <strong>in</strong> whole or part, <strong>in</strong> any publication <strong>of</strong> which theyare the author, <strong>and</strong> to make other personal use <strong>of</strong> the work. Any republication,referenc<strong>in</strong>g or personal use <strong>of</strong> the work must explicitly identify the orig<strong>in</strong>al source.Statements <strong>and</strong> op<strong>in</strong>ions expressed <strong>in</strong> the chapters are these <strong>of</strong> the <strong>in</strong>dividual contributors<strong>and</strong> not necessarily those <strong>of</strong> the editors or publisher. No responsibility is acceptedfor the accuracy <strong>of</strong> <strong>in</strong>formation conta<strong>in</strong>ed <strong>in</strong> the published articles. <strong>The</strong> publisherassumes no responsibility for any damage or <strong>in</strong>jury to persons or property aris<strong>in</strong>g out<strong>of</strong> the use <strong>of</strong> any materials, <strong>in</strong>structions, methods or ideas conta<strong>in</strong>ed <strong>in</strong> the book.Publish<strong>in</strong>g Process Manager Iva LipovicTechnical Editor Teodora SmiljanicCover Designer Jan HyratImage Copyright szefei, 2010. Used under license from Shutterstock.comFirst published July, 2011Pr<strong>in</strong>ted <strong>in</strong> CroatiaA free onl<strong>in</strong>e edition <strong>of</strong> this book is available at www.<strong>in</strong>techopen.comAdditional hard copies can be obta<strong>in</strong>ed from orders@<strong>in</strong>techweb.orgAdvances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications, Edited by Miroslav Verbičp. cm.ISBN 978-953-307-503-7


free onl<strong>in</strong>e editions <strong>of</strong> InTechBooks <strong>and</strong> Journals can be found atwww.<strong>in</strong>techopen.com


ContentsPreface VIIPart 1 Recent Advances <strong>in</strong> Econometric <strong>The</strong>ory 1Chapter 1Chapter 2Chapter 3<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong><strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces 3Graciela <strong>Chichilnisky</strong>Instrument Generat<strong>in</strong>g Function <strong>and</strong>Analysis <strong>of</strong> Persistent EconomicTimes Series: <strong>The</strong>ory <strong>and</strong> Application 19Tsung-wu HoRecent Developments <strong>in</strong> SeasonalVolatility Models 31Julieta Frank, Melody Ghahramani <strong>and</strong> A. ThavaneswaranPart 2 Recent Econometric Applications 45Chapter 4Chapter 5Chapter 6<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>gPrograms on the Labor Market Transitions <strong>of</strong>Disadvantaged Men 47Lucie Gilbert, Thierry Kamionka <strong>and</strong> Guy LacroixReturns to Education <strong>and</strong> Experience With<strong>in</strong> the EU: AnInstrumental Variable Approach for Panel Data 79Inmaculada García-Ma<strong>in</strong>ar <strong>and</strong> Víctor M. Montuenga-GómezUs<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong>for Neighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway 97A. Khalik Salman


PrefaceEconometrics is a (sub)discipl<strong>in</strong>e <strong>of</strong> economics concerned with the development <strong>of</strong>economic science <strong>in</strong> l<strong>in</strong>e with mathematics <strong>and</strong> statistics. <strong>The</strong>oretical econometricsstudies statistical properties <strong>of</strong> econometric procedures; applied econometrics <strong>in</strong>cludesthe application <strong>of</strong> econometric methods to assess economic theories <strong>and</strong> the development<strong>and</strong> use <strong>of</strong> econometric models. <strong>The</strong> term “econometrics” first appeared one centuryago, while the discipl<strong>in</strong>e really got the momentum <strong>in</strong> the 1930s with the found<strong>in</strong>g<strong>of</strong> Econometric Society. Nowadays, econometrics is becom<strong>in</strong>g a highly developed <strong>and</strong>highly mathematicized array <strong>of</strong> its own (sub)discipl<strong>in</strong>es. And it should be this way, aseconomies are becom<strong>in</strong>g <strong>in</strong>creas<strong>in</strong>gly complex, <strong>and</strong> scientific economic analyses requireprogressively thorough knowledge <strong>of</strong> solid quantitative methods. This was especiallyobvious dur<strong>in</strong>g the recent global f<strong>in</strong>ancial <strong>and</strong> economic crisis. As my graduatepr<strong>of</strong>essor <strong>of</strong> econometrics, Dr. Jan F. Kiviet used to say: “Economics deserves hardmethods.” This book thus provides a recent <strong>in</strong>sight on some key issues <strong>in</strong> econometrictheory <strong>and</strong> applications.<strong>The</strong> first three chapters focus on recent advances <strong>in</strong> econometric theory. <strong>The</strong> first chapterexplores non-parametric (<strong>NP</strong>) estimation with a priori assumptions on neither thefunctional relations nor on the observed data. This appears to be the most general possibleform on the purpose <strong>of</strong> econometrics; f<strong>in</strong>d<strong>in</strong>g the functional form that underliesthe data without mak<strong>in</strong>g a priori restrictions or assumptions that can bias the search.In seek<strong>in</strong>g the boundaries <strong>of</strong> the possible, one runs aga<strong>in</strong>st a sharp divid<strong>in</strong>g l<strong>in</strong>e thatdef<strong>in</strong>es a necessary <strong>and</strong> sufficient condition for successful <strong>NP</strong> estimation. This conditionis denom<strong>in</strong>ated “<strong>The</strong> limits <strong>of</strong> econometrics”, <strong>and</strong> it is found somewhat surpris<strong>in</strong>glythat it is equal to the classic statistical assumption on the relative likelihood <strong>of</strong>bounded <strong>and</strong> unbounded events.<strong>The</strong> second chapter considers the traditional approach to the persistence properties <strong>of</strong>time series, i.e. the unit root test<strong>in</strong>g <strong>and</strong> the median-unbiasedness method. <strong>The</strong> latter isused to estimate e.g. the AR(1) coefficients to <strong>in</strong>vestigate the persistence behaviour,due to the near unit root bias <strong>and</strong> result<strong>in</strong>g lack <strong>of</strong> distribution. Here it is shown that <strong>in</strong>order to calculate half-life from an AR(1) model, the <strong>in</strong>strument generat<strong>in</strong>g function(IGF) estimator is not only an asymptotically normal estimator, but also an easy-to-usealternative to the median-unbiasedness approach. An unrestricted FM-AR(p) model isproposed, a slight extension <strong>of</strong> the FM-VAR method, to estimate coefficients directly.


VIIIPreface<strong>The</strong> third chapter proposes various classes <strong>of</strong> seasonal volatility models. Time seriesprocesses are considered, such as AR <strong>and</strong> RCA processes, with multiplicative seasonalGARCH errors <strong>and</strong> SV errors. <strong>The</strong> multiplicative seasonal volatility models are suitablefor time series where autocorrelation exists at seasonal <strong>and</strong> at adjacent nonseasonallags. <strong>The</strong> models <strong>in</strong>troduced here extend <strong>and</strong> complement the exist<strong>in</strong>g volatilitymodels <strong>in</strong> the literature to seasonal volatility models by <strong>in</strong>troduc<strong>in</strong>g more generalstructures.<strong>The</strong> last three chapters are dedicated to recent econometric applications. <strong>The</strong> fourthchapter focuses on the impacts <strong>of</strong> government-sponsored tra<strong>in</strong><strong>in</strong>g programs aimed atdisadvantaged male youths on their labour market transitions. A cont<strong>in</strong>uous time durationmodel is applied to estimate the density <strong>of</strong> duration times, controll<strong>in</strong>g for theendogeneity <strong>of</strong> an <strong>in</strong>dividual’s tra<strong>in</strong><strong>in</strong>g status. <strong>The</strong> sensitivity <strong>of</strong> parameter estimates is<strong>in</strong>vestigated by compar<strong>in</strong>g a typical non-parametric specification <strong>and</strong> a series <strong>of</strong> parametrictwo-factor load<strong>in</strong>g models. <strong>The</strong>se models implicitly assume that the <strong>in</strong>tensity<strong>of</strong> transitions is related to the state <strong>of</strong> dest<strong>in</strong>ation. Additionally, a parametric threefactorload<strong>in</strong>g model is estimated. <strong>The</strong> novelty <strong>of</strong> this specification lies <strong>in</strong> the fact thatthe <strong>in</strong>tensities <strong>of</strong> transitions are related to both the state <strong>of</strong> dest<strong>in</strong>ation <strong>and</strong> the state <strong>of</strong>orig<strong>in</strong>.<strong>The</strong> fifth chapter extends the exist<strong>in</strong>g research on the returns to human capital accumulationthat differentiates between the self-employed <strong>and</strong> wage earners. This is carriedout by provid<strong>in</strong>g evidence <strong>in</strong> a cross-country framework us<strong>in</strong>g a homogenous database,which mitigates the problems associated with the existence <strong>of</strong> different datasources across countries, by us<strong>in</strong>g a panel data approach that is useful <strong>in</strong> deal<strong>in</strong>g withendogeneity <strong>and</strong> selectivity biases, as well as unobserved heterogeneity, <strong>and</strong> by apply<strong>in</strong>gan efficient estimation method that allows for the correlation between <strong>in</strong>dividualeffects <strong>and</strong> time-<strong>in</strong>variant regressors, <strong>and</strong> that avoids the <strong>in</strong>security associated withthe choice <strong>of</strong> the appropriate <strong>in</strong>struments.<strong>The</strong> last chapter <strong>in</strong>vestigates the <strong>in</strong>ternational dem<strong>and</strong> for tourism <strong>in</strong> two neighbour<strong>in</strong>gSc<strong>and</strong><strong>in</strong>avian regions by specify<strong>in</strong>g separate equations that <strong>in</strong>clude the relevant <strong>in</strong>formation.A period <strong>of</strong> transition is analyzed from lower levels <strong>of</strong> <strong>in</strong>tegration to more<strong>in</strong>tense <strong>in</strong>tegration, globalization, competitiveness, <strong>and</strong> high levels <strong>of</strong> <strong>in</strong>come <strong>and</strong> welfare.Instead <strong>of</strong> be<strong>in</strong>g estimated equation-by-equation us<strong>in</strong>g st<strong>and</strong>ard ord<strong>in</strong>ary leastsquares, which is a consistent estimation method, the equations are estimated us<strong>in</strong>gthe generally more efficient iterative seem<strong>in</strong>gly unrelated regression (ISUR) approach,which amounts to feasible generalized least squares with a specific form <strong>of</strong> the variance-covariancematrix.<strong>The</strong> book conta<strong>in</strong>s up-to-date publications <strong>of</strong> lead<strong>in</strong>g experts. <strong>The</strong> references at the end<strong>of</strong> each chapter provide a start<strong>in</strong>g po<strong>in</strong>t to acquire a deeper knowledge on the state <strong>of</strong>the art. <strong>The</strong> edition is <strong>in</strong>tended to furnish valuable recent <strong>in</strong>formation to the pr<strong>of</strong>essionals<strong>in</strong>volved <strong>in</strong> develop<strong>in</strong>g econometric theory <strong>and</strong> perform<strong>in</strong>g econometric applications.


PrefaceIXLastly, I would like to thank all the authors for their excellent contributions <strong>in</strong> differentareas covered by this book, <strong>and</strong> the InTech team, especially the process manager Ms.Iva Lipović, for their support <strong>and</strong> patience dur<strong>in</strong>g the whole process <strong>of</strong> creat<strong>in</strong>g thisbook. I dedicate this book to my mother Ana Verbič <strong>and</strong> my recently deceased fatherMiroslav Verbič.Miroslav VerbičUniversity <strong>of</strong> Ljubljana,Slovenia


Part 1Recent Advances <strong>in</strong> Econometric <strong>The</strong>ory


10<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong><strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert SpacesGraciela <strong>Chichilnisky</strong>*Columbia University, New YorkUSA1. IntroductionNon-Parametric (<strong>NP</strong>) estimation seeks the most general way to f<strong>in</strong>d a functional form that fitsobserved data. Any parametric assumption places a somewhat unnatural apriori restrictionon the problem. For example l<strong>in</strong>ear estimation assumes from the outset that the functionalforms described by the data are l<strong>in</strong>ear. This is a strong assumption that is <strong>of</strong>ten <strong>in</strong>correct <strong>and</strong>prevents us from see<strong>in</strong>g the essential non-l<strong>in</strong>ear nature <strong>of</strong> economics. Indeed market clear<strong>in</strong>gconditions are typically non-l<strong>in</strong>ear <strong>and</strong> therefore market behavior is not properly describedby l<strong>in</strong>ear equations. Parametric estimation is therefore a "straight-jacket" that limits or distortsour perception <strong>of</strong> the world.But how general is the <strong>NP</strong> philosophy? How far does it go? Are there limits to <strong>NP</strong> econometricestimation, can we assume noth<strong>in</strong>g at all about the parameters <strong>of</strong> the problem <strong>and</strong> still obta<strong>in</strong>successful statistical tests that disclose the funcional forms beh<strong>in</strong>d the observed data? Thischapter explores the limits to our ability to extend <strong>NP</strong> estimation. Consider<strong>in</strong>g the success<strong>of</strong> <strong>NP</strong> estimation <strong>in</strong> bounded or compact doma<strong>in</strong>s, the chapter seeks ways to identify thelimits <strong>of</strong> extend<strong>in</strong>g it from bounded <strong>in</strong>tervals to the entire real l<strong>in</strong>e R + , so as to avoid artificialconstra<strong>in</strong>ts that contradict the <strong>in</strong>tention <strong>of</strong> <strong>NP</strong> estimation. <strong>The</strong> bounded sample approachis not new. In 1985 Rex Bergstrom (1985) constructed a non - parametric (<strong>NP</strong>) estimator fornon-l<strong>in</strong>ear models with bounded sample spaces, us<strong>in</strong>g techniques <strong>of</strong> Hilbert spaces 1 atype<strong>of</strong> space I <strong>in</strong>troduced <strong>in</strong> Economics (<strong>Chichilnisky</strong>, 1977). His article is simple, elegant <strong>and</strong>general, but requires an aprioribound on observed data that conflicts with the spirit <strong>of</strong> <strong>NP</strong>estimation. This chapter extends these orig<strong>in</strong>al results to unbounded sample spaces such asthe positive real l<strong>in</strong>e R + , 2 us<strong>in</strong>g earlier work (<strong>Chichilnisky</strong> 1976, 1977, 1996, 2000, 2006, 2009,2010a, 2010b <strong>and</strong> 2011). We f<strong>in</strong>d a sharp divid<strong>in</strong>g l<strong>in</strong>e, a condition that is both necessary <strong>and</strong>sufficient for extend<strong>in</strong>g <strong>NP</strong> estimation from bounded <strong>in</strong>tervals to the entire real l<strong>in</strong>e. <strong>The</strong> clue*UNESCO Pr<strong>of</strong>essor <strong>of</strong> <strong>Mathematics</strong> <strong>and</strong> Economics, <strong>and</strong> Director, Columbia Consortium for RiskManagement, Columbia University, New York. This chapter was based on an <strong>in</strong>vited address at aconference at the University <strong>of</strong> Essex <strong>in</strong> May 2006, honor<strong>in</strong>g Rex Bergstrom’s memory. I thank theparticipants for valuable comments <strong>and</strong> particularly Peter Phillips, the organizer. I am also gratefulto William Barnett <strong>of</strong> the University <strong>of</strong> Kansas, the participants <strong>of</strong> a Statistics Department sem<strong>in</strong>ar atColumbia University, the Econometrics Sem<strong>in</strong>ar at the Economics Department <strong>of</strong> Columbia University,<strong>and</strong> particularly Victor De La Pena, Chris Heyde, Marc Henry <strong>and</strong> Dennis Kristensen, for helpfulcomments <strong>and</strong> suggestions.


<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong><strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces 3<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong> <strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces5This provides a natural <strong>in</strong>f<strong>in</strong>ite dimensional context for <strong>NP</strong> estimation. In this context, Hilbertspaces are a natural choice, because they are the closest analog to Euclidean space <strong>in</strong> <strong>in</strong>f<strong>in</strong>itedimensions.Bergstrom (1985) po<strong>in</strong>ted out that there is a natural limitation for the use <strong>of</strong> Hilbert spaceon the real l<strong>in</strong>e R. St<strong>and</strong>ard Hilbert spaces such as L 2 (R) require that the unknown functionapproaches zero at <strong>in</strong>f<strong>in</strong>ity, a somewhat unreasonable limitation to impose on the economicmodel as they exclude widely used functions such as constant, <strong>in</strong>creas<strong>in</strong>g <strong>and</strong> cyclicalfunctions on the l<strong>in</strong>e. To overcome his objection I suggested us<strong>in</strong>g weighted Hilbert spacess<strong>in</strong>ce these impose weaker limit<strong>in</strong>g requirement at <strong>in</strong>f<strong>in</strong>ity as shown below. Bergstrom’sarticle (1985) acknowledged my contribution to <strong>NP</strong> estimation <strong>in</strong> Hilbert spaces, but it isrestricted to bounded sample spaces: his results apply to L 2 spaces <strong>of</strong> functions def<strong>in</strong>ed ona bounded segment <strong>of</strong> the l<strong>in</strong>e, [a, b] ⊂ R.Below we extend the orig<strong>in</strong>al methodology <strong>in</strong> Bergstrom (1985) to unbounded sample spacesby us<strong>in</strong>g weighted Hilbert spaces as I orig<strong>in</strong>ally proposed. In explor<strong>in</strong>g the viability <strong>of</strong> thepro<strong>of</strong>s, we run <strong>in</strong>to an <strong>in</strong>terest<strong>in</strong>g dilemma. When the sample space is the entire positive reall<strong>in</strong>e, Hilbert space techniques still require additional conditions on the asymptotic behavior<strong>of</strong> the unknown function at <strong>in</strong>f<strong>in</strong>ity. In bounded sample spaces such as [a, b] this problemdid not arise, because the unknown are cont<strong>in</strong>uous, <strong>and</strong> therefore bounded <strong>and</strong> belong to theHilbert space L 2 [a, b]. But this is not the case when the sample space is the positive l<strong>in</strong>e R + .A cont<strong>in</strong>uous real valued function on R + may not be bounded, <strong>and</strong> may not be <strong>in</strong> the spaceL 2 (R + ) 5 . <strong>The</strong>refore the Fourier series expansions that are used for def<strong>in</strong><strong>in</strong>g the estimator maynot converge. With unbounded sample spaces, additional statistical assumptions are neededfor <strong>NP</strong> estimation.Consider the problem <strong>of</strong> estimat<strong>in</strong>g an unknown function f on R + , for example a capitalaccumulation path through time or a density function, which are st<strong>and</strong>ard non - l<strong>in</strong>ear <strong>NP</strong>estimation problems. <strong>The</strong> unknown density function may be cont<strong>in</strong>uous, but not a square<strong>in</strong>tegrable function on R + namely an element <strong>of</strong> L 2 (R + ).S<strong>in</strong>cethe<strong>NP</strong> estimator is def<strong>in</strong>edby approximat<strong>in</strong>g values <strong>of</strong> the Fourier coefficients <strong>of</strong> the unknown function (Berhstrom1985), when the Fourier coefficients <strong>of</strong> the estimator do not converge, the estimator itselffails to converge. A similar situation arises <strong>in</strong> general <strong>NP</strong> estimation problems where theunknown function may not have the asymptotic behavior needed to ensure the appropriateconvergence. This illustrates the difficulties <strong>in</strong>volved <strong>in</strong> extend<strong>in</strong>g <strong>NP</strong> estimation <strong>in</strong> Hilbertspaces from bounded to unbounded sample spaces.<strong>The</strong> rest <strong>of</strong> this chapter focuses on statistical necessary <strong>and</strong> sufficient conditions needed forextend<strong>in</strong>g the results from bounded <strong>in</strong>tervals to the positive l<strong>in</strong>e R. +3. Statistical assumptions <strong>and</strong> <strong>NP</strong> estimationA brief summary <strong>of</strong> earlier work is as follows. Bergstrom’s statistical assumptions (Bergstrom,1985) require that the unknown function f be cont<strong>in</strong>uous <strong>and</strong> bounded a.e. on the samplespace [a, b] ∈ R. 6 His sample design assumes separate observations at equidistant po<strong>in</strong>ts. <strong>The</strong>number <strong>of</strong> parameters <strong>in</strong>creases with the size <strong>of</strong> the sample space, <strong>and</strong> disturbances are notnecessarily normal.Bergstrom uses an orthogonal series <strong>in</strong> Hilbert space to derive <strong>NP</strong> properties <strong>and</strong> proveconvergence theorems. <strong>The</strong> series is orthonormal <strong>in</strong> the Hilbert space rather than <strong>in</strong> the sample


6 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications4 Will-be-set-by-IN-TECHspace, so the elements rema<strong>in</strong> unchanged as the sample size <strong>in</strong>creases. This series <strong>in</strong>cludespolynomials or any dense family <strong>of</strong> orthonormal functions <strong>in</strong> the Hilbert space.∧An estimator f is def<strong>in</strong>ed <strong>in</strong> a simple <strong>and</strong> natural manner (Bergstrom 1985): the first MFourier coefficients <strong>of</strong> the unknown function f are estimated relative to the orthonormalset. Estimates <strong>of</strong> the coefficients are obta<strong>in</strong>ed from the sample by ord<strong>in</strong>ary least squaresregression,[sett<strong>in</strong>g the rest]<strong>of</strong> the Fourier coefficients to zero. Bergstrom (1985) shows that∫ bE a {∧ f MN(x) − f (x)}dx can be made arbitrarily small by a suitable choice <strong>of</strong> M <strong>and</strong> <strong>of</strong> N.He also def<strong>in</strong>es an estimator fN ∗ (x) that is optimal for the sample size N, <strong>and</strong> shows that thisconverges <strong>in</strong> a given metric to f (x) as N → ∞. A third theorem shows how an optimal value <strong>of</strong>M ∗ is related to the Fourier coefficients <strong>and</strong> the mean square errors <strong>of</strong> their estimates obta<strong>in</strong>edfrom regressions with various values <strong>of</strong> M, <strong>and</strong> provides the basis for an estimation procedure.A "stopp<strong>in</strong>g rule" is also provided for estimat<strong>in</strong>g the optimum value <strong>of</strong> the parameter which,for a given sample, provides the exact number <strong>of</strong> Fourier coefficients to be estimated. <strong>The</strong>def<strong>in</strong>ition <strong>of</strong> the estimator <strong>and</strong> the pro<strong>of</strong>s <strong>of</strong> these results require that f be an element <strong>of</strong> aHilbert space.Unbounded sample spaces give rise to a different type <strong>of</strong> problem. To expla<strong>in</strong> the problem<strong>and</strong> motivate the results we first expla<strong>in</strong> why earlier work was restricted to bounded samplespaces.4. Why bounded sample spaces?When work<strong>in</strong>g <strong>in</strong> Hilbert spaces, there are good technical reasons for requir<strong>in</strong>g that thesample space be bounded. For example, consider the typical Hilbert space <strong>of</strong> functions L 2 ,the space <strong>of</strong> square <strong>in</strong>tegrable measurable real valued functions. Bergstrom (Bergstrom, 1985)considered the space L 2 [a, b] <strong>of</strong> functions def<strong>in</strong>ed on the bounded segment [a, b] ⊂ R, where[a, b] represents the sample space. As he po<strong>in</strong>ts out, there is no need to assume anyth<strong>in</strong>gfurther than cont<strong>in</strong>uity for the unknown function. 7 Every cont<strong>in</strong>uous unknown function onthe segment [a, b] is bounded <strong>and</strong> belongs to the Hilbert space L 2 [a, b].However when the sample space is unbounded, such as R + , the square <strong>in</strong>tegrability condition<strong>of</strong> be<strong>in</strong>g <strong>in</strong> L 2 (R + ) function imposes significantly more restrictions. For example, forcont<strong>in</strong>uous functions <strong>of</strong> bounded variation, it requires that the functions to be estimated havea well def<strong>in</strong>ed limit at <strong>in</strong>f<strong>in</strong>ity, such as lim t→∞ f (t) =0. This is not a reasonable restriction toimpose on the unknown function, for example, if the function represents capital accumulation,which typically <strong>in</strong>creases over time. <strong>The</strong> restriction on lim t→∞ f (t) elim<strong>in</strong>ates also otherst<strong>and</strong>ard cases, such as constant, <strong>in</strong>creas<strong>in</strong>g or cyclical functions.In mathematical terms, an appropriate transformation <strong>of</strong> the l<strong>in</strong>e can alleviate the problem.This was the methodology <strong>in</strong>troduced <strong>in</strong> <strong>Chichilnisky</strong> (1976 <strong>and</strong> 1977), the first publicationsto use Hilbert spaces <strong>in</strong> economics. I def<strong>in</strong>ed then a Hilbert space L 2 (R + ) with a ‘weightfunction’ γ(t) that def<strong>in</strong>es a f<strong>in</strong>ite density measure for R + . 8 In this case, square <strong>in</strong>tegrabilityrequires far less, only that the product <strong>of</strong> the function times the weight function, f (t)γ(t),converges to zero at <strong>in</strong>f<strong>in</strong>ity, rather then the function f (t) itself. This is a more reasonableassumption, which is asymptotically satisfied by the solutions <strong>in</strong> most optimal growth models,where there is well def<strong>in</strong>ed a ‘discount’ factor γ > 1. <strong>The</strong> solution I considered was the(weighted) Hilbert space L 2 (R + , γ) <strong>of</strong> all measurable functions f for which the absolute value<strong>of</strong> the ‘discounted’ product f (t)e −γt is square <strong>in</strong>tegrable, (<strong>Chichilnisky</strong>, 1976 <strong>and</strong> 1977). As


<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong><strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces 5<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong> <strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces7already stated this does not require lim t→∞ f (t) = 0, <strong>and</strong> it <strong>in</strong>cludes bounded, <strong>in</strong>creas<strong>in</strong>g<strong>and</strong> cyclical real valued functions on R + . 9 It is <strong>of</strong> course possible to <strong>in</strong>clude other weightfunctions as part <strong>of</strong> the methodology <strong>in</strong>troduced <strong>in</strong> (<strong>Chichilnisky</strong> 1976, 1977), provided theweight functions are monotonically decreas<strong>in</strong>g <strong>and</strong> therefore <strong>in</strong>vertible, but the ones specified<strong>in</strong> <strong>Chichilnisky</strong> (1976 <strong>and</strong> 1977) are naturally associated with the models at h<strong>and</strong>. This solutionis an improvement, but the condition that the unknown function belongs to a Hilbert spacestill poses asymptotic restrictions at <strong>in</strong>f<strong>in</strong>ity, which are considered below.In the case <strong>of</strong> optimal growth models <strong>Chichilnisky</strong> (1977), the methodology <strong>of</strong> weightedHilbert spaces is based on a transformation map <strong>in</strong>duced by the model itself, its own ‘discountfactor’ γ : R + → [0, 1), γ(t) = e −γt . Under this transformation, the unbounded samplespace R + is mapped <strong>in</strong>to the bounded sample space [0, 1) where the orig<strong>in</strong>al assumptions <strong>and</strong>results for bounded sample spaces can be re-<strong>in</strong>terpreted appropriately <strong>in</strong> a bounded samplespace. This is the route followed <strong>in</strong> this paper.Before do<strong>in</strong>g so, however, it seems worth discuss<strong>in</strong>g briefly a different methodology that hasbeen suggested for <strong>NP</strong> estimation with unbounded sample spaces, 10 expla<strong>in</strong><strong>in</strong>g why it maybe less suitable.5. Compactify<strong>in</strong>g the sample spaceA natural approach to extend <strong>NP</strong> estimation to unbounded sample spaces would be tocompactify the sample space, <strong>and</strong> apply the exist<strong>in</strong>g results to the compactified space. Forexample, the compactification <strong>of</strong> the positive real l<strong>in</strong>e R + yields a space that is equivalent to abounded <strong>in</strong>terval [a, b]. To proceed with <strong>NP</strong> estimation, one needs to re<strong>in</strong>terpret every functionf : R + → R as a function def<strong>in</strong>ed on the compactified space, ˜f : ˜R → R. Asweseebelow,this requires from the onset that the function f on R has a well-def<strong>in</strong>ed limit<strong>in</strong>g behaviorat <strong>in</strong>f<strong>in</strong>ity, namely lim t→∞ f (t) < ∞. Otherwise, f cannot be extended to a function on thecompactified space. To lift this constra<strong>in</strong>t, Peter Phillips suggested that one could estimate(rather than assume) the behavior <strong>of</strong> the unknown function at <strong>in</strong>f<strong>in</strong>ity. 11 But <strong>in</strong> all cases, somelimit must be assumed for the unknown function, which can be considered an unrealisticrequirement. <strong>The</strong> follow<strong>in</strong>g example shows why.Consider the Alex<strong>and</strong>r<strong>of</strong>f one po<strong>in</strong>t compactification <strong>of</strong> the real l<strong>in</strong>e R + , which consists <strong>of</strong> ‘add<strong>in</strong>g’to the real numbers a po<strong>in</strong>t <strong>of</strong> <strong>in</strong>f<strong>in</strong>ity {∞}, <strong>and</strong> def<strong>in</strong><strong>in</strong>g the correspond<strong>in</strong>g neighborhoods<strong>of</strong> <strong>in</strong>f<strong>in</strong>ity. This is a frequently used technique <strong>of</strong> compactification. A function f on the l<strong>in</strong>eR can be extended to a function on the compactified l<strong>in</strong>e but only if f has a well - def<strong>in</strong>edlimit<strong>in</strong>g behavior at <strong>in</strong>f<strong>in</strong>ity, namely if there exists a well def<strong>in</strong>ed lim t→∞ f (t). Thisisnotalways possible nor a reasonable restriction to impose, for example, this requirement excludesall cyclical functions, for which lim t→∞ f (t) does not exist.One can explore more general forms <strong>of</strong> compactification, such as the Stone - Cechcompactification <strong>of</strong> the l<strong>in</strong>e ̂R, the most general possible compactification <strong>of</strong> the real l<strong>in</strong>e. 12 ̂R isa well behaved Hausdorff space, <strong>and</strong> is a universal compactifier <strong>of</strong> R, which means that everyother compactification <strong>of</strong> R is a subset <strong>of</strong> it. Any function f : R → R can be extended to afunction on the compactified space, ̂f : ̂R → R. However it is difficult to <strong>in</strong>terpret HilbertSpaces <strong>of</strong> functions def<strong>in</strong>ed on ̂R, s<strong>in</strong>ce these would be square <strong>in</strong>tegrable functions def<strong>in</strong>ed onultrafilters rather than on real numbers. Such spaces do not have a natural <strong>in</strong>terpretation.To overcome these difficulties, <strong>in</strong> the follow<strong>in</strong>g we use weighted Hilbert Spaces for <strong>NP</strong>estimation on unbounded samples spaces.


8 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications6 Will-be-set-by-IN-TECH6. <strong>NP</strong> estimation on Weighted Hilbert spacesFollow<strong>in</strong>g <strong>Chichilnisky</strong> (1976), (1977) consider the sample space R + =[0, ∞) with a st<strong>and</strong>ardσ field <strong>and</strong> a f<strong>in</strong>ite density or ‘weight function’ γ : R + → [1, 0), γ(t) = e −γt , γ > 1,∫R + e −γt dt < ∞. Def<strong>in</strong>e the weighted Hilbert space H γ , also denoted H, consist<strong>in</strong>g <strong>of</strong> allmeasurable <strong>and</strong> square <strong>in</strong>tegrable functions g(.) : R + → R with the weighted L 2 norm ‖ . ‖∫‖ g ‖ 2 =(R g2 (t)e −γt dt) 1/2+Observe that the space H conta<strong>in</strong>s the space <strong>of</strong> bounded measurable functions L ∞ (R + ),<strong>and</strong><strong>in</strong>cludes all periodic <strong>and</strong> constant functions, as well as many <strong>in</strong>creas<strong>in</strong>g functions.<strong>The</strong> weight function γ <strong>in</strong>duces a homeomorphism, namely a bi-cont<strong>in</strong>uous one to one<strong>and</strong> onto transformation, between the positive real l<strong>in</strong>e <strong>and</strong> the <strong>in</strong>terval [1, 0), γ : R + →[0, 1), γ(t) = e −γt . In the follow<strong>in</strong>g we use a modified homeomorphism δ : R + → [0, 1)def<strong>in</strong>ed as δ(t) = 1 − γ(t) ∈ [0, 1] to ma<strong>in</strong>ta<strong>in</strong> the st<strong>and</strong>ard order <strong>of</strong> the l<strong>in</strong>e. <strong>The</strong>transformation δ allows us to translate Bergstrom’s 1985 methodology, assumptions <strong>and</strong>notation, which are valid for [0, 1], to the positive real l<strong>in</strong>e R + . <strong>The</strong> follow<strong>in</strong>g section <strong>in</strong>terpretsthe statistical assumptions <strong>in</strong> Bergstrom (1985) for <strong>NP</strong> estimation <strong>in</strong> this new context, <strong>and</strong><strong>in</strong>troduces new statistical assumptions.7. Statistical assumptions <strong>and</strong> results on R +We have a sample <strong>of</strong> N paired observations (t 1 , y 1 )..., (t N , y N ) <strong>in</strong> which t 1 , ...t N are nonr<strong>and</strong>om positive real numbers whose values are fixed by the statistician <strong>and</strong> y 1 , ...y N arer<strong>and</strong>om variables whose jo<strong>in</strong>t distribution depends on t 1 , ...t N . we may In particular it isassumed that E(y i ) = f (δ(t i )) = f (x i ), (i = 1, ..., N) where f is an unknown function,δ : R + → [0, 1) is the one to one transformation def<strong>in</strong>ed above, <strong>and</strong> x i = δ(t i ).We are concerned with estimat<strong>in</strong>g an unknown function g : R + → R over the sample spaceR + or, equivalently, estimat<strong>in</strong>g the function f over the bounded <strong>in</strong>terval [0, 1) def<strong>in</strong>ed byf (.) =(g ◦ δ −1 )(.)=g(δ −1 (.)) : [0, 1) → R. <strong>The</strong> model is precisely described by Assumptions1 to 4 below, which are a transformed version <strong>of</strong> the Assumptions <strong>in</strong> Bergstrom (1985), section2, p. 11. We also require a new statistical assumption, Assumption 3 below, which is neededdue to the unbounded nature <strong>of</strong> our sample space 13 .Observe that, given the properties <strong>of</strong> the transformation map δ, it is statistically equivalentto work with the non r<strong>and</strong>om variables t 1 , ...t N or, <strong>in</strong>stead, with the transformed non r<strong>and</strong>omvariables x 1 = x 1 (t 1 )...x N = x N (t N ). To simplify the comparison with Bergstrom’s (1985)results, it seems best to use the latter variables when describ<strong>in</strong>g the statistical model:Assumption 1: (Sampl<strong>in</strong>g assumption) <strong>The</strong> observable r<strong>and</strong>om variables y 1 , ...y N are assumed tobe generated by the equationsy i = f (x i )+u i = f (δ(t i )) + u iwherex i = a + b − a2Nx i+1 = x i + b − a , i = 1, ..., N − 1N


<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong><strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces 7<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong> <strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spacesa, b are constants (1 b > a 0) <strong>and</strong> u 1 ...u N are unobservable r<strong>and</strong>om variables 14 satisfy<strong>in</strong>gthe conditions:E(u i )=0E(u 2 i )=σ2E(u i , u j )=0 i ̸= j, i = 1, ..., N.Assumption 2: <strong>The</strong> unknown function g : R + → R is cont<strong>in</strong>uous or, equivalently, the‘transformed’ function f : [0, 1) → R def<strong>in</strong>ed by f (.) =goδ −1 (.) : [0, 1) → R, is cont<strong>in</strong>uous.When the doma<strong>in</strong> <strong>of</strong> a function f - namely the sample space - is the closed bounded <strong>in</strong>terval[0, 1] then, be<strong>in</strong>g cont<strong>in</strong>uous, f is bounded <strong>and</strong> f ∈ L 2 [0, 1] as po<strong>in</strong>ted out <strong>in</strong> Bergstrom (1985),p. 11. One may therefore apply Hilbert Spaces techniques for <strong>NP</strong> estimation.In our case, the (transformed) function f is def<strong>in</strong>ed over the (half open) <strong>in</strong>terval [0, 1). Underappropriate boundary conditions f can be extended to the closed <strong>in</strong>terval [0, 1]. Cont<strong>in</strong>uityover the closed bounded <strong>in</strong>terval implies boundedness, <strong>and</strong> furthermore it ensures thatf ∈ L 2 [0, 1]. But this is no longer true when the sample space is the positive real l<strong>in</strong>e R + ,or, equivalently, the transformed sample space is δ(R + ) = [0, 1). A cont<strong>in</strong>uous functiondef<strong>in</strong>ed on R + may not be bounded, <strong>and</strong> may not belong to L 2 (R + ). 15 For the unboundedsample space R + , we require the follow<strong>in</strong>g additional statistical assumption on the unknownfunction:Assumption 3: <strong>The</strong> unknown function g : R + → R is <strong>in</strong> the Hilbert Space H or, equivalently, thetransformed function f : [0, 1) → R can be extended to a cont<strong>in</strong>uous function f : [0, 1] → R.Assumption 4: <strong>The</strong> countable set <strong>of</strong> cont<strong>in</strong>uous functions φ 1(x(t)), ..., φ N(x(t)) is a completeorthonormal set <strong>in</strong> the space L 2 (R + ) <strong>of</strong> square <strong>in</strong>tegrable functions on R + with ord<strong>in</strong>aryLebesgue measure μ.This requires that the functions φ j be cont<strong>in</strong>uous, l<strong>in</strong>early <strong>in</strong>dependent, dense <strong>in</strong> L 2 (R + ) <strong>and</strong>satisfy the conditions∫ 1φ 2 j (x)dx = 1, (j = 1, 2, ...)0<strong>and</strong> ∫ 1φ j (x).φ i (x)dx = 0, (j ̸= i; j, i = 1, 2...).0Observe that one can consider different orthonormal sets, for example, (Bergstrom, 1985)considers an orthonormal set consist<strong>in</strong>g <strong>of</strong> polynomials on <strong>in</strong>creas<strong>in</strong>g order.On the basis <strong>of</strong> these Assumptions (1, 2, 3 <strong>and</strong> 4) the follow<strong>in</strong>g results, which are reproducedfrom Bergstrom, 1985, obta<strong>in</strong> directly from those <strong>of</strong> Bergstrom, 1985. <strong>The</strong>se results areexpressed <strong>in</strong> the transformed unknown function f : [0, 1] → R to facilitate comparison withBergstrom (1985) but can be equivalently expressed on the unknown function g : R + → R :<strong>The</strong>orem 1. (Bergstrom, 1985) Let ∧ f MN(x) be def<strong>in</strong>ed bywhereare the values <strong>of</strong>∧f MN (x) = ∧ c 1 (M, N)φ 1 (x)+... + ∧ c M (M, N)φ M (x) (1)∧c1 (M, N)φ 1 (x), ..., ∧ c M (M, N)φ M(x)c 1 , c 2 , ..., c M9


10 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications8 Will-be-set-by-IN-TECHthat m<strong>in</strong>imizeN∑{y 1 − c 1 φ 1(x) − ... − c M φ M(x)} 2i=1i.e. there are sample regression coefficients. <strong>The</strong>n for an arbitrarily small real number ε > 0, there areM ε <strong>and</strong> N ε (M) such that∫ bif M > M ε <strong>and</strong> N > N ε (M).E[a∧f MN (x) − f (x)dx] < ε<strong>The</strong>orem 2. (Bergstrom, 1985) Let M ∗ be the smallest <strong>in</strong>teger such that[ ∫ 1] [ ∫E { ̂f1]M ∗ N(x) − f (x)} 2 ≤ E { ̂f MN (x) − f (x)} 2 (M = 1, ..., N)00where ̂f MN (x) is def<strong>in</strong>ed by (1) <strong>and</strong> let fN ∗ (x) be def<strong>in</strong>ed byf ∗ N (x) = ̂f M ∗ N(x).<strong>The</strong>n under Assumptions 1-4,[ ∫ 1]lim { fN ∗ (x) − f N→∞(x)}2 dx = 0.0Def<strong>in</strong>ition 3. Let c 1 , ..., c n , ... be the Fourier coefficients <strong>of</strong> f (x) relative to the orthonormal setφ 1 , ..., φ n <strong>in</strong> the transformed set [0, 1],namely∫ 1c j =0f (x)φ j (x)dx, (j = 1, 2, ...).Observe that under the conditions the set φ 1 , ..., φ n is orthonormal <strong>and</strong> therefore complete <strong>in</strong>L 2 [0, 1] so that∫ 1Mlim { f (x) − ∑ c j φ j (x)} 2 = 0,M→∞ 0j=1<strong>and</strong> Parseval’s <strong>in</strong>equality is satisfied (Kolmogorov, 1961, p. 98)∫ 1f 2 ∞(x)dx = ∑ c 2 j .0j=1<strong>The</strong>orem 4. (Bergstrom 1985) Under Assumptions 1-4,M ∗∑ c 2 j ≥j=M+1M∑ c 2 j j=M ∗ +1M ∗∑j=1M∑j=1E(ĉ j (M ∗ , N) − c j ) 2 −M∑j=1E(ĉ j (M, N) − c j ) 2 (M = 1, ..., M ∗ − 1)E(ĉ j (M, N) − c j ) 2 M ∗− ∑ E(ĉ j (M ∗ , N) − c j ) 2 (M = M ∗ + 1, ..., N)j=1


<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong><strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces 9<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong> <strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces11From the def<strong>in</strong>ition <strong>of</strong> the transformation δ <strong>and</strong> Assumptions 1 to 4, the pro<strong>of</strong>s for thetheorems above follow directly from <strong>The</strong>orems 1, 2 <strong>and</strong> 3 <strong>in</strong> Bergstrom 1985..<strong>The</strong>orems 1, 2 <strong>and</strong> 4 are quite general, but the underly<strong>in</strong>g assumptions (1 to 4) still require<strong>in</strong>terpretation for the case <strong>of</strong> unbounded sample spaces. <strong>The</strong> follow<strong>in</strong>g section tackles thisissue.8. Statistical assumptions on R +Assumptions 1, 2 <strong>and</strong> 4 have a ready <strong>in</strong>terpretation <strong>in</strong> the transformed sample space.Assumption 3 is however <strong>of</strong> a different nature. It requires that the unknown functiong : R + → R be an element <strong>of</strong> a (weighted) Hilbert space or, equivalently, that the transformedunknown function f : [0, 1) → R can be extended to a cont<strong>in</strong>uous function <strong>in</strong> the Hilbert spaceL 2 [0, 1]. This condition is critical: when Assumption 3 is satisfied <strong>The</strong>orems 1, 2 <strong>and</strong> 4 extend<strong>NP</strong> estimation to R + , but otherwise these theorems, which depend on the properties <strong>of</strong> L 2functions <strong>and</strong> the convergence <strong>of</strong> their Fourier coefficients, no longer work. What conditionsare needed to ensure that Assumption 3 holds? 16 <strong>The</strong> follow<strong>in</strong>g provides classical statisticalconditions <strong>in</strong>volv<strong>in</strong>g relative likelihoods (cf. De Groot, 2004, Chapter 6).<strong>The</strong>orem 5. If a relative likelihood ≼ satisfies assumptions SP 1 to SP 5 <strong>of</strong> De Groot (2004) Chapter 6,then there exists a probability function f : R + → R represent<strong>in</strong>g the relative likelihood ≼ where f isan element <strong>of</strong> the Hilbert space L 2 (R + ) <strong>and</strong> Assumption 3 above is satisfied.Pro<strong>of</strong>: Consider the five assumptions SP 1 , ..., SP 5 provided <strong>in</strong> Degroot (2004) Chapter 6.Together they imply the existence <strong>of</strong> a countably additive probability measure on R + thatagrees with the relative likelihood order (cf. Degroot, 2004), Section 6.4, p. 76-77). Givenany countably additive measure μ on R one can always f<strong>in</strong>d a functional representationas a measurable function, f : R + → R, thatis<strong>in</strong>tegrable, f ∈ L 1 (R + ) <strong>and</strong> satisfy<strong>in</strong>gμ(A) = ∫ A f (x)dx (Yosida 1952). In other words, the five assumptions SP 1, ..., SP 5 guaranteethe existence <strong>of</strong> an absolutely cont<strong>in</strong>uous distribution represent<strong>in</strong>g the ‘relative likelihood <strong>of</strong>events’ (Degroot, 2004).S<strong>in</strong>ce the space <strong>of</strong> <strong>in</strong>tegrable functions on the (positive) real l<strong>in</strong>e is conta<strong>in</strong>ed <strong>in</strong> the space<strong>of</strong> square <strong>in</strong>tegrable functions on the (positive) real l<strong>in</strong>e, L 1 (R + ) ⊂ L 2 (R + ) (Yosida, 1952)it follows, under the assumptions, that f ∈ L 2 (R + ) as we wished to prove. Thus the fivestatistical assumptions <strong>of</strong> Degroot (2004) suffice to guarantee our Assumption 3, <strong>and</strong> hencetheresults<strong>of</strong><strong>The</strong>orems1,2<strong>and</strong>4.Among the five fundamental statistical assumptions <strong>of</strong> Degroot (2004) there is one, SP 4 ,whichplays a key role: it is necessary <strong>and</strong> sufficient to extend the <strong>NP</strong> estimation results to unknowndensity functions on R + .<strong>The</strong> next step is to def<strong>in</strong>e assumption SP 4 <strong>and</strong> expla<strong>in</strong> its role. <strong>The</strong>notation A ≽ B <strong>in</strong>dicates that the likelihood <strong>of</strong> the set or event A is higher than the likelihood<strong>of</strong> B, see Degroot (2004).Def<strong>in</strong>ition 6. Assumption SP 4 (De Groot 2004): Let A 1 ⊃ A 2 ⊃ ...be a decreas<strong>in</strong>g sequence <strong>of</strong>events, <strong>and</strong> B some fixed event such that A i B for i = 1, 2...., <strong>The</strong>n ⋂ ∞i=1 A i B i .To clarify the role <strong>of</strong> SP 4 , suppose that each <strong>in</strong>f<strong>in</strong>ite <strong>in</strong>terval <strong>of</strong> the form (n, ∞) ⊂ R, n = 1, 2, ...is regarded as more likely (by the relative likelihood) than some fixed small subset B <strong>of</strong> R.S<strong>in</strong>ce the <strong>in</strong>tersection <strong>of</strong> all these <strong>in</strong>tervals is empty, B must be equivalent to the empty set φ.In other words, if B is more likely than the empty set, B ≻ φ, then regardless <strong>of</strong> how small is


12 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications10 Will-be-set-by-IN-TECHB is, it is impossible for every <strong>in</strong>f<strong>in</strong>ite <strong>in</strong>terval (n, ∞) to be as likely as B. One way to <strong>in</strong>terpretthe role <strong>of</strong> Assumption SP 4 is <strong>in</strong> avert<strong>in</strong>g ‘heavy tails’:Def<strong>in</strong>ition 7. We say that a relative likelihood has ‘heavy tails’ when for any given set B, there existan N > 0 such that n > N<strong>and</strong>C⊃ (n, ∞), C B namely C is as likely as B ⊂ R + . 17Intuitively, this def<strong>in</strong>ition states that there exist <strong>in</strong>f<strong>in</strong>ite <strong>in</strong>tervals or ‘tail sets’ <strong>of</strong> the form (n, ∞)with arbitrarily large measure, which may be <strong>in</strong>terpreted as ‘heavy tails’.<strong>The</strong>orem 8. When assumption SP 4 fails, relative likelihoods have ‘heavy tails’.Pro<strong>of</strong>: <strong>The</strong> logical negation <strong>of</strong> SP 4 implies that there exists a large enough n such that (n, ∞) isas likely than B, for any bounded B. This implies that the probability measure <strong>of</strong> the event(n, ∞) doesnotgotozerowhenn goes to <strong>in</strong>f<strong>in</strong>ity. <strong>The</strong>refore, one obta<strong>in</strong>s ‘heavy tails’ asdef<strong>in</strong>ed above.It is possible to <strong>in</strong>terpret SP 4 to apply to any unknown function f : R + → R with<strong>in</strong> thestatistical model def<strong>in</strong>ed above. For this one must re<strong>in</strong>terpret the relationship ≼ that appears<strong>in</strong> the def<strong>in</strong>ition <strong>of</strong> SP 4 as follows:Def<strong>in</strong>ition 9. Let f : R + → R be a cont<strong>in</strong>uous positive valued function. <strong>The</strong>n the expressionA ≼ Bmeans ∫ A fdx < ∫ B fdx,where <strong>in</strong>tegration is with respect to the st<strong>and</strong>ard measure onR + . 1When work<strong>in</strong>g <strong>in</strong> Hilbert spaces, we use a similar def<strong>in</strong>ition <strong>of</strong> the expression ≼ to obta<strong>in</strong>necessary <strong>and</strong> sufficient conditions below:Def<strong>in</strong>ition ∫ 10. Let f : R + → R be a cont<strong>in</strong>uous function. <strong>The</strong>n the expression A ≼ BmeansA f 2 dx < ∫ B f 2 dx, where <strong>in</strong>tegration is with respect to the st<strong>and</strong>ard measure on R + . 18<strong>The</strong> follow<strong>in</strong>g extends SP 4 to any cont<strong>in</strong>uous function f : R + → R:Def<strong>in</strong>ition 11. Assumption SP 4 <strong>in</strong> Hilbert spaces. Let A 1 ⊃ A 2 ⊃ ...be a decreas<strong>in</strong>g sequence<strong>of</strong> sets <strong>in</strong> R + ,<strong>and</strong>B some fixed set such that A i B, namely ∫ A if 2 (x)dx > ∫ B f 2 (x)dx fori = 1, 2....,then ⋂ ∞i=1 A i B i .In other words, if B is any set such that ∫ B f 2 (x)dx > 0, then regardless <strong>of</strong> how small is B, itis impossible for every <strong>in</strong>f<strong>in</strong>ite <strong>in</strong>terval (n, ∞) to satisfy ∫ (n,∞) f 2 (x)dx > ∫ B f 2 (x)dx. Thisisareasonable extension <strong>of</strong> SP 4 provided above.9. SP4 is necessary <strong>and</strong> sufficient for extend<strong>in</strong>g <strong>NP</strong> estimation to R +To obta<strong>in</strong> specific necessary <strong>and</strong> sufficient conditions for <strong>NP</strong> estimation, consider now thestatistical model def<strong>in</strong>ed above, <strong>and</strong> assume that all the statistical assumptions <strong>of</strong> Bergstrom(1985) are satisfied, namely Assumptions 1, 2 <strong>and</strong> 4. We study the estimation <strong>of</strong> an unknownfunction g : R + → R. When the model is restricted to the bounded sample space [0, 1],namely g : [0, 1] → R, <strong>The</strong>orems 1, 2 <strong>and</strong> 4 <strong>of</strong> Bergstrom (1985) ensure the existence <strong>of</strong> an <strong>NP</strong>estimator <strong>in</strong> Hilbert spaces with the appropriate asymptotic behavior. <strong>The</strong> follow<strong>in</strong>g providesa necessary <strong>and</strong> sufficient condition for extend<strong>in</strong>g the <strong>NP</strong> estimation results from the samplespace [0, 1] to the unbounded sample space R + :1 Observe that this <strong>in</strong>terpretation <strong>of</strong> the relationship ≼ is identical the def<strong>in</strong>ition <strong>of</strong> relative likelihoodwhen f is a density function. <strong>The</strong>refore it agrees with the def<strong>in</strong>ition provided <strong>in</strong> the previous section.


<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong><strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces 11<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong> <strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces13<strong>The</strong>orem 12. Assumption SP 4 <strong>of</strong> De Groot (2004), as extended above, is necessary <strong>and</strong> sufficient forextend<strong>in</strong>g <strong>NP</strong> estimation <strong>in</strong> Hilbert Spaces from the sample space [0,1] to the unbounded sample spaceR + .Pro<strong>of</strong>: This follows directly from <strong>The</strong>orems 1, 2, 4, 5 <strong>and</strong> 8 above. Observe that when SP 4 fails, the distribution <strong>in</strong>duced by the density f is not countablyadditive <strong>and</strong> cannot be represented by a function <strong>in</strong> H, <strong>and</strong> the estimator, which is constructedfrom Fourier coefficients, fails to converge.10. Connection with decision theory<strong>The</strong> general applicability <strong>of</strong> <strong>NP</strong> estimation, <strong>and</strong> the central role played by assumption SP 4 ,make it desirable to situate the results <strong>in</strong> the context <strong>of</strong> the larger literature. A naturalconnection that comes to m<strong>in</strong>d is decision theory. <strong>The</strong>re is an logical parallel between theclassic assumptions on relative likelihood (De Groot, 2004) <strong>and</strong> the classic axioms <strong>of</strong> decisionmak<strong>in</strong>g under uncerta<strong>in</strong>ty (Arrow, 1970). From assumptions on relative likelihood one obta<strong>in</strong>sprobability measures that represent the likelihood <strong>of</strong> events. From the axioms <strong>of</strong> decisionmak<strong>in</strong>g under uncerta<strong>in</strong>ty, one derives subjective probability measures that def<strong>in</strong>e expectedutility. One would expect to f<strong>in</strong>d an axiom <strong>in</strong> the foundations <strong>of</strong> choice under uncerta<strong>in</strong>tythat corresponds to assumption SP 4 on relative utility. Such an axiom exists: it is calledMonotone Cont<strong>in</strong>uity <strong>in</strong> Arrow (1970) <strong>and</strong> as shown below, it is equivalent to SP 4 .Weusest<strong>and</strong>ard def<strong>in</strong>itions for actions <strong>and</strong> lotteries used <strong>in</strong> the theory <strong>of</strong> choice under uncerta<strong>in</strong>ty, seee.g. Arrow (1970) <strong>and</strong> <strong>Chichilnisky</strong> (2000).Def<strong>in</strong>ition 13. A vanish<strong>in</strong>g sequence <strong>of</strong> sets <strong>in</strong> the real l<strong>in</strong>e R is a family <strong>of</strong> <strong>of</strong> sets {A i } i=1,.... ⊂ R +satisfy<strong>in</strong>g A 1 ⊃ A 2 ⊃ ... ⊃ A i ...,<strong>and</strong> ⋂ ∞i=1 A i = φ.Def<strong>in</strong>ition 14. <strong>The</strong> expression A ≻ B is used to <strong>in</strong>dicate that action A ⊂ R is ‘preferred’ to actionB ⊂ R.Def<strong>in</strong>ition 15. Monotone Cont<strong>in</strong>uity Axiom (MCA, Arrow (1970)) Given two actions A <strong>and</strong> B whereA ≻ B <strong>and</strong> a vanish<strong>in</strong>g sequence {E i }, suppose that {A i } <strong>and</strong> {B i } yield the same consequences as A<strong>and</strong> B on E c i <strong>and</strong> any arbitrary consequence c on E i . <strong>The</strong>n for all i sufficiently large, A i ≻ B i .<strong>The</strong> follow<strong>in</strong>g results use the identification see Yosida (1952, 1974), , <strong>Chichilnisky</strong> (2000) <strong>of</strong> adistribution on the l<strong>in</strong>e R with a cont<strong>in</strong>uous l<strong>in</strong>ear real valued function def<strong>in</strong>ed on the space<strong>of</strong> bounded functions on the l<strong>in</strong>e, L ∞ (R). 19<strong>The</strong>orem 16. Assumption SP 4 <strong>of</strong> De Groot (2004) is equivalent to the Monotone Cont<strong>in</strong>uity Axiom(1970).Pro<strong>of</strong>: <strong>The</strong> strategy is to show that SP 4 <strong>and</strong> the Monotone Cont<strong>in</strong>uity Axiom (MCA)areeachnecessary <strong>and</strong> sufficient for the existence <strong>of</strong> a rank<strong>in</strong>g <strong>of</strong> events ≼ <strong>in</strong> R + (by relative likelihood,or by choice, respectively) that is representable by an <strong>in</strong>tegrable function on R + . 20 Considerfirst the Monotone Cont<strong>in</strong>uity Axiom (MCA). <strong>Chichilnisky</strong> (2006) showed it is necessary<strong>and</strong> sufficient for the existence <strong>of</strong> a choice function that is a cont<strong>in</strong>uous l<strong>in</strong>ear function onR, anelement<strong>of</strong>thedualspaceL ∗ ∞(R), represented by a countably additive measure on R<strong>and</strong> thus admitt<strong>in</strong>g a representation by an <strong>in</strong>tegrable function <strong>in</strong> L 1 (R). <strong>The</strong> argument is asfollows: the dual space L ∗ ∞(R) is (by def<strong>in</strong>ition) the space <strong>of</strong> all cont<strong>in</strong>uous l<strong>in</strong>ear real valuedfunctions on L ∞ (R + ). It has been shown that this space consists (Yosida, 1952, 1974) <strong>of</strong> both


14 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications12 Will-be-set-by-IN-TECHcountably additive <strong>and</strong> purely f<strong>in</strong>itely additive measures on R. <strong>Chichilnisky</strong> (2006) showedMonotone Cont<strong>in</strong>uity Axiom rules out purely f<strong>in</strong>itely additive l<strong>in</strong>ear measures <strong>and</strong> ensuresthat the choice criterion is represented by a countably additive measure on R, <strong>The</strong>orem2<strong>of</strong> <strong>Chichilnisky</strong> (2006). S<strong>in</strong>ce a countably additive measure on R can always be representedby an <strong>in</strong>tegrable function <strong>in</strong> L 1 (R + ) (Yosida, 1952, 1974), this completes the first part <strong>of</strong> thepro<strong>of</strong>. Consider now SP 4 . De Groot De Groot (2004) showed that Assumption SP 4 elim<strong>in</strong>atesdistributions that are purely f<strong>in</strong>itely additive, as shown <strong>in</strong> para. 3, page 73 Section 6.2 <strong>of</strong> DeGroot (2004), ensur<strong>in</strong>g that the distribution is represented by a countably additive measure,which completes the pro<strong>of</strong>.11. Rare events <strong>and</strong> susta<strong>in</strong>abilityWhen estimat<strong>in</strong>g an unknown path f over time, SP 4 can be <strong>in</strong>terpreted as a condition on thebehavior <strong>of</strong> the unknown function on f<strong>in</strong>ite <strong>and</strong> <strong>in</strong>f<strong>in</strong>ite time <strong>in</strong>tervals. A related necessary<strong>and</strong> sufficient condition has been used <strong>in</strong> the literature on Susta<strong>in</strong>able Development: it iscalled Dictatorship <strong>of</strong> the Present, <strong>Chichilnisky</strong> (1996). For any order ≼ <strong>of</strong> cont<strong>in</strong>uous boundedpaths f : R + → R :Def<strong>in</strong>ition 17. We say that ≼ is a Dictatorship <strong>of</strong> the Present when for any two f <strong>and</strong> g there existsan N = N( f , g) such that f ≼ g ⇔ f ′ ≼ g ′ , for any f ′ <strong>and</strong> g ′ that are identical to f <strong>and</strong> g on the<strong>in</strong>terval [0, N).<strong>The</strong> condition <strong>of</strong> dictatorship <strong>of</strong> the present <strong>Chichilnisky</strong> (1996) is equivalent to therepresentation <strong>of</strong> a welfare criterion by countably additive measures, <strong>and</strong> by an attendant<strong>in</strong>tegrable function on the l<strong>in</strong>e. <strong>The</strong> condition is also logically identical to Insensitivity toRare Events <strong>Chichilnisky</strong> (2000, 2006), when the numbers <strong>in</strong> the real l<strong>in</strong>e R + represents eventsrather than time periods:Def<strong>in</strong>ition 18. (<strong>Chichilnisky</strong> (2000, 2006)) A rank<strong>in</strong>g <strong>of</strong> lotteries W : L → R is called Insensitiveto Rare Events when for any two lotteries, f <strong>and</strong> g, thereisanε > 0, ε = ε( f , g) such that W( f ) >W(g) ⇔ W( f ′ ) > W(g ′ ) for every f ′ <strong>and</strong> g ′ that differ from f <strong>and</strong> g solely on sets <strong>of</strong> measure smallerthan ε.Def<strong>in</strong>ition 19. (<strong>Chichilnisky</strong> 2000, 2006) A rank<strong>in</strong>g <strong>of</strong> lotteries W : L → R is Sensitive to RareEvents when it is not Insensitive to Rare Events.<strong>The</strong>orem 20. Assumption SP 4 is equivalent to Monotone Cont<strong>in</strong>uity <strong>and</strong> to Insensitivity for RareEvents, <strong>and</strong> the latter is logically identical to Dictatorship <strong>of</strong> the Present. In their appropriate contexts,each <strong>of</strong> the four conditions (SP 4 , Monotone Cont<strong>in</strong>uity, Insensitivity for Rare Events, <strong>and</strong> Dictatorship<strong>of</strong> the Present) is necessary <strong>and</strong> sufficient for extend<strong>in</strong>g <strong>NP</strong> estimation results to R + .Pro<strong>of</strong>: <strong>Chichilnisky</strong> (2006) established that Insensitivity to Rare Events is equivalent to theMonotone Cont<strong>in</strong>uity Axiom (MCA) <strong>in</strong> Arrow (1970), cf. <strong>The</strong>orem 2 <strong>in</strong> <strong>Chichilnisky</strong> (2006).<strong>Chichilnisky</strong> (1996, 2000) showed that Insensitivity to Rare Events is logically identical toDictatorship <strong>of</strong> the Present. <strong>The</strong>orems 12 <strong>and</strong> 16 complete the pro<strong>of</strong> <strong>of</strong> the theorem.12. K. Godel <strong>and</strong> the limits <strong>of</strong> mathematics<strong>The</strong> critical condition that allows extend<strong>in</strong>g econometric estimation from bounded doma<strong>in</strong>sto the entire l<strong>in</strong>e is the logical negation <strong>of</strong> purely f<strong>in</strong>itely additive measures, as was shown


<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong><strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces 13<strong>The</strong> <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong> <strong>and</strong> <strong>NP</strong> <strong>Estimation</strong> <strong>in</strong> Hilbert Spaces15<strong>in</strong> the previous Section. <strong>The</strong> constructibility <strong>of</strong> purely f<strong>in</strong>ite measures has been shown <strong>in</strong>turn to be equivalent to the existence <strong>of</strong> "ultrafilters", to Hahn Banach’s theorem <strong>and</strong> theAxiom <strong>of</strong> Choice <strong>in</strong> <strong>Mathematics</strong>, <strong>Chichilnisky</strong> (2009, 2010a, 2010b). Furthermore, the Axiom<strong>of</strong> Choice was established by K. Godel early on to be <strong>in</strong>dependent from the other axioms<strong>of</strong> <strong>Mathematics</strong> (Godel (1943)), so there is a formulation <strong>of</strong> <strong>Mathematics</strong> with the Axiom <strong>of</strong>Choice <strong>and</strong> another without it, both are equally valid. This Axiom <strong>of</strong> Choice itself is thereforean unprovable proposition from the other axioms <strong>of</strong> <strong>Mathematics</strong> - thus provid<strong>in</strong>g a l<strong>in</strong>k withthe ambiguity feature <strong>of</strong> large logical systems that was first identified by K. Godel last century(1943). Equally the two separate <strong>and</strong> dist<strong>in</strong>ct mathematical systems - one with <strong>and</strong> the otherwithout the Axiom <strong>of</strong> Choice – are equally valid <strong>and</strong> they are contradictory with each other.<strong>The</strong>refore there exist mathematically <strong>and</strong> logically correct statements that are contradictorywith<strong>in</strong> the classic body <strong>of</strong> <strong>Mathematics</strong>. <strong>The</strong>se statements confirm K. Godel’s <strong>in</strong>completenesstheorem for <strong>Mathematics</strong>.More precisely, the formal equivalence we are seek<strong>in</strong>g between the results <strong>of</strong> this chapter<strong>and</strong> the <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong>, has been established <strong>in</strong> the previous Section <strong>of</strong> this chapter,where a l<strong>in</strong>k was established to <strong>Chichilnisky</strong>’s axiom <strong>of</strong> "Sensitivity to Rare Events" - which,<strong>in</strong> <strong>Chichilnisky</strong> (2009, 2010a, 2010b, 2011), was proven to be identical with the negation <strong>of</strong> theAxiom <strong>of</strong> Choice.<strong>The</strong> literature on the <strong>Limits</strong> <strong>of</strong> <strong>Mathematics</strong> that was <strong>in</strong>itiated by Godel, is deeply connectedtherefore with the results on the <strong>Limits</strong> <strong>of</strong> Econometrics presented <strong>in</strong> this chapter.13. ConclusionsWe extended Bergstrom’s 1985 results on <strong>NP</strong> estimation <strong>in</strong> Hilbert spaces to unboundedsample sets, us<strong>in</strong>g previous results <strong>in</strong> <strong>Chichilnisky</strong> (1976 <strong>and</strong> 1977). <strong>The</strong> focus was on thestatistical assumptions needed for the extension. When estimat<strong>in</strong>g an unknown function onthe positive l<strong>in</strong>e R + , we obta<strong>in</strong>ed a necessary <strong>and</strong> sufficient condition that derives from aclassic assumption on relative likelihoods, SP 4 <strong>in</strong> De Groot (2004).We extended assumptionSP 4 , <strong>and</strong> therefore the results, to any unknown cont<strong>in</strong>uous function f : R + → R. Wealso showed that the SP 4 assumption is equivalent to well known axioms for choice underuncerta<strong>in</strong>ty, such as the Monotone Cont<strong>in</strong>uity Axiom <strong>in</strong> Arrow (1970), Insensitivity to Rare Events<strong>in</strong> <strong>Chichilnisky</strong> (2000, 2006), <strong>and</strong> to criteria used for susta<strong>in</strong>able choice over time, such asDictatorship <strong>of</strong> the Present (1996).When the key assumptions fail, the estimators on bounded sample spaces that are based onFourier coefficients, do not converge. We showed that this <strong>in</strong>volves ‘heavy tails’ <strong>and</strong> purelyf<strong>in</strong>itely additive measures, thus suggest<strong>in</strong>g a limit to <strong>NP</strong> econometrics.14. Footnotes1. In 1980 Rex Bergstrom <strong>and</strong> I discussed Hilbert spaces at a Colchester pub at a time he <strong>of</strong>feredme the Keynes Chair <strong>of</strong> Economics at the University <strong>of</strong> Essex, which I accepted. Bergstromwas <strong>in</strong>terested <strong>in</strong> my recent work <strong>in</strong>troduc<strong>in</strong>g Hilbert <strong>and</strong> Sobolev Spaces <strong>in</strong> Economics(<strong>Chichilnisky</strong>, 1976, 1977) <strong>and</strong> I suggested that Hilbert Spaces were a natural space to use<strong>in</strong> <strong>NP</strong> Econometrics, which apparently <strong>in</strong>spired his 1985 chapter. Bergstrom passed away <strong>in</strong>2006, <strong>and</strong> his former student Peter Phillips organized this conference <strong>in</strong> his honor. This paperis <strong>in</strong> honor <strong>of</strong> a great man, <strong>and</strong> attempts to complete a conversation between us that was leftpend<strong>in</strong>g for 27 years.


16 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications14 Will-be-set-by-IN-TECH2. In a weighted Hilbert space the real l<strong>in</strong>e R is endowed with a f<strong>in</strong>ite density function, such ase −t , rather than the st<strong>and</strong>ard uniform measure on R.3. See p. 73, Section 6.2 <strong>of</strong> De Groot (2004), para. 4 follow<strong>in</strong>g Assumption SP 4 .4. <strong>NP</strong> estimation <strong>in</strong> Hilbert Spaces was very <strong>in</strong>terest<strong>in</strong>g to me at the time, as I had <strong>in</strong>troducedHilbert spaces <strong>in</strong> economic models <strong>in</strong> a PhD dissertation with Gerard Debreu at UC Berkeley(<strong>Chichilnisky</strong> 1976) <strong>and</strong> <strong>in</strong> a neoclassical optimal growth model (<strong>Chichilnisky</strong> 1977), <strong>in</strong>clud<strong>in</strong>gL 2 ,weightedL 2 <strong>and</strong> Sobolev spaces. A few years later, <strong>in</strong> 1981, Gallant (1981) used aga<strong>in</strong>Sobolev norms for non - parametric estimation.5. <strong>The</strong> same problem arises when the sample space is bounded but not closed, such as [a, b).6. This implies that the estimator f is <strong>in</strong> the Hilbert Space L 2 <strong>of</strong> square <strong>in</strong>tegrable functionsdenoted L 2 [a, b], which is the space <strong>of</strong> measurable functions f : [a, b] → R satisfy<strong>in</strong>g ∫ baf (x) 2 dx < ∞.7. Bergstrom (1985) required the function to be cont<strong>in</strong>uous a.e. on[a, b] which is essentiallythe same <strong>in</strong> our case.8. <strong>The</strong> weighted Hilbert space H is def<strong>in</strong>ed as the space <strong>of</strong> all square <strong>in</strong>tegrable functions onthe positive l<strong>in</strong>e us<strong>in</strong>g the (f<strong>in</strong>ite) density function δ −x :afunction f ∈ H when the ’weighted’<strong>in</strong>tegral ∫ R| + f (x)δ −x | 2 dx < ∞.9. This weaker assumption always works, but has no natural <strong>in</strong>terpretation when the modellacks a ‘discount factor’.10. Private communication with Peter Phillips.11. Private communication.12. This can be described as the space <strong>of</strong> all ultrafilters <strong>of</strong> the real l<strong>in</strong>e R.13. And the fact that [0,1) is not compact.14. To simplify notation we may assume <strong>in</strong> the follow<strong>in</strong>g without loss <strong>of</strong> generality a = 0,b = 1.15. Appropriate boundary conditions are needed for this to be the case, for example, <strong>in</strong> thecase <strong>of</strong> cont<strong>in</strong>uous functions <strong>of</strong> bounded variation,lim x→∞ f (x) =0.16. S<strong>in</strong>ce we consider weight functions γ one could <strong>in</strong>terpret the requirement simply asthe fact that g 2 does not go to <strong>in</strong>f<strong>in</strong>ity "too fast". But what does "too fast" mean <strong>in</strong> a nonparametric context? Compared to what? Impos<strong>in</strong>g a limit<strong>in</strong>g condition at <strong>in</strong>f<strong>in</strong>ity or at aboundary (x → 1) becomes a parametric requirement that conflicts with the <strong>in</strong>tention <strong>of</strong>non-parametric estimation.Alternatively one could choose another "weight<strong>in</strong>g" function ̂γon the def<strong>in</strong>ition <strong>of</strong> H γ for which g ∈ H γ , but this becomes an arbitrary parameter <strong>and</strong>defeats the "non parametric" nature <strong>of</strong> the problem. When estimat<strong>in</strong>g a density functionf over R + one may answer the question by reference to the properties <strong>of</strong> the associatedrelative likelihood function (? ), or, when estimat<strong>in</strong>g an <strong>in</strong>vestment path over time, one mayconsider the behavior <strong>of</strong> the associated capital accumulation path. A referee po<strong>in</strong>ted out thatan alternative choice <strong>of</strong> weight<strong>in</strong>g function is the density <strong>of</strong> the regressor (assum<strong>in</strong>g it hasone). In practice this is not known but could be estimated. If one uses the empirical cdf,̂Π(t) =∑ iI{t i t}/N, thenx i = ̂Π −1 (t i )=(i − 1)/N. ̂Π is not <strong>in</strong>vertible <strong>in</strong> a strict sense,but this can be h<strong>and</strong>led us<strong>in</strong>g a kernel-smoothed ∫version <strong>of</strong> it. Us<strong>in</strong>g the density π(t) =Π ′ (t),the central condition becomes g 2 (x)π(t)dt = E{g 2 (t)} < ∞ <strong>and</strong> highlights that theR +condition concerns both the regression function <strong>and</strong> the distribution / transformation <strong>of</strong> ther<strong>and</strong>om valiable t.


18 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications16 Will-be-set-by-IN-TECH[16] De Groot, M. Optimal Statistical Decisions, John Wiley <strong>and</strong> Sons, Wiley Classics Library,Hoboken, New Jersey, 2004[17] Gallant, A.R. “On the bias <strong>of</strong> flexible functional forms" J. <strong>of</strong> Econometrics, 15, 1981, p.211-246.[18] Newey, W.K. "Convergence Rates <strong>and</strong> Asymptotic Normality for Series Estimators"Journal <strong>of</strong> Econometrics, 79, 147-168, 1997.[19] Kolmogorov, A.N. <strong>and</strong> Fom<strong>in</strong>, S.V. 1961, Elements <strong>of</strong> the theory <strong>of</strong> Functions <strong>and</strong> FunctionalAnalysis, 2, New York: Graylock Press.[20] Priestley M.B. <strong>and</strong> Chao M.T: "Non parametric Function Fitt<strong>in</strong>g", J. Royal Stat. Society,1972.[21] St<strong>in</strong>chcombe, M. “Some Genericity Analysis <strong>in</strong> Nonparametric Statistics", Work<strong>in</strong>gPaper, December 10, 2002.[22] Yosida, K. Funcional Analysis 1974 4th edition, New York Heidelberg: Spr<strong>in</strong>ger Verlag[23] Yosida, K. <strong>and</strong> E. Hewitt, 1952 “F<strong>in</strong>itely Level Independent Measures", Transactions <strong>of</strong> theAmerican Math. Society, 72, 46-66.


Instrument Generat<strong>in</strong>g Function<strong>and</strong> Analysis <strong>of</strong> Persistent Economic Times Series: <strong>The</strong>ory <strong>and</strong> Application 21apply<strong>in</strong>g the nonl<strong>in</strong>ear <strong>in</strong>struments generat<strong>in</strong>g function (IGF thereafter) method, proposedby Phillips et al. (2004), to measure the estimates <strong>of</strong> the half-life <strong>of</strong> shocks to the series. LikeAMU, the IGF estimator <strong>of</strong> Phillips et al. (2004) removes the downward bias <strong>of</strong> st<strong>and</strong>ard LSestimators. Moreover, the IGF based confidence <strong>in</strong>tervals have slightly smaller coverageprobabilities than AMU, <strong>and</strong> the t-statistic is distributed as st<strong>and</strong>ard normal distributionasymptotically.Po<strong>in</strong>t <strong>and</strong> <strong>in</strong>terval estimators are useful statistics for provid<strong>in</strong>g <strong>in</strong>formation to drawconclusions about the duration <strong>of</strong> shocks, unlike hypothesis test<strong>in</strong>g, they are <strong>in</strong>formativewhen a hypothesis is not rejected. Because the IGF estimator is shown to be asymptoticallyst<strong>and</strong>ard normal, the construction <strong>of</strong> confidence <strong>in</strong>tervals is very straightforward.For AR(p) model, impulse-response approach is used, typical examples are Murray <strong>and</strong> Papell(2002) <strong>and</strong> Sekioua (2008). To further the study, based upon the FM asymptotics <strong>of</strong> Phillips(1995), we propose a FM-AR to directly estimate the coefficients <strong>of</strong> any AR(p) process.2. <strong>The</strong> Econometric methodology2.1 IGF estimator for DF-AR(1)Phillips et al. (2004) studies the properties <strong>of</strong> IGF estimator <strong>in</strong> which the <strong>in</strong>struments arenonl<strong>in</strong>ear functions <strong>of</strong> <strong>in</strong>tegrated processes. Framework <strong>of</strong> Phillips et al. (2004) extends theanalysis <strong>of</strong> So <strong>and</strong> Sh<strong>in</strong> (1999) 2 , provid<strong>in</strong>g a more general analysis <strong>of</strong> IV estimation <strong>in</strong>potentially nonstationary autoregressions <strong>and</strong> show<strong>in</strong>g that the Cauchy estimator has anoptimality property <strong>in</strong> the class <strong>of</strong> certa<strong>in</strong> IV procedures.For (1), Phillips et al. (2004) consider the IV estimator <strong>of</strong> given by nt1nt 1F( y ) yt1FY ( ) ytt1 t1Here, is an IV estimator <strong>in</strong> which the <strong>in</strong>strument is generated by the IGF F. In its generalform, the class <strong>of</strong> IV estimators that can be represented by (2) <strong>in</strong>cludes, <strong>of</strong> course, theconventional OLS estimator as a special case with the l<strong>in</strong>ear IGF F(x) = x. However, thispaper will concentrate on IV estimators constructed with various nonl<strong>in</strong>ear IGF’s.<strong>The</strong> bounded optimal IV estimator with asymptotic sign IGF has some nice properties thatthe conventional OLS estimator does not have. <strong>The</strong> estimator yields a t-ratio that has ast<strong>and</strong>ard normal limit distribution when =1, as well as when ||


22Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applicationssectional dependency among currencies, we also follow Chang(2002) to <strong>in</strong>sert a variable csuch that y t-1 Exp(-c|y t-1 |), <strong>and</strong> c is def<strong>in</strong>ed byIV EstimatorsInstrument generat<strong>in</strong>g functions, F()IVh1 sgn(y t-1 )IVh2y t-1 I{|y t-1 |K}+sgn(y t-1 )KI{| y t-1 |>K}IVh3 arctan(y t-1 )IVi1sgn(y t-1 ) I{|y t-1 |K}IVi2y t-1 I{|y t-1 |K}IVi3 y t-1 Exp(-|y t-1 |)Kc s( y ) Twhere s(y t ) denotes the st<strong>and</strong>ard deviation <strong>of</strong> y t , <strong>and</strong> K is a constant fixed at 3. In addition,the recursive de-mean<strong>in</strong>g procedure 3 is also applied.Us<strong>in</strong>g the 0.05 <strong>and</strong> 0.95 quantile functions <strong>of</strong> estimate, we can construct two-sided 90%confidence <strong>in</strong>tervals for the true . <strong>The</strong>se confidence <strong>in</strong>tervals can be used either to providea measure <strong>of</strong> the accuracy <strong>of</strong> or to construct the conventional exact one- or two-sided tests<strong>of</strong> the null hypothesis that = 0 . In this paper, we use such symmetric confidence <strong>in</strong>tervalsonly to provide a measure <strong>of</strong> the accuracy <strong>of</strong> estimate.2.2 IGF estimator for ADF-AR(p)In addition, the presence <strong>of</strong> serial correlation (typical <strong>in</strong> economic time series) means that (1)will <strong>of</strong>ten not be appropriate. In such cases, (1) is augmented to be an AR(p) model byadd<strong>in</strong>g lagged first-order difference. Hence, the start<strong>in</strong>g po<strong>in</strong>t <strong>of</strong> this analysis is thefollow<strong>in</strong>g ADF regression:tpy y y(3)t t1k tk tk1Similarly, (3) is estimated by IGF. For augmented differenced lagged variables, <strong>in</strong>strumentsare themselves without IGF transformation. Subsequently, we then def<strong>in</strong>e the matricesbelowyp y1 p xp 1 p 1 y , y , X ,ε y y x T T1 T T collects the lagged difference terms. <strong>The</strong>n the augmented ARwhere xt yt1 ,...... ytpregression (3) can be written <strong>in</strong> matrix form as3 See eq.(25) <strong>in</strong> Phillips et al. (2004, p.231).


Instrument Generat<strong>in</strong>g Function<strong>and</strong> Analysis <strong>of</strong> Persistent Economic Times Series: <strong>The</strong>ory <strong>and</strong> Application 23y y X Y (4)where ( 1,....... p ) , Y ( y , X),<strong>and</strong> ( , ) . For equation (4), IV estimator isconstructed below1 ˆ Fy ( ) y Fy ( ) X Fy ( ) yˆ Xy XX Xy .where Fy ( ) Fy ( p), Fy ( T)11 T TUnder the null, we have B A , where1ATFy ( ) Fy ( ) XXX ( ) XT T T1T F( yt1) t F( yt1)xt xtxt xttt1 t1 t1 t11BTFy ( ) y Fy ( ) XXX ( ) Xy T T T1T Fy ( ) y Fy ( ) x xx xy t1 t1 t1 t t t t t1t1 t1 t1 t1<strong>and</strong> the variance <strong>of</strong>AT is given by2 ECT , where1CTFy ( ) Fy ( ) Fy ( ) XXX ( ) XFy ( )T T T1T2 Fyt1 Fyt1 xt xx t t xFy t t1t1 t1 t1 t1( ) ( ) ( ) For differenced lagged variables, themselves are used as the <strong>in</strong>struments without IGFtransformation, details are expla<strong>in</strong>ed <strong>in</strong> Chang(2002). <strong>The</strong> half-life calculated from the value<strong>of</strong> (1) assumes that shocks to the data decay monotonically, which is <strong>in</strong>appropriate for ADFregressions represented by (3), s<strong>in</strong>ce <strong>in</strong> general shocks to an AR(p) will not decay at aconstant rate. Murray <strong>and</strong> Papell (2002) calculate the half-life from the impulse responsefunction <strong>of</strong> an AR(p) below,py c y (4)t k tk tk1From the IGF estimates <strong>of</strong> (3), coefficients <strong>of</strong> (4) can be recalculated as follows:1 1, 2 ( 1 2), 3 ( 2 3), <strong>and</strong> 1 . (5)pp


24Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> ApplicationsWhen the coefficients are obta<strong>in</strong>ed, the k-period impulse response function (irf thereafter)for univariate AR(p) regression can be calculated. For convenience, we name (4) by ADF-AR(p).(5) is widely used, for example, Murray <strong>and</strong> Papell (2002), however, not only is it subject tostrict restriction, but also bias if some <strong>of</strong> right-h<strong>and</strong>-side variables <strong>of</strong> (4) are co-<strong>in</strong>tegrated.<strong>The</strong>refore, <strong>in</strong>stead <strong>of</strong> us<strong>in</strong>g (3) <strong>and</strong> (5) to <strong>in</strong>directly calculate the coefficients <strong>of</strong> (4), wepropose a Fully-Modified AR (p) to estimate (4) directly, the model is derived from Fully-Modified VAR <strong>of</strong> Phillips (1995). Section below cont<strong>in</strong>ues the study.2.3 Unrestricted fully-modified AR(p)Phillips’ (1995) FM-VAR is a level system regression with/without error correction terms(differenced terms). FM-VAR <strong>of</strong> Phillips (1995) generalized the asymptotics <strong>of</strong> Phillips <strong>and</strong>Hansen (1990), allow<strong>in</strong>g full rank I(1) regressors <strong>and</strong> possible co<strong>in</strong>tegration existed amonglagged dependent variables. Mostly important, the asymptotics <strong>of</strong> FM-VAR is normal, ormixed normal, which allows us to construct confidence <strong>in</strong>tervals <strong>and</strong> half life. <strong>The</strong>methodology for FM-AR(p) is illustrated below.y ay y u aAy u(6)t 1 t1 p tp 0t t0twhere A is an 1p coefficient vector <strong>and</strong> y t- is a p(p=p 1 +p 2 )-dimensional vector <strong>of</strong> lagged y twhich are partitioned below:H y y up 1 11 t1, t1tH y y up 2 12 t2, t2tHere H=[H 1 , H 2 ] is pp orthogonal matrix <strong>and</strong> rotates the regressor space <strong>in</strong> (6) so that themodel has the alternative formy A y A y u(7)t 1 1, t2 2, t0tHere A 1 =AH 1 <strong>and</strong> A 2 =AH 2 . <strong>The</strong> form <strong>of</strong> (7) usefully separates out the I(0) <strong>and</strong> I(1)components <strong>of</strong> the regressors <strong>in</strong> (6). However, the direction (H 1 ) <strong>in</strong> which the regressors arestationary will not be generally known <strong>in</strong> advance, not even will the rank <strong>of</strong> theco<strong>in</strong>tegrat<strong>in</strong>g space <strong>of</strong> the regressors. Phillips’ (1995) fully-modified correction has twosteps:<strong>The</strong> first step is to correct for the serial correlation to the LS estimatorˆA y 1tyt ytyt<strong>of</strong>(7). <strong>The</strong> endogeneity correction is achieved by modify<strong>in</strong>g the dependent variable y t <strong>in</strong> (7)with the transformationy y ˆˆ y(8)1t t 0yt ytyttIn (8), ˆ denotes the kernel estimate <strong>of</strong> the long-run (lr) covariances <strong>of</strong> the variablesdenoted by the subscript:ˆ 0y lr cov( u0, )tt yt<strong>and</strong> ˆ y cov( , )t y lr y tt y t. (8)leads us to estimate the equation below


Instrument Generat<strong>in</strong>g Function<strong>and</strong> Analysis <strong>of</strong> Persistent Economic Times Series: <strong>The</strong>ory <strong>and</strong> Application 25y ˆ ˆ y Ay u u1 1t 0y t yt y tt t 0t 0222 2tPhillips (1995, Pp. 1033-1034) shown that this transformation reduces to the ideal correctionasymptotically, at least as far as the nonstationary components y 2,t- are concerned. <strong>The</strong>stationary components y 1,t- are present <strong>in</strong> differenced or I(-1) form <strong>in</strong> this transformation <strong>and</strong>have no effects asymptotically. <strong>The</strong>refore, we can achieve an endogeneity correction withknow<strong>in</strong>g the actual directions <strong>in</strong> which it is required or even the number <strong>of</strong> nonstationaryregressors that need to be dealt with.Secondly, the serial correction term has the formˆ ˆ ˆ ˆ 1 ˆ0y t 0y t 0y t yty t ytytwhere ˆ0y <strong>and</strong> ˆ t y t y denote the kernel estimates <strong>of</strong> the one-sided long-run covariancest ˆ lr cov ( u , y ) <strong>and</strong> ˆ lr cov ( y , y ) .0yt 0t tytyt t tComb<strong>in</strong><strong>in</strong>g the endoneneity <strong>and</strong> serial corrections we have the FM formula for theparameter estimates1 ` ˆ ` 0 Aˆ y y y y T (9)t t t t y t For (9), the limit theory <strong>of</strong> FM estimates <strong>of</strong> the stationary components <strong>of</strong> the regressors isequivalent to that <strong>of</strong> LS, while the FM estimates <strong>of</strong> the nonstationary components reta<strong>in</strong>their optimality properties as derived <strong>in</strong> Phillips <strong>and</strong> Hansen (1990); that is, they areasymptotically equivalent to the MLE estimates <strong>of</strong> the co-<strong>in</strong>tegrat<strong>in</strong>g matrix.For the f<strong>in</strong>ite sample property <strong>of</strong> FM-AR, Appendix <strong>of</strong>fers a simulation study illustrat<strong>in</strong>g agood performance <strong>of</strong> this estimator <strong>in</strong> calculat<strong>in</strong>g half-life <strong>of</strong> near I(1) process.3. Empirical resultsTo illustrate these approaches, BIS real effective exchange rates (REER thereafter) <strong>of</strong> foureconomies (Germany, Japan, UK, <strong>and</strong> USA) are used, samples range from 1994M1 to2010M12. BIS’ REER is CPI-based <strong>and</strong> is a broad <strong>in</strong>dex <strong>of</strong> monthly averages, with 2005=100.Figure 1 plots the time series plot <strong>of</strong> them, with a horizontal l<strong>in</strong>e <strong>of</strong> the base year <strong>in</strong>dex. <strong>The</strong>Y-axis also illustrates the histogram to depict the distribution property <strong>of</strong> these data. <strong>The</strong>common feature <strong>of</strong> them is an apparent behavior <strong>of</strong> stochastic trend.In Table 1, the upper panel DF-AR(1) presents the results <strong>of</strong> (1); the lower panel ADF-AR(p)summarizes those <strong>of</strong> (5), <strong>and</strong> the BIC criterion returns unanimously 2 lags. Compar<strong>in</strong>g bothresults, tak<strong>in</strong>g Germany as an example, expressed <strong>in</strong> years, its half life takes 12.55 for DF-AR(1) <strong>and</strong> substantially drops to 0.916 for ADF-AR(2); similar f<strong>in</strong>d<strong>in</strong>g is also found <strong>in</strong> Japan.UK <strong>and</strong> USA does not have f<strong>in</strong>ite bounds. Apparently, the dynamic lag structure issubstantial.Table 2 <strong>of</strong> FM-AR(2) tabulates more results. Unrestricted FM-AR(2) yields f<strong>in</strong>ite bounds <strong>of</strong>half-lives for all four economies, most <strong>of</strong> them are roughly less than two years. To be more<strong>in</strong>formative, Figure 2 graphs the impulse response plot <strong>of</strong> Germany, expressed <strong>in</strong> month;clearly, the impulse response function <strong>of</strong> Germany has a rather wide confidence <strong>in</strong>terval.


26Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> ApplicationsGERMANY JAPAN UK USAMean 101.40 108.02 95.97 99.52Median 100.91 106.55 99.93 98.83Maximum 116.79 151.11 107.81 116.00M<strong>in</strong>imum 90.91 79.68 75.88 86.53Std. Dev. 5.50 14.98 8.91 7.93Skewness 0.63 0.42 -0.68 0.31Kurtosis 3.09 2.99 2.04 2.10JB(Prob.) 13.71( 0.001) 6.073(0.048) 23.72(0.000) 10.18(0.006)For each currency, there are 204 observations. JB(Prob.) is the Jarque-Bera statistic for normality withprobability value <strong>in</strong> the parenthesis.Table 1. Summary statisticDF-AR(1) Std mean HL HL, 90% CIGermany 0.995 0.028 12.55 0.95 Japan 0.984 0.028 3.58 0.78 UK 1.025 0.014 15.59 USA 1.014 0.014 4.29 ADF-AR(2)+ 1 2 - 1 mean HL HL, 90% CIGermany 1.180 -0.253 0.916 0.541 Japan 1.272 -0.330 1.132 0.624 UK 1.162 -0.159 USA 1.332 -0.340 1.911 Note. HL =half-lives. BIC suggests two lags for four economies.Table 2. IGF estimation results, <strong>in</strong> years, 1994M1-2010M12.H LH LH UH U 1 2 mean HL HL, 90% CIGermany 1.121 -0.156 1.789 0.376 Japan 1.292 -0.335 1.525 0.356 UK 1.158 -0.191 1.926 0.258 USA 1.270 -0.298 2.253 0.406 Table 3. FM-AR(2) estimation results, <strong>in</strong> years, 1994M1-2010M12.H LH U


Instrument Generat<strong>in</strong>g Function<strong>and</strong> Analysis <strong>of</strong> Persistent Economic Times Series: <strong>The</strong>ory <strong>and</strong> Application 27GERMANYJAPAN12016011514011012010510010095809094 96 98 00 02 04 06 08 106094 96 98 00 02 04 06 08 10UKUSA11012011510011090105100809590708594 96 98 00 02 04 06 08 10Fig. 1. Time series plot <strong>of</strong> four currencies’ REER94 96 98 00 02 04 06 08 1080meanLower BoundUpper Bound6040201.2 01.00.80.60.40.20.02 4 6 8 10 12 14 16 18 20 22 24 26 28 30Fig. 2. Impulse-response plot <strong>of</strong> Germany, FM-AR(2), <strong>in</strong> month.4. Conclusion<strong>The</strong> empirical study <strong>of</strong> time series persistence uses two ma<strong>in</strong> approaches: unit root tests <strong>and</strong>half-life. However, reliance on unit root tests does NOT provide a measure <strong>of</strong> uncerta<strong>in</strong>ty <strong>of</strong>the estimates <strong>of</strong> f<strong>in</strong>iteness or permanence <strong>of</strong> <strong>in</strong>novations because a rejection <strong>of</strong> the unit rootnull could still be consistent with a stationary process with highly persistent shocks. Because


28Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications<strong>of</strong> near-unit root bias <strong>and</strong> result<strong>in</strong>g the lack <strong>of</strong> distribution, the empirical studies generallyapply Andrews’ (1993) median unbiasedness method to estimate the AR(1) coefficient to<strong>in</strong>vestigate the persistence behavior.For AR(1) case, this paper contributes to the literature by apply<strong>in</strong>g the IGF approach <strong>of</strong>Phillips et al. (2004) to estimate the coefficients <strong>of</strong> near unit root process, IGF estimator isproved to be normal asymptotically, hence it is very easy to construct confidence <strong>in</strong>tervals.For AR(p) case, moreover, <strong>in</strong>stead <strong>of</strong> recalculation, we propose a unrestricted FM-AR(p)model, a slight extension <strong>of</strong> Phillips’ (1995) FM-VAR, to estimate coefficients directly.Our empirical illustration <strong>of</strong> real effective exchange rate <strong>in</strong>dicates that FM-AR(p) is a useful<strong>and</strong> easy-to-use method to exam<strong>in</strong>e the econometric persistence.5. Appendix: <strong>The</strong> f<strong>in</strong>ite sample properties <strong>of</strong> FM-ARThis paper shows that a FM estimator can ameliorate the small sample biases that arise fromnear unit root bias. Our attention here is focused on the class <strong>of</strong> dynamic AR(p). A MonteCarlo simulation is used here to <strong>in</strong>vestigate the performance, our results <strong>in</strong>dicate that FMestimator successfully reduces the small-sample bias.Assum<strong>in</strong>g { yt} t 0 is governed by a AR(3) time series process generated from (, 2 ) = (0, 1),which satisfies the data-generat<strong>in</strong>g process specified below:y y y y (1)t 1 t1 2 t2 3 t3twhere t i.i.d.. <strong>and</strong> ’s represent the associated parameters, <strong>and</strong> is the st<strong>and</strong>arddeviation. In our simulation, we generate an AR(3) process. <strong>The</strong> summation <strong>of</strong> the threecoefficients measures the degree <strong>of</strong> persistence, the vector is parameterized belowDegree <strong>of</strong> Persistence 1: { 1 , 2, 3 } = {0.90, 0.085, 0.015},Degree <strong>of</strong> Persistence 2: { 1 , 2, 3 } = {0.90, 0.050, 0.015}Degree <strong>of</strong> Persistence 3: { 1 , 2, 3 }= {0.85, 0.050, 0.015}<strong>and</strong>T{ 200, 400, 800, 1500, 3000}where T represents the vector <strong>of</strong> sampl<strong>in</strong>g size that are used <strong>in</strong> practice. <strong>The</strong> DGPs arecharacterized by a modest change <strong>in</strong> the <strong>in</strong>novation variance but allow for drastic changes<strong>in</strong> others.Table A1 reports the characteristics <strong>of</strong> the f<strong>in</strong>ite-sample distribution <strong>of</strong> both estimators <strong>of</strong> theelements <strong>of</strong> estimates. <strong>The</strong>se <strong>in</strong>clude the deviation <strong>of</strong> the estimate from the true parametervalue, or bias, as well as measures <strong>of</strong> skewness <strong>and</strong> kurtosis. I compare the bias <strong>and</strong>normality to illustrate the problem. <strong>The</strong>re are several ma<strong>in</strong> results.Firstly, the biases are decreas<strong>in</strong>g function <strong>of</strong> sample sizes. Even <strong>in</strong> small samples around 200<strong>and</strong> 400, the biases are <strong>in</strong> the range <strong>of</strong> 10 -2 . <strong>The</strong> bias for FM-AR is quite small.Secondly, the variance bias exhibits the similar conclusion. AR(3) is generated from (0,1), theempirical bias is <strong>in</strong> the range <strong>of</strong> 10 -3 , <strong>and</strong> is a decreas<strong>in</strong>g function <strong>of</strong> sample size.F<strong>in</strong>ally, the normality property <strong>of</strong> distribution is drawn from skewness <strong>and</strong> kurtosis.Unfortunately, no regular pattern is found among three parameter estimates <strong>and</strong> is relatedto the persistence <strong>of</strong> parameter vector designed; <strong>in</strong> general, skewness is close to zero whichgives normality an acceptable condition, although the excess kurtosis (>3) is found.As a result, FM-AR is a feasible estimator to directly estimate AR(p), whose empiricalapplications also calls for further studies <strong>in</strong> the future.


30Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> ApplicationsPapell, David H. (1997) Search<strong>in</strong>g for stationarity: purchas<strong>in</strong>g power parity under thecurrent float. Journal <strong>of</strong> International Economics, 43, 313–323.Phillips P. C. B., B.E. Hansen (1990) Statistical <strong>in</strong>ference <strong>in</strong> <strong>in</strong>strumental variables with I(1)regressors. Review <strong>of</strong> Economic Studies, 57(2), 99-125.Phillips P. C. B., Park, J. Y., Chang Y.(2004) Nonl<strong>in</strong>ear <strong>in</strong>strument variable estimation <strong>of</strong> anautoregression. Journal <strong>of</strong> Econometrics 118, 219-246.Phillips P. C. B. (1995) Fully-modified least squares <strong>and</strong> vector autoregression. Econometrica,63(5), 1023-1078.So, B.S., Sh<strong>in</strong>, D.W. (1999) Recursive mean adjustment <strong>in</strong> time-series <strong>in</strong>ferences. Statistics &Probability Letters 43, 65–73.


Recent Developments <strong>in</strong> SeasonalVolatility ModelsJulieta Frank 1 , Melody Ghahramani 2 <strong>and</strong> A. Thavaneswaran 11 University <strong>of</strong> Manitoba2 University <strong>of</strong> W<strong>in</strong>nipegCanada31. IntroductionIt is well-known that many f<strong>in</strong>ancial time series such as stock returns exhibit leptokurtosis<strong>and</strong> time-vary<strong>in</strong>g volatility (Bollerslev, 1986; Engle, 1982; Nicholls & Qu<strong>in</strong>n, 1982). <strong>The</strong>generalized autoregressive conditional heteroscedasticity (GARCH) <strong>and</strong> the r<strong>and</strong>omcoefficient autoregressive (RCA) models have been extensively used to capture thetime-vary<strong>in</strong>g behavior <strong>of</strong> the volatility. Studies us<strong>in</strong>g GARCH models commonly assumethat the time series is conditionally normally distributed; however, the kurtosis implied bythe normal GARCH tends to be lower than the sample kurtosis observed <strong>in</strong> many time series(Bollerslev, 1986). Thavaneswaran et al. (2005a) use an ARMA representation to derive thekurtosis <strong>of</strong> various classes <strong>of</strong> GARCH models such as power GARCH, non-Gaussian GARCH,non-stationary <strong>and</strong> r<strong>and</strong>om coefficient GARCH. Recently, Thavaneswaran et al. (2009) haveextended the results to stationary RCA processes with GARCH errors <strong>and</strong> Paseka et al. (2010)further extended the results to RCA processes with stochastic volatility (SV) errors.Seasonal behavior is commonly observed <strong>in</strong> f<strong>in</strong>ancial time series, as well as <strong>in</strong> currency<strong>and</strong> commodity markets. <strong>The</strong> open<strong>in</strong>g <strong>and</strong> closure <strong>of</strong> the markets, time-<strong>of</strong>-the-day <strong>and</strong>day-<strong>of</strong>-the-week effects, weekends <strong>and</strong> vacation periods cause changes <strong>in</strong> the trad<strong>in</strong>g volumethat translates <strong>in</strong>to regular changes <strong>in</strong> price variability. F<strong>in</strong>ancial, currency, <strong>and</strong> commoditydata also respond to new <strong>in</strong>formation enter<strong>in</strong>g <strong>in</strong>to the market, which usually followseasonal patterns (Frank & Garcia, 2009). Recently there has been grow<strong>in</strong>g <strong>in</strong>terest <strong>in</strong> us<strong>in</strong>gseasonal volatility models, for example Bollerslev (1996), Baillie & Bollerslev (1990) <strong>and</strong>Franses & Paap (2000). Doshi et al. (2011) discuss the kurtosis <strong>and</strong> volatility forecasts forseasonal GARCH models. Ghysels & Osborn (2001) review studies performed on seasonalvolatility behavior <strong>in</strong> several markets. Most <strong>of</strong> the studies use GARCH models with dummyvariables <strong>in</strong> the volatility equation, <strong>and</strong> a few <strong>of</strong> them have been extended to a more flexibleform such as the periodic GARCH. However, even though much research has been performedon volatility models applied to market data such as stock returns, more general specificationsaccount<strong>in</strong>g for seasonal volatility have been little explored.First, we derive the kurtosis <strong>of</strong> a simple time series model with seasonal behavior <strong>in</strong> the mean.<strong>The</strong>n we <strong>in</strong>troduce various classes <strong>of</strong> seasonal volatility models <strong>and</strong> study the moments,forecast error variance, <strong>and</strong> discuss applications <strong>in</strong> option pric<strong>in</strong>g. We extend the resultsfor non-seasonal volatility models to seasonal volatility models. For the seasonal GARCH


Recent Developments <strong>in</strong> SeasonalVolatility Models 3Recent Developments <strong>in</strong> Seasonal Volatility Models33qθ(B) =1 − ∑ θ i B i P, Φ(L) =1 − ∑ Φ i L i Q, Θ(L) =1 − ∑ Θ i L i , L = B s , <strong>and</strong> all coefficients arei=1i=1i=1assumed to be positive.Lett<strong>in</strong>g u t = ɛ 2 t − h t <strong>and</strong> σu 2 = var(u t ), (4) may be written as,φ p (B)Φ P (L)ɛ 2 t = ω + θ q (B)Θ Q (L)u t , (5)which has a seasonal ARMA(p, q)x(P, Q) s representation for ɛ 2 t . Note that whenP = Q = 0, (5) simplifies to an ARMA(max{p, q}, q) representation for ɛ 2 t , correspond<strong>in</strong>g tothe general GARCH(p, q)model.We assume that |β| < 1; thus, y t as given <strong>in</strong> (2) is stationary. <strong>The</strong> mov<strong>in</strong>g averagerepresentation is y t = ∑ ∞ j=0 ψ jɛ t−j where {ψ j } is a sequence <strong>of</strong> constants <strong>and</strong> ∑ ∞ j=0 ψ2 j< ∞.<strong>The</strong> ψ j ’s are obta<strong>in</strong>ed from (1 − βB)ψ(B) =1whereψ(B) =1 + ∑ ∞ j=1 ψ jB j .We also assume that all the zeros <strong>of</strong> the polynomial φ(B)Φ(L) lie outside the unit circle; thus,ɛ 2 t as given <strong>in</strong> (5) is stationary. <strong>The</strong> mov<strong>in</strong>g average representation is ɛ2 t = μ + ∑ ∞ j=0 Ψ ju t−jwhere {Ψ j } is a sequence <strong>of</strong> constants <strong>and</strong> ∑ ∞ j=0 Ψ2 j< ∞. <strong>The</strong> Ψ j ’s are obta<strong>in</strong>ed fromΨ(B)φ(B)Φ(L) =θ(B)Θ(L) where Ψ(B) =1 + ∑ ∞ j=1 Ψ jB j .Next, we provide the kurtosis, the forecast, <strong>and</strong> the forecast error variance for anAR(1)-seasonal GARCH(p, q)x(P, Q) s .Lemma 3.1. For the stationary AR(1) process y t with multiplicative seasonal GARCH<strong>in</strong>novations as <strong>in</strong> (2)– (4) we have the follow<strong>in</strong>g relationships:(i) E(y 2 t )= E(ɛ2 t )1 − β 2 , (6)(ii) E(y 4 t )= 6β2 [E(ɛ 2 t )]2 +(1 − β 2 )E(ɛ 4 t )(1 − β 2 )(1 − β 4 , (7))(iii) K (y) = E(y4 t )[E(y 2 t )]2 = 6β2 (1 − β 2 )1 − β 4 + (1 − β2 ) 21 − β 4 K (ɛ) . (8)<strong>The</strong> kurtosis for ɛ t , K (ɛ) ,isgivenbelow.Lemma 3.2. For the stationary process (3) with f<strong>in</strong>ite fourth moment, the kurtosis K (ɛ) is givenby:(a) K (ɛ) E(Zt 4 =)E(Zt 4 ∞ .) − [E(Z4 t ) − 1] ∑ Ψ 2 jj=0(b) <strong>The</strong> variance <strong>of</strong> the ɛ 2 tprocess is given by γɛ20 = ∞∑j=0Ψ 2 j σ2 uwhere σu 2 = μ2 (K (ɛ) − 1)∞ <strong>and</strong> μ = E(ɛ 2∑ Ψ 2 t )=ω() .pPj1 − ∑ φ i)(1 − ∑ Φ ij=0i=1i=1Part (a) is derived <strong>in</strong> Thavaneswaran et al. (2005a) where examples are given with Ψ-weightsderived for non-seasonal GARCH models. <strong>The</strong> Ψ-weights for examples <strong>of</strong> seasonal GARCHmodels, <strong>and</strong> the pro<strong>of</strong> <strong>of</strong> part (b), are given <strong>in</strong> Doshi et al. (2011).


Recent Developments <strong>in</strong> SeasonalRecent Volatility Models Developments <strong>in</strong> Seasonal Volatility Models355Example 3.3. For a stationary autoregressive process <strong>of</strong> order one, AR(1), with multiplicativeseasonal GARCH (1, 0)x(1, 0) s errors <strong>of</strong> the form,y t = βy t−1 + ɛ tɛ t = √ h t Z t(1 − φB)(1 − ΦL)ɛ 2 t = ω + u twhere φ is the autoregressive parameter <strong>and</strong> Φ is the seasonal autoregressive parameter. <strong>The</strong>Ψ-weights given <strong>in</strong> Doshi et al. (2011) are as follows: Ψ 1 = φ, Ψ 2 = φ 2 ,...,Ψ s−1 = φ s−1 , Ψ s =φ 2 + Φ,...,Ψ j = φΨ j−1 + ΦΨ j−s − φΦΨ j−s .Itcanbeshownthat∑ ∞ j=0 Ψ2 j= 1 + 2φs Φ 2 + Φ 21 − φ 2 .<strong>The</strong>n, the kurtosis <strong>of</strong> y t is:K (y) = 6β2 (1 − β 2 )(1 − β 4 + (1 − β2 ) 2E(Zt 4)) (1 − β 4 ()1 + 2φE(Zt 4) − [E(Z4 t ) − 1] s Φ + Φ 2 ) ,1 − φ 2which for a conditionally normally distributed Z t reduces to:K (y) = 6β2 (1 − β 2 )(1 − β 4 + (1 − β2 ) 2 3(1 − φ 2 )) (1 − β 4 ) (1 − 3φ 2 − 4φ s Φ − 2Φ 2 ) .Forecast error varianceThavaneswaran et al. (2005a) derive the expression for the forecast error variance <strong>of</strong> variousclasses <strong>of</strong> zero mean GARCH(p, q) processes, <strong>in</strong> terms <strong>of</strong> the kurtosis <strong>and</strong> Ψ-weights.Thavaneswaran & Ghahramani (2008) extend the results for ARMA (p, q) processes withGARCH (P, Q) errors. In this section we extend the results to AR models with multiplicativeseasonal GARCH(p, q)x(P, Q) s errors.<strong>The</strong>orem 3.1. Let y n (l) be the l-steps-ahead m<strong>in</strong>imum mean square forecast <strong>of</strong> y n+l <strong>and</strong> lete (y)n (l) =y n+l − y n (l) be the correspond<strong>in</strong>g forecast error. <strong>The</strong> variance <strong>of</strong> the l-steps-aheadforecast error <strong>of</strong> y n+l for the AR(1) model with seasonal GARCH errors as given <strong>in</strong> (2)- (4) is:Var[e (y)l−1ωn (l)] = ()pP∑ ψj=01 − ∑ φ i)(1 2 j . (10)− ∑ Φ ii=1i=1Pro<strong>of</strong>. <strong>The</strong> theorem follows from the fact that for a stationary process with uncorrelated errornoise ɛ t the variance <strong>of</strong> the l-steps ahead forecast error is σɛ 2 ∑ l−1j=0 ψ2 j <strong>and</strong> from part (b) <strong>of</strong>Lemma 3.2.We now have expressions for the variance <strong>of</strong> the l-steps-ahead forecast error <strong>of</strong> y n+l for thepreviously discussed AR(1)-GARCH(p, q)x(P, Q) s models:AR(1)-GARCH(0, 1)x(0, 1) sVar[e (y)l−1n (l)] = ω ∑ β 2jj=0


36 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications6 Will-be-set-by-IN-TECHAR(1)-GARCH(0, 1)x(1, 0) sAR(1)-GARCH(1, 0)x(1, 0) sVar[e (y)n (l)] = ω l−11 − ΦVar[e (y)n (l)] =∑j=0β 2jl−1ω(1 − φ)(1 − Φ)∑j=0β 2j .In the literature on time series analysis, the error variance is estimated by the residual sum<strong>of</strong> squares. If we denote the squared residual as Y t =(y t − ˆβy t−1 ) 2 , then we can forecast theconditional variance, var(y t |y t−1 ,...)=h t ,byus<strong>in</strong>gY 1 ,...,Y t−1 .<strong>The</strong>orem 3.2. Let Y n (l) be the l-steps-ahead m<strong>in</strong>imum mean square forecast <strong>of</strong> Y n+l <strong>and</strong> lete (Y)n (l) =Y n+l − Y n (l) be the correspond<strong>in</strong>g forecast error. <strong>The</strong> variance <strong>of</strong> the l-steps-aheadforecast error <strong>of</strong> Y n+l is given by:Var[e (Y)n (l)] = σu2 l−1∑j=0Ψ 2 j = ⎡⎣ ∞ ∑j=0⎡ ⎤ω⎤2[ ]p 2 ]Ψ 2 P 2[K⎦j 1 − ∑ φ i[1 (ɛ) − 1] ⎣ l−1∑ Ψ 2 ⎦j (11)j=0− ∑ Φ ii=1i=1where, from (8), K (ɛ) =1 − β4(1 − β 2 ) 2 K(y) − 6β21 − β 2 .Pro<strong>of</strong>. <strong>The</strong> pro<strong>of</strong> follows from part (b) <strong>of</strong> Lemma 3.2.We now have expressions for the variance <strong>of</strong> the l-steps-ahead forecast error <strong>of</strong> Y n+l for thepreviously discussed AR(1)-GARCH(p, q)x(P, Q) s models:AR(1)-GARCH(0, 1)x(0, 1) sAR(1)-GARCH(0, 1)x(1, 0) sAR(1)-GARCH(1, 0)x(1, 0) sVar[e (Y)n (l)] = (K(ɛ) − 1)μ 2 l−1(1 + θ 2 )(1 + Θ 2 )∑ Ψ 2 jj=0Var[e (Y)n (l)] = (K(ɛ) − 1)μ 2 (1 − Φ 2 l−1)1 +∑θ 2 Ψ 2 jj=0Var[e (Y)n (l)] = (K(ɛ) − 1)μ 2 (1 − φ 2 l−1)1 + 2φ s Φ + Φ∑ 2 Ψ 2 jj=0which are similar to the expressions given <strong>in</strong> Doshi et al. (2011). Here, K (ɛ) is given <strong>in</strong> <strong>The</strong>orem3.2. <strong>and</strong> expressions for K (y) are given <strong>in</strong> Examples 3.1, 3.2, <strong>and</strong> 3.3.4. RCA models with seasonal GARCH errors<strong>The</strong> r<strong>and</strong>om coefficient autoregressive (RCA) model as proposed by Nicholls & Qu<strong>in</strong>n (1982)has the form,y t =(β + b t )y t−1 + ɛ t (12)( ) (( ( ))bt 0 σ 2where ∼ N , b 0ɛ t 0)0 σɛ2 <strong>and</strong> β 2 + σb 2 < 1.


Recent Developments <strong>in</strong> SeasonalRecent Volatility Models Developments <strong>in</strong> Seasonal Volatility Models377ɛ 2 t = ω +(1 − θB)(1 − ΘL)u tThavaneswaran et al. (2009) derive the moments for the RCA model with GARCH(p, q)errors.Here we propose the RCA model with seasonal GARCH <strong>in</strong>novations <strong>of</strong> the follow<strong>in</strong>g form,y t =(β + b t )y t−1 + ɛ t (13)ɛ t = √ h t Z t (14)θ(B)Θ(L)h t = ω + α(B)ɛ 2 t (15)where Z t , θ(B), Θ(L), α(B) were def<strong>in</strong>ed <strong>in</strong> Section 2.<strong>The</strong> general expression for the kurtosis K (y) parallels the one <strong>in</strong> Thavaneswaran et al. (2009)for non-seasonal GARCH <strong>in</strong>novations <strong>and</strong> can be written as follows.Lemma 4.1. For the stationary RCA process y t with GARCH <strong>in</strong>novations as <strong>in</strong> (13)– (15) wehave the follow<strong>in</strong>g relationships:(i) E(y 2 E(ɛ 2 tt )=1 − (β 2 + σb 2) , (16)(ii) E(y 4 t )= 6(β2 + σb 2)[E(ɛ2 t )]2 +[1 − (β 2 + σb 2)]E(ɛ4 t )1 − (3σb 4 + β4 + 6β 2 σb 2)[1 − (β2 + σb 2)] , (17)(iii) K (y) = 6(β2 + σb 2)[1 − (β2 + σb 2)][1 − (β 2 + σb 21 − (3σb 4 + β4 + 6β 2 σb 2) +1 − (3σb 4 + β4 + 6β 2 σb 2) K(ɛ) . (18)If Z t is normally distributed, then the above equations can be written as:(i) E(y 2 E(h t )t )=1 − (β 2 + σb 2) , (19)(ii) E(y 4 6(β 2 + σb 2t )=[1 − (β 2 + σb 2)](1 − 6β2 σb 2 − β4 − 3σb 4) [E(h t)] 2 3E(h 2 t+1 − 6β 2 σb 2 − β4 − 3σb4 , (20)(iii) K (y) = 6(β2 + σb 2)[1 − (β2 + σb 2)]3(1 − β 2 − σb 21 − 6β 2 σb 2 − β4 − 3σb4 +E(h 2 t )1 − 6β 2 σb 2 − β4 − 3σb4 [E(h t )] 2 . (21)Thavaneswaran et al. (2005a) show that:E(h 2 t )[E(h t )] 2 = 1E(Zt 4) − [E(Z4 t ) − 1] ,∑∞ j=0 Ψ2 j1which for a conditionally normally distributed ɛ t reduces to3 − 2 ∑ ∞ .j=0 Ψ2 jExample 4.1. RCA(1) with multiplicative seasonal GARCH (0,1)x(0,1) processy t =(β + b t )y t−1 + ɛ tɛ t = √ h t Z t


38 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications8 Will-be-set-by-IN-TECHwhere u t = ɛ 2 t − h t.<strong>The</strong> Ψ-weights are given <strong>in</strong> example 3.1. <strong>The</strong>n, the kurtosis <strong>of</strong> y t for aconditionally normally distributed Z t is:K (y) = 6(σ2 b + β2 )(1 − β 2 − σ 2 b )1 − 6β 2 σ 2 b − β4 − 3σ 4 b+3(1 − β 2 − σ 2 b )(1 − 6β 2 σ 2 b − β4 − 3σ 4 b )[3 − 2(1 + θ2 )(1 + Θ 2 )] .Example 4.2. RCA(1) with multiplicative seasonal GARCH (0,1)x(1,0) processy t =(β + b t )y t−1 + ɛ tɛ t = √ h t Z t(1 − ΦL)ɛ 2 t = ω +(1 − θB)u t<strong>The</strong> Ψ-weights are given <strong>in</strong> example 3.2. <strong>The</strong>n, the kurtosis <strong>of</strong> y t for a conditionally normallydistributed Z t is:K (y) = 6(σ2 b + β2 )(1 − β 2 − σ 2 b )1 − 6β 2 σ 2 b − β4 − 3σ 4 b+3(1 − β 2 − σ 2 b )(1 − 6β 2 σ 2 b − β4 − 3σ 4 b ) [3 − 2Example 4.3. RCA(1) with multiplicative seasonal GARCH (1,0)x(1,0) processy t =(β + b t )y t−1 + ɛ tɛ t = √ h t Z t(1 − φB)(1 − ΦL)ɛ 2 t = ω + u t( 1 + θ 21 − Φ 2 )] .<strong>The</strong> Ψ-weights are given <strong>in</strong> example 3.3. <strong>The</strong>n, the kurtosis <strong>of</strong> y t for a conditionally normallydistributed Z t is:K (y) = 6(σ2 b + β2 )(1 − β 2 − σ 2 b )1 − 6β 2 σ 2 b − β4 − 3σ 4 b3(1 − β 2 − σ 2+b( )1 + 2φ(1 − 6β 2 σb 2 − β4 − 3σb [3 4) − s Φ + Φ 2 )].21 − Φ 2Forecast error varianceThavaneswaran & Ghahramani (2008) derive the expression for the variance <strong>of</strong> the forecasterror for a RCA(1) process with non-seasonal GARCH (1,1) errors. In this section we exp<strong>and</strong>the results for the more general RCA(1) process with seasonal GARCH(p, q)x(P, Q) s errors.<strong>The</strong>orem 4.1. Let y n (l) be the l-steps-ahead m<strong>in</strong>imum mean square forecast <strong>of</strong> y n+l <strong>and</strong> lete (y)n (l) =y n+l − y n (l) be the correspond<strong>in</strong>g forecast error. <strong>The</strong> variance <strong>of</strong> the l-steps-aheadforecast error <strong>of</strong> y n+l for the RCA(1) model with seasonal GARCH errors as given <strong>in</strong> (13)- (15)is:Var[e (y)n (l)] =ω(1 − β 2 )()pP1 − ∑ φ i)(1 − ∑ Φ ii=1i=1l−1∑ β 2j . (22)(1 − β 2 − σb 2) j=0Pro<strong>of</strong>. <strong>The</strong> y t process is second order stationary with autocorrelation ρ k = β k <strong>and</strong> varianceσ 2 ɛ /(1 − β 2 − σ 2 b ). Hence, y t has a valid mov<strong>in</strong>g average representation <strong>of</strong> the form y ∗ t =


Recent Developments <strong>in</strong> SeasonalVolatility Models 9Recent Developments <strong>in</strong> Seasonal Volatility Models39∑ ∞ j=0 βj a t−j ,wherea t is an uncorrelated sequence with variance σa 2 . By equat<strong>in</strong>g the variance<strong>of</strong> y ∗ t to the variance <strong>of</strong> y t we have σɛ 2/(1 − β2 − σb 2)=σ2 a /(1 − β2 ),<strong>and</strong>σa 2 = σɛ 2 (1 − β 2 )/(1 −β 2 − σb 2).Note: When σb 2 = 0, var[e(y) n (l)] <strong>in</strong> <strong>The</strong>orem 4.1 reduces to var[e (y)n (l)] <strong>in</strong> <strong>The</strong>orem 3.1 for theAR model with seasonal GARCH errors.We now have expressions for the variance <strong>of</strong> the l-steps-ahead forecast error <strong>of</strong> y n+l for thepreviously discussed RCA(1)-GARCH(p, q)x(P, Q) s models:RCA(1)-GARCH(0, 1)x(0, 1) sRCA(1)-GARCH(0, 1)x(1, 0) sRCA(1)-GARCH(1, 0)x(1, 0) sVar[e (y)n (l)] = ω(1 − β2 l−1)(1 − β 2 − σb 2) ∑Var[e (y)n (l)] =Var[e (y)n (l)] =β 2jj=0ω(1 − β 2 l−1)(1 − Φ)(1 − β 2 − σb 2) ∑ β 2j ,j=0ω(1 − β 2 l−1)(1 − φ)(1 − Φ)(1 − β 2 − σb 2) ∑ β 2j .j=0<strong>The</strong>orem 4.2. Let Y t =[y t − ( ˆβ + b t )y t−1 ] 2 . Also, let Y n (l) be the l-steps-ahead m<strong>in</strong>imummean square forecast <strong>of</strong> Y n+l <strong>and</strong> let e (Y)n (l) = Y n+l − Y n (l) be the correspond<strong>in</strong>g forecasterror. <strong>The</strong> variance <strong>of</strong> the l-steps-ahead forecast error <strong>of</strong> Y n+l for the RCA(1) model withseasonal GARCH errors as given <strong>in</strong> (13)- (15) is:⎡ ⎤Var[e (Y)n (l)] = σu2 l−1∑ Ψ 2 ω 2j = ⎡ ⎤ [ ]j=0⎣∑∞ p 2 ]Ψ 2 P 2[K⎦j 1 − ∑ φ i[1 (ɛ) − 1] ⎣ l−1∑ Ψ 2 ⎦j (23)j=0− ∑ Φ ij=0i=1i=1where, from (18), K (ɛ) = 1 − (3σ4 b + β4 + 6β 2 σb 2)[1 − (β 2 + σb 2 K (y) − 6(β2 + σb 2))]2 1 − (β 2 + σb 2) .Pro<strong>of</strong>. <strong>The</strong> pro<strong>of</strong> follows from part (b) <strong>of</strong> Lemma 3.2.Note: When σb 2 = 0, K(ɛ) <strong>in</strong> <strong>The</strong>orem 4.2 reduces to K (ɛ) <strong>in</strong> <strong>The</strong>orem 3.2 for the AR model withseasonal GARCH errors.We now have expressions for the variance <strong>of</strong> the l-steps-ahead forecast error for the previouslydiscussed RCA(1)-GARCH(p, q)x(P, Q) s models:RCA(1)-GARCH(0, 1)x(0, 1) sRCA(1)-GARCH(0, 1)x(1, 0) sRCA(1)-GARCH(1, 0)x(1, 0) sVar[e (Y)n (l)] = (K(ɛ) − 1)μ 2 l−1(1 + θ 2 )(1 + Θ 2 )∑ Ψ 2 jj=0Var[e (Y)n (l)] = (K(ɛ) − 1)μ 2 (1 − Φ 2 l−1)1 + θ∑2 Ψ 2 jj=0Var[e (Y)n (l)] = (K(ɛ) − 1)μ 2 (1 − φ 2 l−1)1 + 2φ s Φ +∑Φ 2 Ψ 2 jj=0which are similar to the expressions given <strong>in</strong> Doshi et al. (2011). Here, K (ɛ) is given <strong>in</strong> <strong>The</strong>orem4.2. <strong>and</strong> expressions for K (y) for a conditionally normally distributed ɛ t are given <strong>in</strong> Examples4.1, 4.2, <strong>and</strong> 4.3.


40 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications10 Will-be-set-by-IN-TECH5. RCA models with seasonal SV errorsWe start with Taylor’s (2005) stochastic volatility (SV) model <strong>and</strong> propose its seasonal form,y t =(β + b t )y t−1 + ɛ t (24)ɛ t = Z t e 1 2 h tZ t ∼ N(0, 1) (25)φ(B)Φ(L)h t = ω + v t v t ∼ N(0, σ 2 v ) (26)where ɛ t <strong>and</strong> h t are <strong>in</strong>novations <strong>of</strong> the observed time series y t <strong>and</strong> the unobserved stochasticqvolatility, respectively. Also, φ(B) =1 − ∑ φ i B i Q, Φ(L) =1 − ∑ Φ i L i ,<strong>and</strong>L = B s ,wheresi=1i=1is the seasonal period. We assume that all the zeros <strong>of</strong> the polynomial φ(B)Φ(L) lie outsidethe unit circle; thus, h t as given <strong>in</strong> (26) is stationary. <strong>The</strong> mov<strong>in</strong>g average representation ish t = ω + ∑ ∞ j=0 Ψ jv t−j where {Ψ j } is a sequence <strong>of</strong> constants <strong>and</strong> ∑ ∞ j=0 Ψ2 j< ∞. <strong>The</strong>Ψ j ’s areobta<strong>in</strong>ed from φ(B)Φ(L)Ψ(B) =1whereΨ(B) =1 + ∑ ∞ j=1 Ψ jB j .RCA models with SV <strong>in</strong>novations have been studied <strong>in</strong> Paseka et al. (2010). Here we considerthe seasonal version <strong>of</strong> the SV process <strong>and</strong> we study the moment properties <strong>of</strong> RCA modelswith seasonal SV <strong>in</strong>novations.<strong>The</strong>orem 5.1. Suppose y t is an RCA model with seasonal SV <strong>in</strong>novations as <strong>in</strong> (24)– (26).<strong>The</strong>n, we have the follow<strong>in</strong>g relationship:(i) E(y 2 t )= E(ɛ 2 t )1 − (β 2 + σb 2) ,(ii) E(y 4 t )= 6(σ2 b + β2 )[E(ɛ 2 t )]2 +[1 − (β 2 + σ 2 b )]E(ɛ4 t )1 − (3σ 4 b + β4 + 6β 2 σ 2 b )[1 − (β2 + σ 2 b )] ,(iii) K (y) = 6(σ2 b + β2 )[1 − (β 2 + σb 2)][1 − (β 2 + σb 21 − (3σb 4 + β4 + 6β 2 σb 2) +)]21 − (3σb 4 + β4 + 6β 2 σb 2) K(ɛ) ,(iv) K (ɛ) = 3e σ2 v ∑ ∞ j=0 Ψ2 j{ }{where E(ɛ 2 t )=exp μ ht + 1 2 σ2 h t, E(ɛ 4 t )=3exp 2μ ht + 2σh 2 t}, the mean <strong>of</strong> the h t process isωμ ht=(1 − ∑ q i=1 φ i)(1 − ∑ Q i=1 Φ i) <strong>and</strong> the variance <strong>of</strong> h t is σh 2 t= σv 2 ∑ ∞ j=0 Ψ2 j .Pro<strong>of</strong>. Parts (i) to (iii) are similar to Paseka et al. (2010) for an RCA-non seasonal SV process.Part (iv) follows from the above expressions for E(ɛ 2 t ) <strong>and</strong> E(ɛ4 t ) as follows:K (ɛ) = E(ɛ4 t )[E(ɛ 2 =3e2μ h t +2σh 2 t=t )]2 (e μ 3e σ2 h t = 3e σ2 v ∑ ∞ j=0 Ψ 2 j.h t +1/2σh 2 t ) 2Next, we illustrate applications <strong>of</strong> <strong>The</strong>orem 5.1 with three examples.Example 5.1. RCA with autoregressive [AR(1)] SV processy t =(β + b t )y t−1 + ɛ tɛ t = Z t e 1 2 h t(1 − φB)h t = ω + v t


Recent Developments <strong>in</strong> SeasonalVolatility Models 11Recent Developments <strong>in</strong> Seasonal Volatility Models<strong>The</strong> Ψ-weights are Ψ j = φ j , j ≥ 1. <strong>The</strong>refore, ∑ ∞ j=0 Ψ2 j= 1 + φ 2 + φ 4 + ...= 1 . <strong>The</strong>n, the1 − φ2 kurtosis <strong>of</strong> y t is:K (y) = 6(σ2 b + β2 )[1 − (β 2 + σb 2)][1 − (β 2 + σ 2 {b1 − (3σb 4 + β4 + 6β 2 σb 2) + 3)]2σ 2 }1 − (3σb 4 + β4 + 6β 2 σb 2) exp v1 − φ 2 .Example 5.2. RCA with pure seasonal autoregressive [AR(1) s ]SVprocessy t =(β + b t )y t−1 + ɛ tɛ t = Z t e 1 2 h t(1 − ΦB s )h t = ω + v t<strong>The</strong> Ψ-weights are Ψ j = Φ j , j ≥ 1. <strong>The</strong>refore, ∑ ∞ j=0 Ψ2 j= 1 + Φ 2 + Φ 4 1+ ... =1 − Φ 2 . <strong>The</strong>n,the kurtosis <strong>of</strong> y t is:K (y) = 6(σ2 b + β2 )[1 − (β 2 + σb 2)][1 − (β 2 + σ 2 {1 − (3σb 4 + β4 + 6β 2 σb 2) + 3b )]2σ 2 }1 − (3σb 4 + β4 + 6β 2 σb 2) exp v1 − Φ 2 .Example 5.3. RCA with multiplicative seasonal autoregressive [AR(1)x(1) s ]SVprocessy t =(β + b t )y t−1 + ɛ tɛ t = Z t e 1 2 h t(1 − φB)(1 − ΦB s )h t = ω + v t<strong>The</strong> Ψ-weights are Ψ 1 = φ + Φ, <strong>and</strong>Ψ j =(φ + Φ)Ψ j−1 + φΦΨ j−2 , j ≥ 2. <strong>The</strong>n, the kurtosis<strong>of</strong> y t is:K (y) = 6(σ2 b + β2 )[1 − (β 2 + σb 2)][1 − (β 2 + σb 21 − (3σb 4 + β4 + 6β 2 σb 2) + 3)]21 − (3σb 4 + β4 + 6β 2 σb 2) eσ2 h twhere σh 2 (1 + φ s )σv2t=(1 − φ 2 )(1 − Φ 2 )(1 − Φφ s ) .Recently, Gong & Thavaneswaran (2009) discussed the filter<strong>in</strong>g <strong>of</strong> SV models. <strong>The</strong> prediction<strong>of</strong> discrete SV models can be obta<strong>in</strong>ed by us<strong>in</strong>g the recursive method proposed <strong>in</strong>Gong & Thavaneswaran (2009).6. Option pric<strong>in</strong>g with seasonal volatilityOption pric<strong>in</strong>g based on the Black-Scholes model is widely used <strong>in</strong> the f<strong>in</strong>ancial community.<strong>The</strong> Black-Scholes formula is used for the pric<strong>in</strong>g <strong>of</strong> European-style options. <strong>The</strong> modelhas traditionally assumed that the volatility <strong>of</strong> returns is constant. However, severalstudies have shown that asset returns exhibit variances that change over time. Duan (1995)proposes an option pric<strong>in</strong>g model for an asset with returns follow<strong>in</strong>g a GARCH process.Badescu & Kulpeger (2008); Elliot et al. (2006); Heston & N<strong>and</strong>i (2000) <strong>and</strong> others derivedclosed form option pric<strong>in</strong>g formulas for different models which are assumed to follow aGARCH volatility process. Most recently, Gong et al. (2010) derive an expression for the callprice as an expectation with respect to r<strong>and</strong>om GARCH volatility. <strong>The</strong> model is then evaluated41


42 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications12 Will-be-set-by-IN-TECH<strong>in</strong> terms <strong>of</strong> the moments <strong>of</strong> the volatility process. <strong>The</strong>ir results <strong>in</strong>dicate that the suggestedmodel outperforms the classic Black-Scholes formula. Here we extend Gong et al. (2010) <strong>and</strong>propose an option pric<strong>in</strong>g model with seasonal GARCH volatility as follows:dS t = rS t dt + σ t S t dW t (27)( ) [ ( )]StSty t = log − E log = σ t Z tS t−1 S t−1(28)θ(B)Θ(L)σ 2 t = ω + α(B)y 2 t (29)where S t is the price <strong>of</strong> the stock, r is the risk-free <strong>in</strong>terest rate, {W t } is a st<strong>and</strong>ard Brownianmotion, σ t is the time-vary<strong>in</strong>g seasonal volatility process, {Z t } is a sequence <strong>of</strong> i.i.d. r<strong>and</strong>omvariables with zero mean <strong>and</strong> unit variance <strong>and</strong> α(B), θ(B) <strong>and</strong> Θ(L) have been def<strong>in</strong>ed <strong>in</strong>(4).<strong>The</strong> price <strong>of</strong> a call option can be calculated us<strong>in</strong>g the option pric<strong>in</strong>g formula given <strong>in</strong>Gong et al. (2010). <strong>The</strong> call price is derived as a first conditional moment <strong>of</strong> a truncatedlognormal distribution under the mart<strong>in</strong>gale measure, <strong>and</strong> it is based on estimates <strong>of</strong> themoments <strong>of</strong> the GARCH process. <strong>The</strong> call price based on the Black-Scholes model withseasonal GARCH volatility is given by:C(S, T) =S(f [E(σ 2 t )] + 1 2 f ′′ [E(σ 2 t )]( 13 κ(y) − 1))E 2 (σt 2 )− Ke(g[E(σ −rT t 2 )] + 1 ( ) )2 g′′ [E(σt 2 1)]3 κ(y) − 1 E 2 (σt 2 ) , (30)where f <strong>and</strong> g are twice differentiable functions, S is the <strong>in</strong>itial value <strong>of</strong> S t , K is the strike price,T is the expiry date, σ t is a stationary process with f<strong>in</strong>ite fourth moment, <strong>and</strong> κ (y) = E(y4 t ) .[E(y 2 t )]2Also, f [E(σt 2)], g[E(σ2 t )], f ′′ [E(σt 2)],<strong>and</strong>g′′ [E(σt 2 )] are given by:⎛⎞f [E(σt 2 )] = N(d) =N ⎝ log(S/K)+rT + 1 2 E(σ2 t√) ⎠ ,E(σt 2)[ ⎛f ′′ [E(σt 2)] = √ 1 − 2π()g[E(σt 2 )] = N d −√E(σ t 2) ⎝ E(σ2 t ) − 2(log(S/K)+rT)4E(σ 2 t ) √E(σ 2 t )⎛⎞= N ⎝ log(S/K)+rT − 1 2 E(σ2 t√) ⎠ ,E(σt 2)⎞⎠( )[E(σ 2t )] 2 − 4(log(S/K)+rT) 28[E(σt 2)]2 ⎛⎞+ ⎝ 6(log(S/K)+rT) − E(σ2 t )] {}√ ⎠ × exp − (2(log(S/K)+rT)+E(σ2 t ))28[E(σt 2)]2 E(σt 2)8E(σt 2) ,


Recent Developments <strong>in</strong> SeasonalVolatility Models 13Recent Developments <strong>in</strong> Seasonal Volatility Models43g ′′ [E(σt 2)] = √ 1 [ ⎛ ⎞⎝ E(σ2 t )+2(log(S/K)+rT)√⎠2π 4E(σt 2) E(σt 2)⎛⎞+ ⎝ 6(log(S/K)+rT)+E(σ2 √ t ) ⎠8[E(σt 2)]2 E(σt 2)( )[E(σ 2t )] 2 − 4(log(S/K)+rT) 2[E(σt 2)]2 ] {exp − (2(log(S/K)+rT) − }E(σ2 t ))28E(σt 2) ,where N denotes the st<strong>and</strong>ard normal CDF, <strong>and</strong> under the option pric<strong>in</strong>g model with seasonalGARCH volatility,E(σ 2 t )=κ (y) =ω() ,pP1 − ∑ φ i)(1 − ∑ Φ ii=1i=13∞ .3 − 2 ∑ Ψ 2 jj=17. Conclud<strong>in</strong>g remarksIn this chapter we propose various classes <strong>of</strong> seasonal volatility models. We consider timeseries processes such as AR <strong>and</strong> RCA with multiplicative seasonal GARCH errors <strong>and</strong> SVerrors. <strong>The</strong> multiplicative seasonal volatility models are suitable for time series whereautocorrelation exists at seasonal <strong>and</strong> at adjacent non-seasonal lags. <strong>The</strong> models <strong>in</strong>troducedhere extend <strong>and</strong> complement the exist<strong>in</strong>g volatility models <strong>in</strong> the literature to seasonalvolatility models by <strong>in</strong>troduc<strong>in</strong>g more general structures.It is well-known that f<strong>in</strong>ancial time series exhibit excess kurtosis. In this chapter we derivethe kurtosis for different seasonal volatility models <strong>in</strong> terms <strong>of</strong> model parameters. We alsoderive the closed-from expression for the variance <strong>of</strong> the l-steps ahead forecast error <strong>of</strong> i)y n+l <strong>in</strong> terms <strong>of</strong> ψ-weights <strong>and</strong> model parameters, <strong>and</strong> <strong>of</strong> ii) squared series Y n+l <strong>in</strong> terms<strong>of</strong> Ψ-weights, model parameters <strong>and</strong> the kurtosis <strong>of</strong> ɛ t . <strong>The</strong> results are a generalization <strong>of</strong>exist<strong>in</strong>g results for non-seasonal volatility processes. We provide examples for all the differentclasses <strong>of</strong> models considered <strong>and</strong> discussed them <strong>in</strong> some detail (i.e. AR(1)-GARCH(p, q) ×(P, Q) s , RCA(1)-GARCH(p, q) × (P, Q) s <strong>and</strong> RCA(1)-seasonal SV).<strong>The</strong> results are primarily oriented to f<strong>in</strong>ancial time series applications. F<strong>in</strong>ancial time series<strong>of</strong>ten meet the large dataset dem<strong>and</strong>s <strong>of</strong> the volatility models studied here. Also, f<strong>in</strong>ancial datadynamics <strong>in</strong> higher order moments are <strong>of</strong> <strong>in</strong>terest to many market participants. Specifically,we consider the Black-Scholes model with seasonal GARCH volatility <strong>and</strong> show that themoments <strong>of</strong> the seasonal volatility process can be used to evaluate the call price for Europeanoptions.8. ReferencesBadescu, A. & Kulperger, R. (2008). GARCH option pric<strong>in</strong>g: A semiparametric approach.Insurance, <strong>Mathematics</strong> & Economics, Vol. 43, No. 1, 69 – 84, ISSN 0167-6687


44 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications14 Will-be-set-by-IN-TECHBaillie, R. & Bollerslev, T. (1990). Intra-day <strong>and</strong> <strong>in</strong>ter-market volatility <strong>in</strong> foreign exchangerates. Review <strong>of</strong> Economic Studies, Vol. 58, No. 3, 565 – 585, ISSN 0034-6527Bollerslev, T. (1986). Generalized autoregressive conditional heteroscedasticity. Journal <strong>of</strong>Econometrics, Vol. 31, 307 – 327, ISSN 0304-4076Bollerslev, T. & Ghysels, E. (1996). Periodic autoregressive conditional heteroscedasticity.Journal <strong>of</strong> Bus<strong>in</strong>ess <strong>and</strong> Economic Statistics, Vol. 14, No. 2, 139 – 151, ISSN: 0735-0015Doshi, A.; Frank, J.; Thavaneswaran, A. (2011). Seasonal volatility models. Journal <strong>of</strong> Statistical<strong>The</strong>ory <strong>and</strong> Applications, Vol. 10, No. 1, 1–10, ISSN 1538-7887Duan, J. (1995). <strong>The</strong> GARCH option ric<strong>in</strong>g model. Mathematical F<strong>in</strong>ance, Vol. 5, 13–32, ISSN0960-1627Elliot, R.; Siu, T.; Chan, L. (2006). Option pric<strong>in</strong>g for GARCH models with Markov switch<strong>in</strong>g.International Journal <strong>of</strong> <strong>The</strong>oretical <strong>and</strong> Applied F<strong>in</strong>ance, Vol. 9, No. 6, 825–841, ISSN0219-0249Engle, R. (1982). Autoregressive conditional heteroskedasticity with estimates <strong>of</strong> the variance<strong>of</strong> U.K. <strong>in</strong>flation. Econometrica, Vol. 50, 987–1008, ISSN 0012-9682Frank, J. & Garcia, P. (2009). Time-vary<strong>in</strong>g risk premium: further evidence <strong>in</strong> agriculturalfutures markets. Applied Economics, Vol. 41, No. 6, 715 – 725, ISSN 0003-6846Franses, P. & Paap, R. (2000). Modell<strong>in</strong>g day-<strong>of</strong>-the-week seasonality <strong>in</strong> the S&P 500 <strong>in</strong>dex.Applied F<strong>in</strong>ancial Economics, Vol. 10, No. 5, 483 – 488, ISSN 0960-3107Ghahramani, M. & Thavaneswaran, A. (2007). Identification <strong>of</strong> ARMA models with GARCHerrors. <strong>The</strong> Mathematical Scientist, Vol. 32, No. 1, 60 – 69, ISSN 0312-3685Ghysels, E. & Osborn, D. (2001). <strong>The</strong> econometric analysis <strong>of</strong> seasonal time series, CambridgeUniversity Press, ISBN 0-521-56588-X, United K<strong>in</strong>gdom.Gong, H. & Thavaneswaran, A. (2009). Recursive estimation for cont<strong>in</strong>uous time stochasticvolatility models. Applied <strong>Mathematics</strong> Letters, Vol. 22, No. 11, 1770 – 1774, ISSN0893-9659Gong, H.; Thavaneswaran, A.; S<strong>in</strong>gh, J. (2010). A Black-Scholes model with GARCH volatility.<strong>The</strong> Mathematical Scientist, Vol. 35, No. 1, 37–42, ISSN 0312-3685Heston, S. & N<strong>and</strong>i, S. (2000). A closed-form GARCH option valuation model. <strong>The</strong> Review <strong>of</strong>F<strong>in</strong>ancial Studies, Vol. 13, No. 3, 585 – 625, ISSN 0893-9454Nicholls, D. & Qu<strong>in</strong>n, B. (1982). R<strong>and</strong>om coefficient autoregressive models: An <strong>in</strong>troduction.Lecture Notes <strong>in</strong> Statistics, Vol. 11, Spr<strong>in</strong>ger, ISSN 0930-0325, New York.Paseka, A.; Appadoo, S.; Thavaneswaran, A. (2010). R<strong>and</strong>om coefficient autoregressive (RCA)models with nonl<strong>in</strong>ear stochastic volatility <strong>in</strong>novations. Journal <strong>of</strong> Applied StatisticalScience, Vol. 17, No. 3, 331–349, ISSN 1067-5817Taylor, S. (2005). Asset price dynamics, volatility, <strong>and</strong> prediction, Pr<strong>in</strong>ceton University Press, ISBN0-691-11537-0, New Jersey.Thavaneswaran, A. & Ghahramani, M. (2008). Volatility forecasts with GARCH errors <strong>and</strong>applications. Journal <strong>of</strong> Statistical <strong>The</strong>ory <strong>and</strong> Applications, Vol. 1, No. 1, 69 – 80, ISSN1538-7887Thavaneswaran, A.; Appadoo, S.; Ghahramani, M. (2009). RCA models with GARCH<strong>in</strong>novations. Applied <strong>Mathematics</strong> Letters, Vol. 22, 110–114, ISSN 0893-9659Thavaneswaran, A.; Appadoo, S.; Peiris, S. (2005a). Forecast<strong>in</strong>g volatility. Statistics <strong>and</strong>Probability Letters, Vol. 75, No. 1, 1–10, ISSN: 0167-7152Thavaneswaran, A.; Appadoo, S.; Samanta, M. (2005b). R<strong>and</strong>om coefficient GARCH Models.Mathematical <strong>and</strong> Computer Modell<strong>in</strong>g, Vol. 41, No. 1–7, 723–733, ISSN 0895-7177


Part 2Recent Econometric Applications


<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>gPrograms on the Labor Market Transitions <strong>of</strong>Disadvantaged Men40Lucie Gilbert 1 , Thierry Kamionka 2 <strong>and</strong> Guy Lacroix 31 Human Resources Development Canada2 CREST, CNRS3 CIRPÉE, CIRANO, IZA, Laval University1,3 Canada2 France1. Introduction<strong>The</strong> impact <strong>of</strong> government-sponsored tra<strong>in</strong><strong>in</strong>g programs has been extensively studied <strong>in</strong>the past couple <strong>of</strong> decades. 1 In many countries, such programs have become an <strong>in</strong>tegralpart <strong>of</strong> public policies aim<strong>in</strong>g at enhanc<strong>in</strong>g self-sufficiency among vulnerable groups. Inmost cases program costs have escalated as they have become more comprehensive <strong>and</strong>more systematically used. Not surpris<strong>in</strong>gly, policy makers have shown renewed <strong>in</strong>terest <strong>in</strong>obta<strong>in</strong><strong>in</strong>g accurate <strong>and</strong> reliable estimates <strong>of</strong> their efficacy.<strong>The</strong> discussions surround<strong>in</strong>g the efficacy or desirability <strong>of</strong> tra<strong>in</strong><strong>in</strong>g programs rest on complexmethodological issues. <strong>The</strong> ma<strong>in</strong> concern lies with proper treatment <strong>of</strong> an <strong>in</strong>dividual’sdecision to participate <strong>in</strong> such programs. Severe biases may arise if unobserved <strong>in</strong>dividualcharacteristics that affect the decision to participate are somehow related to the unobservablesthat affect outcomes on the labour market. Two approaches have been proposed <strong>in</strong>the evaluation literature to address the so-called “self-selection” issue. <strong>The</strong> first is the“experimental approach”, based on r<strong>and</strong>om assignment <strong>of</strong> applicants <strong>in</strong>to treatment orcontrol groups. <strong>The</strong> second is the “non-experimental”, or “econometric approach”, <strong>and</strong> relieson non-r<strong>and</strong>om samples <strong>of</strong> participants <strong>and</strong> non-participants. Each approach tackles theself-selection issue from a different angle, but the relative merit <strong>of</strong> each is still the subject <strong>of</strong>debate [see Heckman & Smith (1995), Burtless (1995), Ham & LaLonde (1996), Keane (2010),Leamer (2010)].Most would argue that the “experimental” approach is best suited to elim<strong>in</strong>ate self-selectionbiases <strong>and</strong> provide adequate mean program impacts, however measured. Yet, recently thisview has been challenged by Ham & LaLonde (1996) <strong>in</strong> their important paper. 2 In essencethey argue that r<strong>and</strong>om assignment between control <strong>and</strong> experimental groups provides an1 See Heckman et al. (1999) for a detailed survey.2 A number <strong>of</strong> papers have found evidence <strong>of</strong> biases <strong>in</strong> r<strong>and</strong>omized field experiments. See Card &Hyslop (2005), Card & Hyslop (2009), Brouillette & Lacroix (2010), Kamionka & Lacroix (2008), Créponet al. (2011).


48 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications2 Will-be-set-by-IN-TECHadequate short-term mean program impact. On the other h<strong>and</strong>, the treatment <strong>and</strong> controlsexperienc<strong>in</strong>g subsequent spells <strong>of</strong> employment <strong>and</strong> unemployment are most likely notr<strong>and</strong>om subsets <strong>of</strong> the <strong>in</strong>itial groups because the sort<strong>in</strong>g process is very different for the two.In other words, r<strong>and</strong>om assignment does not guarantee that long-term mean program impactsare void <strong>of</strong> any systematic biases.In most countries, experimental evaluation <strong>of</strong> tra<strong>in</strong><strong>in</strong>g programs is impracticable due to alack <strong>of</strong> appropriate data. Analysts must rely on multi-state transition models. An additionaldifficulty <strong>in</strong> us<strong>in</strong>g these data is that program participation must be modeled explicitly. Manyrecent papers have nevertheless managed to successfully model complex transition patternsus<strong>in</strong>g such data (Gritz (1993), Bonnal et al. (1997), Mealli et al. (1996), Brouillette & Lacroix(2011), Fougère et al. (2010), Blasco, Crépon & Kamionka (2009)). Most papers are limited tothree separate states <strong>of</strong> the labour market: employment, unemployment (non-employment)<strong>and</strong> tra<strong>in</strong><strong>in</strong>g. 3 In many cases data limitations do not allow identification <strong>of</strong> any morestates. In other cases, analysts purposely focus on few states to keep the statistical modeltractable. Indeed, when the data is drawn from stock samples, as is <strong>of</strong>ten the case whenus<strong>in</strong>g adm<strong>in</strong>istrative data, the statistical model must account for so-called “<strong>in</strong>itial conditions”problems. This usually adds considerable complexity to an already <strong>in</strong>volved statisticalmodel. 4 On the other h<strong>and</strong>, many have questioned the appropriateness <strong>of</strong> focus<strong>in</strong>g on fewlabour market states (Heckman & Fl<strong>in</strong>n (1983), Jones & Riddell (1999)).This chapter <strong>in</strong>vestigates the impact <strong>of</strong> government tra<strong>in</strong><strong>in</strong>g programs aimed at poorlyeducated Canadian male welfare recipients. It should be stressed at the outset that <strong>in</strong> Canada,as <strong>in</strong> many European countries, the welfare system aims at support<strong>in</strong>g <strong>in</strong>dividuals without<strong>in</strong>come <strong>and</strong> who are not entitled to any other social security benefits, irrespective <strong>of</strong> age. 5As such, it acts as a safety net for unemployed workers who do not qualify for benefits,or who have exhausted their unemployment benefits. Many programs are available toassist these long term unemployed <strong>and</strong> those with few skills <strong>in</strong>crease their employability.Underst<strong>and</strong>ably, a considerable proportion <strong>of</strong> program resources has been targeted towardsthe youths <strong>in</strong> the past decade. Yet, many have questioned the ability <strong>of</strong> traditional programsto address the problem [OECD, 1998]. <strong>The</strong> aim <strong>of</strong> this chapter is precisely to <strong>in</strong>vestigate theimpact <strong>of</strong> these programs <strong>in</strong> enhanc<strong>in</strong>g the self-sufficiency <strong>of</strong> young males welfare claimants,a particular disadvantaged group (see Beaudry & Green (2000)).<strong>The</strong> empirical strategy is similar to that used by Gritz (1993), Bonnal et al. (1997) <strong>and</strong>Brouillette & Lacroix (2011) <strong>in</strong> that we explicitly account for selectivity <strong>in</strong>to the tra<strong>in</strong><strong>in</strong>gprograms. It relies on a rich dataset that tracks the transitions <strong>of</strong> a large number <strong>of</strong> <strong>in</strong>dividualson a weekly basis across seven different states <strong>of</strong> the labour market. <strong>The</strong>se states <strong>in</strong>cludeemployment, unemployment, welfare, out <strong>of</strong> the labour force (OLF), two separate welfaretra<strong>in</strong><strong>in</strong>g programs, <strong>and</strong> unemployment tra<strong>in</strong><strong>in</strong>g programs. In all, as many as 24 differenttransitions are allowed <strong>in</strong> the model. <strong>The</strong> sample is drawn from the population <strong>of</strong> welfare3 One notable exception is Bonnal et al. (1997) who consider as many as 6 different differentstates: permanent employment, temporary employment, public policy employment (tra<strong>in</strong><strong>in</strong>g),unemployment, out-<strong>of</strong>-labour-force (non-employment), <strong>and</strong> an absorb<strong>in</strong>g state (attrition).4 Two biases are likely to result from stock samples: (1) length-bias; (2) <strong>in</strong>flow-rate bias. <strong>The</strong> former mayarise because lengthy spells are more likely to be ongo<strong>in</strong>g at the time the sample is chosen. <strong>The</strong> latter isrelated to the fact that the probability <strong>of</strong> be<strong>in</strong>g sampled is related to the probability <strong>of</strong> start<strong>in</strong>g a freshspell at time the sample is chosen. See Gouriéroux & Monfort (1992) <strong>and</strong> Van den Berg et al. (1994) fora detailed analysis.5 Individuals must be aged over 18 to qualify for benefits, although s<strong>in</strong>gle parents less than 18 still qualify.


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 349recipients that experienced a spell at any time between 1987 <strong>and</strong> 1993 <strong>in</strong> the prov<strong>in</strong>ce <strong>of</strong>Québec, Canada. To be <strong>in</strong>cluded <strong>in</strong> the sample, <strong>in</strong>dividuals had to be aged 18 or 19 at anytime dur<strong>in</strong>g that period <strong>and</strong> to have less than a high-school degree. Sample stratification isused to avoid over-parameterization <strong>of</strong> the statistical model that would result if too manyexogenous variables had to be controlled for.By merg<strong>in</strong>g various adm<strong>in</strong>istrative data files we can recreate complete <strong>in</strong>dividuals’ historieson the labour market back to age 16, the legal school-leav<strong>in</strong>g age <strong>in</strong> Canada. Consequently,each <strong>in</strong>dividual <strong>in</strong> our sample is necessarily observed <strong>in</strong> the OLF state at the beg<strong>in</strong>n<strong>in</strong>g <strong>of</strong>his history. This sampl<strong>in</strong>g scheme thus removes the necessity to control for stock samplebiases <strong>and</strong> has the additional benefit <strong>of</strong> provid<strong>in</strong>g rich transition patterns over a relativelylong sample frame.<strong>The</strong> econometric model is built on cont<strong>in</strong>uous labour market transitions processes <strong>and</strong>allows entry rates <strong>in</strong>to each state to depend on observed <strong>and</strong> unobserved heterogeneitycomponents. Heterogeneity terms can be dest<strong>in</strong>ation-specific, orig<strong>in</strong>-specific or both. In allcases, correlation across heterogeneity terms is allowed. We further <strong>in</strong>vestigate the sensitivity<strong>of</strong> the parameter estimates to various distributions <strong>of</strong> the heterogeneity components. Whenparametric distribution functions are used, the model is estimated by Simulated MaximumLikelihood (SML).<strong>The</strong> rema<strong>in</strong>der <strong>of</strong> the chapter is organized as follows. Section 2 provides a detailed description<strong>of</strong> the data. Section 3 discusses the econometric model <strong>and</strong> the various statistical assumptionregard<strong>in</strong>g the distributions <strong>of</strong> the heterogeneity terms. Section 4 reports our empiricalf<strong>in</strong>d<strong>in</strong>gs. Section 5 concludes the chapter.2. Data description<strong>The</strong> basic data used for this study are drawn from the caseload records <strong>of</strong> Québec’s M<strong>in</strong>istèrede la Solidarité sociale. <strong>The</strong> files conta<strong>in</strong> <strong>in</strong>formation on all <strong>in</strong>dividuals who have receivedwelfare benefits at some time between January 1987 <strong>and</strong> December 1993. In particular, thestart dates <strong>and</strong> end dates <strong>of</strong> each welfare <strong>and</strong> welfare tra<strong>in</strong><strong>in</strong>g spells are recorded <strong>in</strong> the files.<strong>The</strong> welfare program conta<strong>in</strong>s special provisions for those who are <strong>in</strong>disposed for work due tomental or physical impediments. <strong>The</strong>se <strong>in</strong>dividuals are not <strong>in</strong>cluded <strong>in</strong> the sample. Thus thef<strong>in</strong>al sample comprises only <strong>in</strong>dividuals who have no h<strong>and</strong>icap or only a m<strong>in</strong>or, <strong>in</strong>termediate,or temporary physical h<strong>and</strong>icap. Furthermore, they are fit to work.<strong>The</strong> welfare adm<strong>in</strong>istrative files conta<strong>in</strong> no <strong>in</strong>formation on employment or unemploymentspells. Our sample was thus l<strong>in</strong>ked to the Status Vector files (SV) <strong>and</strong> the Record <strong>of</strong>Employment (ROE) files, both under the aegis <strong>of</strong> Human Resources Development Canada.<strong>The</strong>se files conta<strong>in</strong> very detailed weekly <strong>in</strong>formation on <strong>in</strong>sured unemployment spells <strong>and</strong>employment spells, respectively. <strong>The</strong> start dates <strong>and</strong> end dates <strong>of</strong> each spell are recorded<strong>in</strong> these files. Similar <strong>in</strong>formation is available with respect to tra<strong>in</strong><strong>in</strong>g spells adm<strong>in</strong>isteredunder the Unemployment Insurance (UI) program. Merg<strong>in</strong>g all three adm<strong>in</strong>istrative filesallows us to def<strong>in</strong>e seven different states on the labour market. Aside from the welfare,


50 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications4 Will-be-set-by-IN-TECHunemployment <strong>and</strong> employment states, we can identify two separate welfare tra<strong>in</strong><strong>in</strong>g states<strong>and</strong> one unemployment tra<strong>in</strong><strong>in</strong>g state. 6<strong>The</strong> focus <strong>of</strong> this chapter is on poorly educated young men. Thus to be <strong>in</strong>cluded <strong>in</strong> the sample,an <strong>in</strong>dividual had to be either 18 or 19 years <strong>of</strong> age at any time between 1987 <strong>and</strong> 1993 <strong>and</strong> havecompleted less than 11 years <strong>of</strong> school<strong>in</strong>g over the sample period. A high-school degree <strong>in</strong>Québec usually entails at least 12 years <strong>of</strong> school<strong>in</strong>g. In pr<strong>in</strong>ciple, then, none <strong>of</strong> the <strong>in</strong>dividuals<strong>in</strong> our sample has earned a high-school diploma. With these selection criteria the f<strong>in</strong>al sampleconta<strong>in</strong>s 3068 <strong>in</strong>dividuals.<strong>The</strong> upper panel <strong>of</strong> Table 1 provides summary statistics for <strong>in</strong>dividuals who have notparticipated <strong>in</strong> a tra<strong>in</strong><strong>in</strong>g program. <strong>The</strong> lower panel presents similar statistics for programparticipants. In the latter case, the mean durations <strong>in</strong> either employment, unemployment orwelfare are calculated both before <strong>and</strong> after tra<strong>in</strong><strong>in</strong>g. An exam<strong>in</strong>ation <strong>of</strong> the table revealsthat the two groups are very similar <strong>in</strong> terms <strong>of</strong> their observable characteristics; <strong>The</strong>y bothhave the same average age <strong>and</strong> nearly identical school<strong>in</strong>g levels. Yet, there are significantdifferences <strong>in</strong> their respective labour market experiences. For <strong>in</strong>stance, non-tra<strong>in</strong>ees havelonger spells <strong>in</strong> each <strong>of</strong> the three states reported <strong>in</strong> the table. On the whole, the proportion <strong>of</strong>time non-tra<strong>in</strong>ees spend employed is slightly larger than that <strong>of</strong> tra<strong>in</strong>ees prior to tra<strong>in</strong><strong>in</strong>g. Onthe other h<strong>and</strong>, once they have had tra<strong>in</strong><strong>in</strong>g, the proportion <strong>of</strong> time tra<strong>in</strong>ees spend employedbecomes larger than that <strong>of</strong> non-tra<strong>in</strong>ees. This <strong>in</strong>crease stems from the fact that the averageemployment duration decreases proportionately less that the average duration <strong>of</strong> welfare <strong>and</strong>unemployment spells. Taken at face value, this would suggest tra<strong>in</strong><strong>in</strong>g programs benefitsomewhat to welfare recipients.Recall that only <strong>in</strong>dividuals who experienced a welfare spell between 1987 <strong>and</strong> 1993 <strong>and</strong> whowere aged 18 or 19 dur<strong>in</strong>g that period are <strong>in</strong>cluded <strong>in</strong> the sample. Those who are 18 or 19 years<strong>of</strong> age <strong>in</strong> January 1987 may have already been on the labour market for 2–3 years at most. Inorder to recreate their complete labour market histories as <strong>of</strong> the age <strong>of</strong> 16, it is necessary <strong>in</strong>some cases to go back as early as January 1984. 7 <strong>The</strong> start date <strong>and</strong> end date <strong>of</strong> each spell isused to create <strong>in</strong>dividual histories on the labour market. Overlaps between states are frequent<strong>and</strong> are not necessarily the result <strong>of</strong> cod<strong>in</strong>g errors. It may well be, for example, that a welfarespell <strong>and</strong> a work spell overlap. Program designs do not forbid this. In pr<strong>in</strong>ciple, such overlapscould be redef<strong>in</strong>ed as a separate state. Given the number <strong>of</strong> possible states, it is simply not6 <strong>The</strong> welfare files conta<strong>in</strong> <strong>in</strong>formation dat<strong>in</strong>g back to 1979 <strong>and</strong> end<strong>in</strong>g <strong>in</strong> December 1993. <strong>The</strong> SV filesconta<strong>in</strong>s <strong>in</strong>formation beg<strong>in</strong>n<strong>in</strong>g <strong>in</strong> January 1987 <strong>and</strong> end<strong>in</strong>g <strong>in</strong> December 1996. F<strong>in</strong>ally, <strong>The</strong> ROEfiles conta<strong>in</strong> <strong>in</strong>formation rang<strong>in</strong>g from January 1975 to December 1996. <strong>The</strong> analysis focuses on the1987–1993 period due to data limitations.7 Data concern<strong>in</strong>g unemployment spells are available only as <strong>of</strong> January 1987. Consequently, a smallproportion <strong>of</strong> unemployment spells occurr<strong>in</strong>g prior to 1987 may be wrongly coded as out <strong>of</strong> the labourforce (OLF). Two factors lead us to believe that the proportion <strong>of</strong> such spells is likely <strong>in</strong>significant. First,the large majority <strong>of</strong> <strong>in</strong>dividuals who were 18 or 19 years <strong>of</strong> age <strong>in</strong> the years 1990 <strong>and</strong> beyond where<strong>in</strong> the OLF, the employment or the welfare states between 16 <strong>and</strong> 19. Second, <strong>of</strong> those <strong>in</strong>dividuals, themajority who had an employment spell would not have qualified for UI benefits given the eligibilityrules that prevailed between 1984 <strong>and</strong> 1987.A similar problem arises with respect to employment spells. Indeed, spells that were ongo<strong>in</strong>g <strong>in</strong>December 1993 will not show up <strong>in</strong> the ROE files until they are term<strong>in</strong>ated. To avoid misclassify<strong>in</strong>gthese spells as OLF, the ROE files are searched as late as December 1996. Given the average length<strong>of</strong> employment spells reported <strong>in</strong> Table 1, it is very unlikely that many employment spells that wereongo<strong>in</strong>g <strong>in</strong> December 1993 will still be ongo<strong>in</strong>g as late as December 1996, <strong>and</strong> thus wrongly classifiedas OLF.


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 551Mean Std. dev. Mean Std. dev.Individual without tra<strong>in</strong><strong>in</strong>gAge when enter<strong>in</strong>g the sample 19.92 1.84Education 9.84 1.03Duration <strong>of</strong> employment episodes (weeks) † 26.15 30.47Duration <strong>of</strong> welfare episodes (weeks) † 35.63 34.43Duration <strong>of</strong> unemployment episodes (weeks) † 39.90 11.99Duration <strong>of</strong> OLF episodes (weeks) † 42.99 50.95Proportion <strong>of</strong> time employed (weeks) ‡ 0.18Number <strong>of</strong> observations 1165Individual with tra<strong>in</strong><strong>in</strong>gAge when enter<strong>in</strong>g the sample 19.77 (1.95)Education 9.72 (1.03)Before tra<strong>in</strong><strong>in</strong>g After tra<strong>in</strong><strong>in</strong>gDuration <strong>of</strong> employment episodes (weeks) † 24.26 37.13 17.44 18.25Duration <strong>of</strong> welfare episodes (weeks) † 54.90 54.86 35.14 51.09Duration <strong>of</strong> unemployment episodes (weeks) † 41.25 14.41 35.73 16.83Duration <strong>of</strong> OLF episodes (weeks) † 30.78 38.86 18.66 21.16Proportion <strong>of</strong> time employed (weeks) ‡ 0.17 0.16Number <strong>of</strong> observations 1903Table 1. Sample Characteristics† Calculated from non censored episodes.‡ Calculated from mean duration <strong>in</strong> employment, unemployment, welfare <strong>and</strong> OLF.reasonable to allow these overlaps <strong>in</strong> the analysis. It was decided that, as a rule, start<strong>in</strong>g dateswould have precedence over ongo<strong>in</strong>g spells. Thus an ongo<strong>in</strong>g spell with known end date istruncated whenever a new state starts prior to the end date. 8<strong>The</strong> 3 068 <strong>in</strong>dividuals <strong>in</strong> our sample experienced as many as 31 422 spells over the sampleperiod. Table 2 presents all the transitions that occurred at any given po<strong>in</strong>t <strong>in</strong> the sampleperiod. <strong>The</strong> table identifies seven separate states on the labour market. Welfare Tra<strong>in</strong><strong>in</strong>g<strong>in</strong>cludes various job search assistance programs as well as skill enhanc<strong>in</strong>g programs aimedat welfare recipients. <strong>The</strong> Job-Reentry Program (JRP) is an on-the-job tra<strong>in</strong><strong>in</strong>g program alsoaimed at welfare recipients. Under this program, participants do not receive benefits but a(subsidized) salary from a regular employer. 9 JRP is treated separately because contrary toother programs most participants qualify for unemployment benefits upon completion. UIis a state <strong>in</strong> which <strong>in</strong>dividuals receive unemployment benefits. Individuals that do not work<strong>and</strong> that do not qualify for benefits are treated as out <strong>of</strong> the labour force (OLF) for the purpose<strong>of</strong> this study. It must thus be kept <strong>in</strong> m<strong>in</strong>d that UI is not necessarily ak<strong>in</strong> to unemployment <strong>in</strong>the usual sense. UI Tra<strong>in</strong><strong>in</strong>g comprises a series <strong>of</strong> tra<strong>in</strong><strong>in</strong>g programs aimed at UI claimants.<strong>The</strong> OLF state is the complement <strong>of</strong> all other states. It <strong>in</strong>cludes full-time students, non-entitledunemployed <strong>in</strong>dividuals <strong>and</strong> <strong>in</strong>dividuals that are truly out <strong>of</strong> the labour force.Table 2 reveals <strong>in</strong>terest<strong>in</strong>g dynamics on the labour market. For <strong>in</strong>stance, the majority <strong>of</strong>welfare spells end either <strong>in</strong> employment, <strong>in</strong> welfare tra<strong>in</strong><strong>in</strong>g or OLF. Likewise, welfare tra<strong>in</strong><strong>in</strong>gspells end either <strong>in</strong> welfare, <strong>in</strong> employment or <strong>in</strong> OLF. Interest<strong>in</strong>gly, most JRP participantsenter regular employment upon completion <strong>of</strong> their program. Very few enter UI even though8 Prelim<strong>in</strong>ary analysis was also conducted giv<strong>in</strong>g the end date precedence over the start date <strong>of</strong> a newspell. <strong>The</strong> result<strong>in</strong>g transitions matrices <strong>and</strong> average durations are very robust to this strategy.9 Non-pr<strong>of</strong>it organizations have to pay a symbolic 1$ per work<strong>in</strong>g day. <strong>The</strong> participants receive regularbenefits.


52 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications6 Will-be-set-by-IN-TECHDest<strong>in</strong>ation Welfare Welfare JRP U.I. U.I. Employment OLFOrig<strong>in</strong> Tra<strong>in</strong><strong>in</strong>g Tra<strong>in</strong><strong>in</strong>gWelfare 0 1809 140 88 0 1851 1134Welfare Tra<strong>in</strong><strong>in</strong>g 432 0 67 6 0 438 306JRP 21 4 0 7 0 192 29U.I. 374 38 2 292 111 1380 1404U.I. Tra<strong>in</strong><strong>in</strong>g 2 1 0 114 0 16 2Employment 1002 229 35 2918 41 2004 4662OLF 2614 235 9 523 2 3815 0Table 2. Frequency <strong>of</strong> Transitions Between Statesmost qualify for benefits. Other transitions are as expected, except perhaps for UI tra<strong>in</strong><strong>in</strong>g.Indeed, the majority <strong>of</strong> participants return to UI upon completion <strong>of</strong> their program <strong>and</strong> veryfew f<strong>in</strong>d regular employment. A number <strong>of</strong> cells conta<strong>in</strong> few or no observations. <strong>The</strong> emptycells are consistent with program or policy parameters that prevent a number <strong>of</strong> transitionsto occur or are a consequence <strong>of</strong> our def<strong>in</strong>itions <strong>of</strong> the various states. 10 Only transitionscompris<strong>in</strong>g more than 75 observations will be considered <strong>in</strong> the econometric model. Thisleaves a total <strong>of</strong> 24 transitions to be modeled explicitly.<strong>The</strong> transitions on the labour market have three essential dimensions: the state <strong>of</strong> orig<strong>in</strong>, thestate <strong>of</strong> dest<strong>in</strong>ation <strong>and</strong> the duration <strong>in</strong> any a given state. Table 2 provides useful <strong>in</strong>formationon the first two dimensions. One way to represent all three dimensions simultaneously isto look at the distribution <strong>of</strong> the sample across all seven states on a weekly basis. Thisdistribution synthesizes both the transitions across states <strong>and</strong> the mean duration <strong>in</strong> each.Figure 1 plots the proportion <strong>of</strong> <strong>in</strong>dividuals <strong>in</strong> each <strong>of</strong> the seven states on a weekly basis.<strong>The</strong> top portion <strong>of</strong> the figure traces out the proportion <strong>of</strong> <strong>in</strong>dividuals <strong>in</strong> non-tra<strong>in</strong><strong>in</strong>gstates (welfare, unemployment, employment, OLF), <strong>and</strong> the bottom portion traces out theproportions <strong>in</strong> tra<strong>in</strong><strong>in</strong>g states (UI tra<strong>in</strong><strong>in</strong>g, welfare tra<strong>in</strong><strong>in</strong>g <strong>and</strong> JRP). <strong>The</strong>re are two dist<strong>in</strong>ctfeatures that arise <strong>in</strong> January 1987 <strong>in</strong> the top portion <strong>of</strong> the figure. First, the proportion <strong>of</strong><strong>in</strong>dividuals <strong>in</strong> OLF is relatively high. This partly reflects a cohort effect. In January 1987, oursample comprises only <strong>in</strong>dividuals that are 18 or 19 years <strong>of</strong> age. Not surpris<strong>in</strong>gly, a largeproportion <strong>of</strong> them are either still <strong>in</strong> school or have not yet entered the labour market. Aswe move rightward along the time axis, these <strong>in</strong>dividuals become older <strong>and</strong> new 18-19 yearold entrants jo<strong>in</strong> the sample. By the time we reach December 1993, the oldest <strong>in</strong>dividualsare between 25–26 years <strong>of</strong> age. It does not necessarily follow that the sample’s average age<strong>in</strong>creases systematically along the time axis. Proportionately more <strong>in</strong>dividuals have enteredthe sample <strong>in</strong> the recession years 1989–1992 than previously. Second, the proportion <strong>of</strong>unemployed <strong>in</strong>dividuals is zero. As mentioned earlier, the <strong>in</strong>formation on unemploymentspells is only available as <strong>of</strong> January 1987. Consequently, only new spells are identifiable <strong>in</strong>the data. Spells that were ongo<strong>in</strong>g <strong>in</strong> January 1987 are classified as OLF <strong>in</strong> the figure.<strong>The</strong> bottom portion <strong>of</strong> the figure also <strong>in</strong>dicates that the proportion <strong>of</strong> <strong>in</strong>dividuals <strong>in</strong> JRP is zeroup until approximately January-February 1990. This program was implemented <strong>in</strong> August10 For example, the welfare files provide <strong>in</strong>formation on a monthly basis. Any <strong>in</strong>terruption last<strong>in</strong>gbetween 1-3 weeks will not be recorded <strong>in</strong> the data. <strong>The</strong> record will show an un<strong>in</strong>terrupted sequence <strong>of</strong>monthly benefits receipt. Thus Welfare-Welfare transitions are not identifiable <strong>in</strong> the data. On the otherh<strong>and</strong>, UI spells are recorded on a weekly basis. Unemployed workers that work a number <strong>of</strong> weeksor hours while claim<strong>in</strong>g benefits may qualify for additional benefits once they exhaust their orig<strong>in</strong>alentitlement. <strong>The</strong> SV files will <strong>in</strong>dicate a new UI spell start<strong>in</strong>g the week follow<strong>in</strong>g exhaustion. ThusUI-UI transitions are identifiable <strong>in</strong> the data.


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 753Fig. 1. Distribution Across StatesFig. 2. Distribution Across Tra<strong>in</strong><strong>in</strong>g Programs1989 <strong>and</strong> had too few participants <strong>in</strong> the beg<strong>in</strong>n<strong>in</strong>g months to show up <strong>in</strong> the figure. Similarly,participation <strong>in</strong> UI tra<strong>in</strong><strong>in</strong>g programs is essentially zero up until February-March 1987. UItra<strong>in</strong><strong>in</strong>g usually occurs after a number <strong>of</strong> weeks has been spent unemployed. Not surpris<strong>in</strong>gly,then, a certa<strong>in</strong> laps <strong>of</strong> time is needed before the proportion <strong>of</strong> UI tra<strong>in</strong>ees is large enough toshow up <strong>in</strong> the figure. Tra<strong>in</strong><strong>in</strong>g spells that were ongo<strong>in</strong>g <strong>in</strong> January 1987 are also classified asOLF.A close look at Figure 1 reveals <strong>in</strong>terest<strong>in</strong>g patterns. First, the proportion <strong>of</strong> welfareparticipants rema<strong>in</strong>s relatively constant between 1987 <strong>and</strong> 1989. <strong>The</strong> economic downturn <strong>of</strong>1989 results <strong>in</strong> an steady <strong>in</strong>crease <strong>in</strong> the proportion <strong>of</strong> welfare claimants until the end <strong>of</strong> 1993.In fact, the proportion <strong>in</strong>creased from 17.9% <strong>in</strong> January 1988 to 42.3% <strong>in</strong> December 1993. Suchan <strong>in</strong>crease results from both a more important <strong>in</strong>flow <strong>in</strong>to welfare <strong>and</strong> longer spell duration[see Duclos et al. (1999) for details].<strong>The</strong> proportion <strong>of</strong> employed <strong>in</strong>dividuals follows a very dist<strong>in</strong>ct seasonal pattern with peaksoccurr<strong>in</strong>g around June-July <strong>and</strong> troughs around January <strong>of</strong> each year. Despite these seasonalfluctuations, the proportion <strong>of</strong> employed <strong>in</strong>dividuals <strong>in</strong>creased from 31.2% <strong>in</strong> January 1988 to33.5% <strong>in</strong> January 1990, <strong>and</strong> then gradually decl<strong>in</strong>ed to 18.6% <strong>in</strong> January 1993. <strong>The</strong> proportion<strong>of</strong> unemployed <strong>in</strong>dividuals is highly negatively correlated with the proportion <strong>of</strong> employed<strong>in</strong>dividuals. <strong>The</strong> seasonal fluctuations almost perfectly mirror those <strong>of</strong> employment. F<strong>in</strong>ally,the proportion <strong>of</strong> <strong>in</strong>dividuals <strong>in</strong> the OLF state also depicts strong seasonal patterns. In January<strong>of</strong> each year, the proportion <strong>of</strong> those <strong>in</strong> OLF <strong>in</strong>creases by about 5 percentage po<strong>in</strong>ts. It is likely


54 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications8 Will-be-set-by-IN-TECHthat many seasonal workers lose their job at the beg<strong>in</strong>n<strong>in</strong>g <strong>of</strong> each year <strong>and</strong> do not qualify forunemployment benefits.<strong>The</strong> bottom portion <strong>of</strong> the figure shows that the proportion <strong>of</strong> <strong>in</strong>dividuals engaged <strong>in</strong>government-sponsored tra<strong>in</strong><strong>in</strong>g programs fluctuates considerably over time. A number <strong>of</strong>new welfare tra<strong>in</strong><strong>in</strong>g programs have been implemented <strong>in</strong> 1989. Most <strong>of</strong> these programsaim at enhanc<strong>in</strong>g job search skills <strong>and</strong> usually last a few weeks. <strong>The</strong> large <strong>in</strong>crease <strong>in</strong>the proportion <strong>of</strong> welfare tra<strong>in</strong>ees co<strong>in</strong>cide with the implementation <strong>of</strong> these programs. Adramatic fall occurs towards the end <strong>of</strong> 1989 presumably l<strong>in</strong>ked to budgetary constra<strong>in</strong>tsassociated with the economic downturn <strong>of</strong> 1990. <strong>The</strong> proportion <strong>of</strong> participants steadily<strong>in</strong>creases thereafter <strong>and</strong> reaches its peak at the end <strong>of</strong> 1993. <strong>The</strong> proportion <strong>of</strong> UI tra<strong>in</strong>eesis relatively constant throughout the whole period, with the exception <strong>of</strong> 1992. Both the UItra<strong>in</strong><strong>in</strong>g programs <strong>and</strong> JRP have relatively few participants at any po<strong>in</strong>t <strong>in</strong> time.<strong>The</strong> proportions <strong>of</strong> participants <strong>in</strong> the comb<strong>in</strong>ed programs hardly reach beyond 5% over thesample period. <strong>The</strong> fact that few <strong>in</strong>dividuals are engaged <strong>in</strong> formal tra<strong>in</strong><strong>in</strong>g at any po<strong>in</strong>t <strong>in</strong>time is no <strong>in</strong>dication that tra<strong>in</strong><strong>in</strong>g programs are <strong>in</strong>efficient or unattractive. Access to programsis <strong>of</strong>ten limited because <strong>of</strong> <strong>in</strong>sufficient resources. This lack <strong>of</strong> resources raises a fundamentalquestion: who gets selected <strong>in</strong>to tra<strong>in</strong><strong>in</strong>g? To the econometrician, participation <strong>in</strong> a tra<strong>in</strong><strong>in</strong>gprogram is the result <strong>of</strong> two separate unidentifiable processes. First, the participant hasundertaken the necessary steps to take part <strong>in</strong> the program. Second, the program managerhas deemed the participant eligible. <strong>The</strong>se two processes are likely to be such that participantshave unobservable (to the econometrician) characteristics that are systematically differentfrom those <strong>of</strong> the non-participants. Fortunately, given the <strong>in</strong>formation at our disposal itis possible to devise estimators that, under very general assumptions, will yield unbiasedestimates <strong>of</strong> the programs’ impacts. <strong>The</strong>se estimators are presented <strong>in</strong> the next section.3. Model<strong>in</strong>g labour market transitions<strong>The</strong> labour market history <strong>of</strong> a given <strong>in</strong>dividual is represented by a sequence <strong>of</strong> n spells <strong>of</strong>various lengths <strong>in</strong> any <strong>of</strong> K (=7) states 11 . Let x t be the state <strong>in</strong> which an <strong>in</strong>dividual is observedto be at time t. <strong>The</strong> sequence starts at calendar time τ 0 = 0 when the <strong>in</strong>dividual is 16 years <strong>of</strong>age <strong>and</strong> ends at time τ e (τ e = December 1993). Figure 3 depicts a hypothetical sequence madeup <strong>of</strong> 3 spells <strong>of</strong> various length <strong>in</strong> 3 different states. As depicted, the <strong>in</strong>dividual is <strong>in</strong>itiallyobserved <strong>in</strong> the OLF state. He enters <strong>in</strong>to employment at time τ 1 <strong>and</strong> eventually moves <strong>in</strong>tounemployment at time τ 2 . At time τ e he is still <strong>in</strong> the midst <strong>of</strong> an unemployment spell.Let τ l denote the calendar time at which a spell <strong>in</strong> any given state ends. Each spell l (1 ≤l ≤ n) is thus delimited by the start time τ l−1 <strong>and</strong> the end time τ l (τ l > τ l−1 ). Let u l be theduration <strong>of</strong> spell l (u l = τ l − τ l−1 ). F<strong>in</strong>ally, let r denote a complete sequence from time 0 totime τ e :r =((u 1 , x τ1 ),...,(u n−1 , x τn−1 ), (u n ,0)),where u n = τ e − τ n−1 is the duration <strong>of</strong> the last spell. <strong>The</strong> last spell <strong>of</strong> each <strong>in</strong>dividual isright-censored s<strong>in</strong>ce τ n <strong>and</strong> x τn are not observed. On the other h<strong>and</strong>, the last spell musthave lasted at least τ n − τ n−1 units <strong>of</strong> time <strong>in</strong> state x τn−1 . Because x τn is not observed weconventionally fix x τn = 0.11 See Fougère & Kamionka (2008) for a more general presentation <strong>of</strong> the econometrics <strong>of</strong> transitionmodels.


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 9x t✻55OLFEmp.UI Tr.UI✲JRPWel. Tr.Welfare0τ 1τ 2Fig. 3. Labour market history <strong>of</strong> a hypothetical <strong>in</strong>dividual.τ e✲t<strong>The</strong> sequence may be more compactly rewritten as:wherey l =r =(y 1 ,...,y n ),{(ul , x τl ), if 1 ≤ l ≤ n − 1,(u n ,0), if l = n.<strong>The</strong> <strong>in</strong>itial state, x 0 , is the same for each <strong>in</strong>dividual <strong>in</strong> our sample <strong>and</strong> is exogenouslydeterm<strong>in</strong>ed by school attendance laws. Consequently, there is no need to explicitly modelthe <strong>in</strong>itial state <strong>in</strong> which <strong>in</strong>dividuals are observed.3.1 Likelihood functionEach <strong>in</strong>dividual contributes a sequence r = (y 1 ,...,y n ) to the likelihood function. <strong>The</strong>contribution can be written conditionally on a vector <strong>of</strong> exogenous variables, z, <strong>and</strong> anunobserved heterogeneity factor, ν.Let l v (θ) denote the conditional contribution <strong>of</strong> the sequence r. We have,nl v (θ) = ∏ f (y l | y 1 ,...,y l−1 ; z; ν; θ),l=1where f (y l | y 1 ,...,y l−1 ; z; ν; θ) is the conditional density <strong>of</strong> y l given y 1 , ..., y l−1 , z <strong>and</strong> ν,<strong>and</strong> θ ∈ Θ ⊂ IR p is a vector <strong>of</strong> parameters. Naturally, the dest<strong>in</strong>ation state <strong>of</strong> the last spell isunknown s<strong>in</strong>ce the duration is censored. Its contribution to the conditional likelihood functionis limited to the survivor function <strong>of</strong> the observed duration.<strong>The</strong> r<strong>and</strong>om variable ν is assumed to be <strong>in</strong>dependently <strong>and</strong> identically distributedacross <strong>in</strong>dividuals, <strong>and</strong> <strong>in</strong>dependent from the exogenous variables z. If the unobserved


56 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications10 Will-be-set-by-IN-TECHheterogeneity can take only a f<strong>in</strong>ite number <strong>of</strong> values, ν 1 ,...,ν J , the contribution <strong>of</strong> a sequencer to the likelihood function isl(θ) =J n∑ ∏ f (y l | y 1 ,...,y l−1 ; z; ν j ; θ) π j , (1)j=1 l=1where π j is the probability that the unobserved heterogeneity term takes the value ν j (0 ≤π j ≤ 1, ∑ J j=1 π j = 1).If ν is a cont<strong>in</strong>uous r<strong>and</strong>om variable, then∫l(θ) =n∏ f (y l | y 1 ,...,y l−1 ; z; ν; θ) g(ν; γ) d ν, (2)Vl=1where g(ν; γ) is a density probability function <strong>and</strong> V is the support <strong>of</strong> ν.Furthermore, if we assume that Y l is <strong>in</strong>dependent <strong>of</strong> Y 1 ,...,Y l−2 , given Y l−1 = y l−1 , Z = z<strong>and</strong> the value <strong>of</strong> the unobserved term ν, thenf (y l | y 1 ,...,y l−1 ; z; ν; θ) = f (y l | y l−1 ; z; ν; θ).Given the history <strong>of</strong> the process, the jo<strong>in</strong>t distribution <strong>of</strong> the duration <strong>of</strong> spell l <strong>and</strong> thedest<strong>in</strong>ation state only depends on the current state on the labour market. This assumptionwill be relaxed by <strong>in</strong>troduc<strong>in</strong>g other characteristics <strong>of</strong> the history <strong>of</strong> the process.3.2 Model<strong>in</strong>g <strong>in</strong>dividual spellsIn this section we focus on the conditional distribution <strong>of</strong> y l= (u l , x τl ), where u l is theduration <strong>of</strong> the l th spell <strong>in</strong> state x τl−1 . Def<strong>in</strong>e u ∗ l,k as the wait<strong>in</strong>g time before leav<strong>in</strong>g state x τ l−1for state x τl . At the end <strong>of</strong> the l th spell, the <strong>in</strong>dividual will enter <strong>in</strong>to the state correspond<strong>in</strong>gto the smallest latent duration u ∗ l,k ′ . We will assume that these K latent durations are<strong>in</strong>dependently distributed. Thus the duration <strong>of</strong> spell l is given by 12u l = <strong>in</strong>fk ′ u ∗ l,k ′.Let f j (u | y 1 ,...,y l−1 ; z; ν; θ) denote the probability density function (p.d.f.) <strong>of</strong> the latentduration u ∗ l,j , given the history <strong>of</strong> the process up to time τ l−1, ν <strong>and</strong> covariates z. Let S j (u |y 1 ,...,y l−1 ; z; ν; θ) be the correspond<strong>in</strong>g survivor function:S j (u | y 1 ,...,y l−1 ; z; ν; θ) =∫ +∞f j (s | y 1 ,...,y l−1 ; z; ν; θ) ds.u12 If the transition from state i to state j cannot be observed, we assume that the correspond<strong>in</strong>g latentdistribution is defective <strong>and</strong> set a probability mass equal to one on +∞.


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 1157<strong>The</strong> conditional jo<strong>in</strong>t density <strong>of</strong> the duration <strong>of</strong> spell l <strong>and</strong> the dest<strong>in</strong>ation state k is given bythe follow<strong>in</strong>g expressionf (u, k|y 1 ,...,y l−1 ; z; ν; θ) = f k (u | y 1 ,...,y l−1 ; z; ν; θ)KS j (u | y 1 ,...,y l−1 ; z; ν; θ),∏j=1j̸=k= h k (u|y 1 ,...,y l−1 ; z; ν; θ) S(u|y 1 ,...,y l−1 ; z; ν; θ),where h k (u | y 1 ,...,y l−1 ; z; ν; θ) is the hazard function associated with the latent duration u ∗ l,k<strong>and</strong> S(u | y 1 ,...,y l−1 ; z; ν; θ) is the survivor function <strong>of</strong> the duration <strong>of</strong> the l th spell. Becausethe latent durations are assumed to be conditionally <strong>in</strong>dependent we haveS(u | y 1 ,...,y l−1 ; z; ν; θ) =K∏ S j (u | y 1 ,...,y l−1 ; z; ν; θ),j=1where u ≥ 0. <strong>The</strong> expression represents the conditional probability that the duration <strong>of</strong> spell lis at least equal to u or, equivalently, that all latent durations are at least equal to u. <strong>The</strong>refore,the conditional contribution <strong>of</strong> a given sequence to the likelihood function is:n Kl v (θ) = ∏ ∏ h k (u | y 1 ,...,y l−1 ; z; ν; θ) δ l,kS k (u | y 1 ,...,y l−1 ; z; ν; θ),l=1 k=1where δ l,k is equal to 1 if the <strong>in</strong>dividual enters <strong>in</strong>to state k at the end <strong>of</strong> spell l <strong>and</strong> to 0otherwise :l = 1,...,n.δ l,k ={ 1, if xτl = k,0, otherwise,3.3 Unobserved heterogeneitySo far the discussion surround<strong>in</strong>g the unobserved heterogeneity components has voluntarilybeen kept general. <strong>The</strong> use <strong>of</strong> maximum likelihood procedures requires that we specifydistribution functions for these components. Most applications rely on the work <strong>of</strong> Heckman& S<strong>in</strong>ger (1984) <strong>and</strong> approximate arbitrary cont<strong>in</strong>uous distributions us<strong>in</strong>g a f<strong>in</strong>ite number <strong>of</strong>mass po<strong>in</strong>ts (see Gritz (1993), Ham & Rea (1987), Doiron & Gorgens (2008)). More recentpapers use richer specifications that allow the heterogeneity terms to be correlated acrossstates (see Bonnal et al. (1997), Ham & LaLonde (1996)). <strong>The</strong>se specifications are sometimesreferred to as s<strong>in</strong>gle or two-factor load<strong>in</strong>g distributions <strong>and</strong> are also based on a f<strong>in</strong>ite set <strong>of</strong>mass po<strong>in</strong>ts. In our work, we wish to <strong>in</strong>vestigate the robustness <strong>of</strong> the parameter estimatesto various distributional assumptions. We will use two <strong>and</strong> three-factor load<strong>in</strong>g distributionsas <strong>in</strong> the aforementioned papers. Additionally, we will <strong>in</strong>vestigate the consequences on theslope parameters <strong>of</strong> us<strong>in</strong>g various cont<strong>in</strong>uous distributions <strong>in</strong>stead <strong>of</strong> the usual f<strong>in</strong>ite sets <strong>of</strong>mass po<strong>in</strong>ts.


58 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications12 Will-be-set-by-IN-TECHTo fix ideas, let w =(w 1 ,...,w K ) be a vector <strong>of</strong> unobserved heterogeneity variables, with w k adest<strong>in</strong>ation-specific component (k = 1,...,K). Ideally, the jo<strong>in</strong>t distribution <strong>of</strong> the unobservedheterogeneity terms should not be <strong>in</strong>dependent.Consider first a two-factor load<strong>in</strong>g model (see Van den Berg (1997)) such thatw k = exp(a k v 1 + b k v 2 ), (3)where v 1 ∈{−2, c 2 }, v 2 ∈{c 1 , c 2 }, b k ∈ IR, a k = 1I[k ≥ 2] <strong>and</strong> b 1 = 1. <strong>The</strong> r<strong>and</strong>om variablesv 1 <strong>and</strong> v 2 are assumed to be <strong>in</strong>dependent. <strong>The</strong> constra<strong>in</strong>ts imposed on the support <strong>of</strong> v 1 <strong>and</strong>v 2 are sufficient for identification <strong>and</strong> to allow the correlation between log(w k ) <strong>and</strong> log(w k ′ )to span the <strong>in</strong>terval [−1; 1].Moreover, assume thatProb[(V 1 , V 2 )=(v 0 1 , v0 2 )] = ⎧⎪ ⎨⎪ ⎩p 2 , if v 0 1 = −2 <strong>and</strong> v0 2 = c 1,p ∗ (1 − p), if v 0 1 = −2 <strong>and</strong> v0 2 = c 2,(1 − p) ∗ p, if v 0 1 = c 2 <strong>and</strong> v 0 2 = c 1,(1 − p) 2 , if v 0 1 = c 2 <strong>and</strong> v 0 2 = c 2,where c 1 , c 2 ∈ IR <strong>and</strong> the probability p is def<strong>in</strong>ed as(4)p =exp(d)1 + exp(d) ,where d ∈ IR is a parameter.<strong>The</strong> correlation between log(w k ) <strong>and</strong> log(w k ′ ), denoted ρ k,k ′,isρ k,k ′ =a k a k ′ σ 2 v 1+ b k b k ′ σ 2 v 2√a 2 k σ2 v 1+ b 2 k σ2 v 2√a 2 k ′ σ 2 v 1+ b 2 k ′ σ 2 v 2, (5)where k, k ′ = 1, . . . , K <strong>and</strong> σv 2 jis the variance <strong>of</strong> v j , j=1,2. A positive correlation coefficientbetween w j <strong>and</strong> w k implies that those who are likely to have high transition rates between anygiven state <strong>and</strong> state j will also have high transition rates <strong>in</strong>to state k.A two-factor load<strong>in</strong>g model with two <strong>in</strong>dependent heterogeneity terms with commoncont<strong>in</strong>uous distribution can also be derived from this specification. As before, let w k denotethe heterogeneity term for dest<strong>in</strong>ation k:w k = exp(a k v 1 + b k v 2 ),where a k <strong>and</strong> b k are parameters (a k = 1I[k ≥ 2] <strong>and</strong> b 1 = 1).Here v 1 <strong>and</strong> v 2 are assumed to be <strong>in</strong>dependently <strong>and</strong> identically distributed. Let q(v; γ) bethe p.d.f. <strong>of</strong> v 1 <strong>and</strong> v 2 . <strong>The</strong> correlations between log(w k ) <strong>and</strong> log(w k ′ ) are given by the sameexpression as <strong>in</strong> (5). In pr<strong>in</strong>ciple, q(v; γ) represents any well-behaved distribution function.<strong>The</strong> above specification can be further generalized to a three-factor load<strong>in</strong>g model withcommon cont<strong>in</strong>uous distribution. In this case the unobserved components depend on thedest<strong>in</strong>ation state as well as the current state. Let w j,k be specific to the transition betweenorig<strong>in</strong> j <strong>and</strong> dest<strong>in</strong>ation k.w j,k = w ′ j w k = exp(a ′ j v 3 + b ′ j v 2) × exp(a k v 1 + b k v 2 ), (6)where a ′ j , b′ j , a k <strong>and</strong> b k are parameters (a ′ j = a k = 1I[k ≥ 2], b 1 = 1).


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 1359In this three-factor load<strong>in</strong>g model, the correlation between dest<strong>in</strong>ation states k <strong>and</strong> k ′ isaρ k,k ′ = k a k ′ + b k b k ′√. (7)a 2 k + b2 k√a 2 k+ ′ bk 2 ′This correlation has the same <strong>in</strong>terpretation as <strong>in</strong> the two-factor load<strong>in</strong>g model.On the other h<strong>and</strong>, the correlation between the two orig<strong>in</strong> states j <strong>and</strong> j ′ is given byρ j,j ′ =a ′ j a ′ j ′ + b′ j b ′ j√√a ′. (8)′ 2j + b ′ 2j a ′ 2j ′ + b ′ 2j ′A positive correlation <strong>in</strong>dicates that those who have short spells <strong>in</strong> state j are likely to haveshort spell duration <strong>in</strong> state j ′ as well.F<strong>in</strong>ally, the correlation between orig<strong>in</strong> state j <strong>and</strong> dest<strong>in</strong>ation state k is given byb ′ j b kρ k,j =√ , √a ′ 2j + b ′ 2j a 2 k + b2 k(9)where j, j ′ , k, k ′ = 1, . . . , K. This correlation is somewhat trickier to <strong>in</strong>terpret. A positivecoefficient <strong>in</strong>dicates that those who are likely to have short spell duration <strong>in</strong> state j are alsomore likely to enter state k. Conversely, those who are more likely to have short spell duration<strong>in</strong> state j are less likely to enter state k.3.4 Specification <strong>of</strong> conditional hazard functionsAssume an <strong>in</strong>dividual is observed <strong>in</strong> state j dur<strong>in</strong>g spell l (i.e. x τl−1 = j). Let ψ(j, k) denotethe heterogeneity term for dest<strong>in</strong>ation k, given the <strong>in</strong>dividual is <strong>in</strong> state j. <strong>The</strong>re are twopossibilities:{ wk , <strong>in</strong> the two-factor load<strong>in</strong>g model,ψ(j, k) =w j,k , <strong>in</strong> the three-factor load<strong>in</strong>g model.<strong>The</strong> conditional hazard function for transition (j, k) is given byh j,k (u | y 1 ,...,y l−1 ; z; ν; θ) =h 0 j,k (u; θ) ϕ(y 1,...,y l−1 ; z; θ) ψ(j, k), (10)where ϕ is a positive function <strong>of</strong> the exogenous variables <strong>and</strong> the sequence r, h 0 j,k (u; θ) is thebasel<strong>in</strong>e hazard function for transition (j, k), <strong>and</strong> ψ(j, k) > 0.We have considered three alternative conditional specifications for the basel<strong>in</strong>e hazardfunctions. For each transition, we have chosen among the follow<strong>in</strong>g compet<strong>in</strong>g specificationson the basis <strong>of</strong> non-parametric kernel estimations (see Fort<strong>in</strong> et al. (1999a)):1. Log-logistic Distribution<strong>The</strong> basel<strong>in</strong>e hazard function isα j,k , β j,k ∈ IR + .h 0 j,k (u; θ) = β j,k α j,k u α j,k−1(1 + β j,k u α j,k) ,


60 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications14 Will-be-set-by-IN-TECHIf α j,k > 1 then the hazard function is <strong>in</strong>creas<strong>in</strong>g then decreas<strong>in</strong>g with respect <strong>of</strong> u. Ifα j,k ≤ 1 then the hazard function is decreas<strong>in</strong>g.2. Piecewise-Constant Hazard Model<strong>The</strong> expression <strong>of</strong> the basel<strong>in</strong>e hazard function ish 0 j,k (u; θ) =α j,k1I[u < u 0 1 ]+β j,k1I[u 0 1 ≤ u < u0 2 ]+γ j,k1I[u 0 2 ≤ u],where α j,k , β j,k , γ j,k ∈ IR + . u 0 1 <strong>and</strong> u0 2 are fixed.<strong>The</strong> basel<strong>in</strong>e hazard function can be <strong>in</strong>creas<strong>in</strong>g then decreas<strong>in</strong>g,<strong>in</strong>creas<strong>in</strong>g, strictly <strong>in</strong>creas<strong>in</strong>g or strictly decreas<strong>in</strong>g.3. Weibull Distribution<strong>The</strong> basel<strong>in</strong>e hazard function isdecreas<strong>in</strong>g thenh 0 j,k (u; θ) =α j,k β j,k u α j,k−1 ,α j,k , β j,k ∈ IR + .If α j,k > 1 then the hazard function is <strong>in</strong>creas<strong>in</strong>g with respect <strong>of</strong> u. If α j,k < 1 then thehazard function is decreas<strong>in</strong>g with respect <strong>of</strong> u <strong>and</strong> if α j,k = 1 this conditional hazardfunction is constant.3.5 <strong>Estimation</strong>We consider three alternative specifications for the unobserved heterogeneity distribution.1. Two-Factor Load<strong>in</strong>g <strong>and</strong> Discrete Distribution<strong>The</strong> log likelihood isNlog(L(θ)) = ∑ log(l i (θ)), (11)i=1where l i (θ) is obta<strong>in</strong>ed by substitut<strong>in</strong>g the sequence r i =(y 1,i ,...,y ni ,i) <strong>and</strong> the observedvector <strong>of</strong> covariates z i <strong>in</strong> (1). N is the size <strong>of</strong> the sample.In equation (1) π j is set equal to 13⎧⎨ p 2 , if j = 1,π j = p ∗ (1 − p), if j = 2, 3,⎩(1 − p) 2 , if j = 4,where p ∈ [0; 1] is a parameter. <strong>The</strong> log-likelihood is then maximized with respect <strong>of</strong> θ(θ ∈ Θ).2. Two-Factor Load<strong>in</strong>g <strong>and</strong> Cont<strong>in</strong>uous Distribution<strong>The</strong> model <strong>in</strong>cludes two unobserved heterogeneity terms v 1 <strong>and</strong> v 2 (v j > 0, j = 1, 2). Weassume these terms to be <strong>in</strong>dependently <strong>and</strong> identically distributed. Let q(v; γ) be thep.d.f. <strong>of</strong> v j , j = 1, 2.<strong>The</strong> contribution <strong>of</strong> a given realization to the likelihood function is given by equation (2),where ν =(v 1 , v 2 ) ′ , V = IR + × IR + <strong>and</strong> g(ν; γ) =q(v 1 ; γ) q(v 2 ; γ). <strong>The</strong> log-likelihood is13 See section 4.


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 1561given by equation (11), where l i (θ) is the contribution to the likelihood <strong>of</strong> the sequence r i . 14S<strong>in</strong>ce the <strong>in</strong>tegral <strong>in</strong> l(θ) cannot generally be analytically computed it must be numericallysimulated.Let ˆl(θ) denote the estimator <strong>of</strong> the <strong>in</strong>dividual contribution to the likelihood function. Weassume thatˆl(θ) = 1 H nH∑ ∏ f (y l | y 1 ,...,y l−1 ; z; v 1,h , v 2,h ; θ),h=1 l=1where v 1,h <strong>and</strong> v 2,h are drawn <strong>in</strong>dependently accord<strong>in</strong>g to the p.d.f. q(v; γ). <strong>The</strong> draw<strong>in</strong>gsv j,h (j = 1, 2, h = 1, . . . , H) are assumed to be specific to the <strong>in</strong>dividual. <strong>The</strong> parameterestimates are obta<strong>in</strong>ed by maximiz<strong>in</strong>g the simulated log-likelihood:Nlog(L(θ)) = ∑ log(ˆl i (θ)),i=1where ˆl i (θ) is the simulated contribution <strong>of</strong> the sequence r i to the likelihood function.<strong>The</strong> maximization <strong>of</strong> this simulated likelihood yields consistent <strong>and</strong> efficient parameters√estimates if NH→ 0 when H → +∞ <strong>and</strong> N → +∞ (see Gourriéroux & Monfort(1991)). Under these conditions, this estimator has the same asymptotic distribution as thest<strong>and</strong>ard ML estimator. Follow<strong>in</strong>g Laroque & Salanié (1993), Kamionka (1998) <strong>and</strong> Edon &Kamionka (2007) we have used 20 draws from the r<strong>and</strong>om distributions when estimat<strong>in</strong>gthe models. Us<strong>in</strong>g as few as 10 draws yielded essentially the same parameter estimates.3. Three-Factor Load<strong>in</strong>g <strong>and</strong> Cont<strong>in</strong>uous DistributionIn the three-factor load<strong>in</strong>g model the conditional contribution must be <strong>in</strong>tegrated withrespect to the distribution <strong>of</strong> three <strong>in</strong>dependent unobserved heterogeneity terms. Let ˆl(θ)denote the estimator <strong>of</strong> the <strong>in</strong>dividual contribution to the likelihood function. Assumefurther thatˆl(θ) = 1 H nH∑ ∏ f (y l | y 1 ,...,y l−1 ; z; v 1,h , v 2,h , v 3,h ; θ),h=1 l=1where v 1,h , v 2,h <strong>and</strong> v 3,h are drawn <strong>in</strong>dependently accord<strong>in</strong>g to the p.d.f. q(ν; γ). Onceaga<strong>in</strong>, the parameter estimates obta<strong>in</strong>ed from maximiz<strong>in</strong>g this function are asymptoticallyefficient.4. <strong>Estimation</strong> resultsThis section presents the results <strong>of</strong> fitt<strong>in</strong>g the models outl<strong>in</strong>ed <strong>in</strong> the previous section to thedata at our disposal. <strong>The</strong> estimation <strong>of</strong> such complex models is computationally dem<strong>and</strong><strong>in</strong>g.Also, a number <strong>of</strong> issues must be addressed before dwell<strong>in</strong>g <strong>in</strong>to the results.4.1 Functional forms assumptionsAs mentioned <strong>in</strong> the previous section, it is necessary to specify a basel<strong>in</strong>e distribution functionfor each transition considered <strong>in</strong> the model. When select<strong>in</strong>g a particular functional form, a14 In what follows, θ <strong>in</strong>cludes γ, the parameters <strong>of</strong> q(·).


62 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications16 Will-be-set-by-IN-TECHnumber <strong>of</strong> desirable properties should be sought. First, the functional form should allow anumber <strong>of</strong> different shapes <strong>of</strong> the hazard function so that various comb<strong>in</strong>ations <strong>of</strong> positive<strong>and</strong> negative duration dependence are possible. Second, it should roughly follow the pattern<strong>of</strong> transitions times found <strong>in</strong> the data. F<strong>in</strong>ally, the functional forms should <strong>in</strong>volve as fewparameters as possible.Dest. Welfare Welfare JRP U.I. U.I. Emp. OLFOrig<strong>in</strong> Tra<strong>in</strong><strong>in</strong>g Tra<strong>in</strong><strong>in</strong>gWelfare Exp (1) Exp (1) Exp (1) Exp (3) Exp (1)Wel Tr Log-logis. Log-logis. Log-logis.JRP Exp (1)U.I. Exp (2) Exp (2) Exp (1) Exp (3) Exp (2)U.I. Tr Exp (1)Emp Log-logis. Weibull Log-logis. Log-logis. Log-logis.OLF Exp (2) Exp (2) Exp (2) Exp (2)Table 3. Basel<strong>in</strong>e Hazard Functional Forms†† “Exp” refers to exponential piecewise constant hazard model. <strong>The</strong> number <strong>of</strong> parameters are <strong>in</strong>dicatedbetween parentheses.<strong>The</strong> data at our disposal was analyzed <strong>in</strong> Fort<strong>in</strong> et al. (1999a) <strong>and</strong> Fort<strong>in</strong> et al. (2004) us<strong>in</strong>gnon-parametric kernel hazard estimators. <strong>The</strong> basel<strong>in</strong>e hazard functions were chosen onthe basis <strong>of</strong> their analysis. Table 3 reports the functional form used <strong>in</strong> each <strong>of</strong> the 24transitions considered <strong>in</strong> the model. Both the log-logistic <strong>and</strong> the piecewise constant functionsallow non-monotonic hazards. For many transitions, the empirical hazard functions <strong>in</strong>itially<strong>in</strong>crease for a short period <strong>of</strong> time <strong>and</strong> then display an extended period <strong>of</strong> negative durationdependence. <strong>The</strong> log-logistic function is best suited <strong>in</strong> these cases. When the empiricalhazard function looks relatively flat, it is preferable to use an exponential model with as<strong>in</strong>gle parameter. Other non-monotone shapes are best approximated with the piecewiseconstant hazard function. Monotone <strong>in</strong>creas<strong>in</strong>g or decreas<strong>in</strong>g empirical hazard rates can besatisfactorily approximated with a weibull distribution function.4.2 Exogenous covariatesMost studies on labour market transitions <strong>in</strong>clude a number <strong>of</strong> exogenous <strong>in</strong>dividual-specific<strong>and</strong> macroeconomic variables. It is thus customary to <strong>in</strong>clude variables such as age, sex,education <strong>and</strong> m<strong>in</strong>ority status to capture behavioural differences across these groups. In thischapter we have tried to limit the number <strong>of</strong> exogenous control variables as much as possible.Given the unusually large number <strong>of</strong> transitions considered <strong>in</strong> the analysis, <strong>in</strong>clud<strong>in</strong>g even aslittle as 10 exogenous variables would have over-parameterized the likelihood function <strong>and</strong>rendered its estimation practically <strong>in</strong>feasible.An alternative empirical strategy is to circumscribe the sample to relatively homogeneous<strong>in</strong>dividuals <strong>in</strong> terms <strong>of</strong> observable characteristics. We have elected to concentrate our attentionon young <strong>and</strong> poorly educated men for two reasons: (1) <strong>The</strong>y have fared relatively poorlyon the labour market over the past two decades (see Beaudry & Green (2000)); (2) As aconsequence <strong>of</strong> their deteriorat<strong>in</strong>g labour market outcomes, many have claimed welfarebenefits <strong>and</strong> have been especially targeted for tra<strong>in</strong><strong>in</strong>g programs. Hav<strong>in</strong>g a relativelyhomogeneous sample <strong>in</strong> terms <strong>of</strong> age <strong>and</strong> education does not remove the need to controlfor such variables explicitly. Our sampl<strong>in</strong>g scheme <strong>in</strong>sures that there is little variance <strong>in</strong> ageat the start <strong>of</strong> the sample period (see Table 1). As the <strong>in</strong>itial <strong>in</strong>dividuals become older, new


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 1763entrants 18–19 years <strong>of</strong> age jo<strong>in</strong> the sample, thus <strong>in</strong>creas<strong>in</strong>g considerably the variance <strong>in</strong> age.On the other h<strong>and</strong>, the sample was chosen so that educational atta<strong>in</strong>ment never exceeded 10years <strong>of</strong> school<strong>in</strong>g. Consequently, the variance <strong>in</strong> education rema<strong>in</strong>s relatively constant overthe sample period.We thus explicitly control for age <strong>in</strong> the regressions. Note that Gritz (1993) has found botheducation <strong>and</strong> age to have little impact on any <strong>of</strong> the transitions considered <strong>in</strong> his model. <strong>The</strong>follow<strong>in</strong>g exogenous variables are <strong>in</strong>cluded <strong>in</strong> the model <strong>in</strong> addition to age: m<strong>in</strong>imum wage,unemployment rate, welfare benefits, <strong>and</strong> dummy <strong>in</strong>dicators for previous tra<strong>in</strong><strong>in</strong>g undereither welfare or UI. <strong>The</strong> m<strong>in</strong>imum wage <strong>and</strong> the welfare benefits are computed monthly<strong>and</strong> deflated by the monthly Consumer Price Index (CPI). <strong>The</strong> monthly unemployment rate iscomputed for men aged 25-64 for the Prov<strong>in</strong>ce <strong>of</strong> Québec. All the variables are computed atthe beg<strong>in</strong>n<strong>in</strong>g <strong>of</strong> each spell <strong>and</strong> are assumed constant throughout the duration <strong>of</strong> <strong>in</strong>dividualspells.4.3 Parameter estimatesTable 4 presents the parameter estimates <strong>of</strong> a three-factor load<strong>in</strong>g model that <strong>in</strong>corporatesa weibull distribution for the heterogeneity variables. 15 <strong>The</strong> slope parameters <strong>of</strong> thenon-parametric <strong>and</strong> the (weibull) two-factor load<strong>in</strong>g models are nearly identical to thosepresented <strong>in</strong> Table 4 <strong>and</strong> are not reported for the sake <strong>of</strong> brevity.Table 4 is divided <strong>in</strong>to several panels. Each panel conta<strong>in</strong>s the parameter estimates for theexit rates <strong>of</strong> a given state. <strong>The</strong> parameter estimates <strong>of</strong> the basel<strong>in</strong>e hazard are presented firstfollowed by those <strong>of</strong> the control variables. <strong>The</strong> variable “Wel Tr 1 ” is a dummy <strong>in</strong>dicator thatequals 1 if the <strong>in</strong>dividual has experienced a welfare tra<strong>in</strong><strong>in</strong>g spell or has participated <strong>in</strong> JRPat any time prior to the ongo<strong>in</strong>g spell, <strong>and</strong> 0 otherwise. <strong>The</strong> variable “Wel Tr 2 ” is a dummy<strong>in</strong>dicator that equals 1 if the state just prior to the current spell was either welfare tra<strong>in</strong><strong>in</strong>g orJRP, <strong>and</strong> 0 otherwise. <strong>The</strong> variables “UI Tr 1 ” <strong>and</strong> “UI Tr 2 ” are similarly def<strong>in</strong>ed but perta<strong>in</strong> toUI tra<strong>in</strong><strong>in</strong>g programs. <strong>The</strong> <strong>in</strong>clusion <strong>of</strong> “Wel Tr1 1 ”or“UITr 1 ” alone implicitly assumes thatthe impact <strong>of</strong> tra<strong>in</strong><strong>in</strong>g programs does not wear <strong>of</strong>f with time nor that it accumulate with repeatuses. Includ<strong>in</strong>g both “Wel Tr 1 ” <strong>and</strong> “Wel Tr 2 ”or“UITr 1 ” <strong>and</strong> “UI Tr 2 ” allows to determ<strong>in</strong>ewhether recent tra<strong>in</strong><strong>in</strong>g has more impact than previous tra<strong>in</strong><strong>in</strong>g on current spell duration.Both past <strong>and</strong> recent tra<strong>in</strong><strong>in</strong>g variables are <strong>in</strong>cluded whenever feasible.4.3.1 Exits from welfare<strong>The</strong> first panel <strong>of</strong> Table 4 focuses on exits from welfare. Exits to as many as five different statesare considered <strong>in</strong> the model. Parameters related to age <strong>in</strong>dicate that as <strong>in</strong>dividuals get olderthey are more likely to enter employment or OLF upon leav<strong>in</strong>g welfare. In the latter case, thismay be an <strong>in</strong>dication that they are more <strong>in</strong>cl<strong>in</strong>ed to return to school. Increases <strong>in</strong> the m<strong>in</strong>imumwage rate <strong>in</strong>creases the transitions towards welfare tra<strong>in</strong><strong>in</strong>g, JRP <strong>and</strong> unemployment, but hasno impact on transitions <strong>in</strong>to employment. This result is compatible with the results found15 <strong>The</strong> model was also estimated us<strong>in</strong>g normal, student-t, χ 2 <strong>and</strong> gamma distributions. <strong>The</strong> results basedon these specifications are not reported here for the sake <strong>of</strong> brevity, but are available on request. <strong>The</strong>specification based on the weibull was preferred to all others for two reasons. First, the parameterestimates based on the weibull distribution are very similar to those based on discrete distributions witha f<strong>in</strong>ite number <strong>of</strong> mass po<strong>in</strong>ts. Given the latter are robust to specification errors on the distribution<strong>of</strong> the heterogeneity components (see Heckman & S<strong>in</strong>ger (1984)), the weibull distribution appears todepict similar properties. Second, as <strong>in</strong> Heckman & S<strong>in</strong>ger (1984), the value <strong>of</strong> likelihood functionbased on the weibull distribution is larger than those based on other distributions.


64 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications18 Will-be-set-by-IN-TECHNo Het Non-Para Log-Normal Weibull Weibull Weibull2 Factors 2 Factors 3 FactorsWelfare to Welfare Tra<strong>in</strong><strong>in</strong>gBasel<strong>in</strong>e 1 12.951 † 11.769 † 9.916 † 9.736 † 7.437 † 7.511 †Replacement -41.844 † -34.680 † -34.591 † -34.500 † -30.710 † -30.722 †M<strong>in</strong>imum Wage 11.507 † 10.464 † 10.555 † 10.624 † 10.132 † 10.127 †Unemp Rate 1.837 † 0.641 † 0.659 † 0.659 † 0.855 † 0.858 †Welfare Ben. -0.267 -1.202 † -1.165 † -1.169 † -1.058 † -1.046 †Wel. Tr. 3 0.133 0.126JRP 4 0.486 † 0.486 †U.I. Tr. 5 0.123 0.127Welfare to JRPBasel<strong>in</strong>e 1 -16.915 ‡ -12.068 -20.602 † -21.019 † 23.330 † -23.004 †Replacement -2.948 10.486 11.451 11.010 14.679 14.800M<strong>in</strong>imum Wage 24.425 † 20.061 † 20.504 † 20.511 † 20.177 † 19.689 †Unemp Rate 0.114 -2.402 † -2.477 † -2.465 † -2.301 † -2.304 †Welfare Ben. 1.389 0.081 0.093 0.046 0.115 0.095Wel. Tr. 3 0.562 ‡ 0.561 ‡JRP 4 -0.011 -0.039U.I. Tr. 5 0.112 0.109Welfare to UnemploymentBasel<strong>in</strong>e 1 2.275 0.160 -5.840 -6.134 -3.910 -3.511Replacement -30.577 † -16.447 -15.796 -16.035 -19.417 ‡ -18.808 ‡M<strong>in</strong>imum Wage 12.777 16.201 † 16.575 † 16.565 † 16.483 † 15.791 †Unemp Rate 1.538 † -0.399 -0.446 -0.451 -0.568 -0.547Welfare Ben. 1.579 ‡ 0.672 0.682 0.626 0.571 0.456Wel. Tr. 3 0.232 0.210JRP 4 -2.164 ‡ -2.139 ‡U.I. Tr. 5 0.594 0.531Welfare to WorkBasel<strong>in</strong>e 2 -6.268 † 5.172 † -1.084 -1.426 -0.781 -0.902-6.786 † 4.757 † -1.501 -1.836 -1.194 -1.250-7.623 † 4.039 † -2.253 -2.580 -1.941 -1.910Replacement -0.201 -2.715 -2.268 -2.469 -3.464 -2.834M<strong>in</strong>imum Wage 6.019 † -0.608 -0.470 -0.447 -0.345 -0.266Unemp Rate -0.322 † -0.106 -0.127 -0.126 -0.209 -0.219Welfare Ben. -1.107 † -1.214 † -1.204 † -1.231 † -1.272 † -1.342 †Wel. Tr. 3 0.027 0.020JRP 4 -0.454 † -0.436 †U.I. Tr. 5 0.314 0.273Welfare to OLFBasel<strong>in</strong>e 1 -2.676 -1.632 -1.661 -1.858 -1.136 -1.025Replacement -3.865 -6.066 ‡ -6.159 ‡ -5.847 -6.859 ‡ -6.669 ‡M<strong>in</strong>imum Wage -1.026 -1.394 -1.424 -1.268 -1.130 -1.055Unemp Rate 0.396 † 0.500 † 0.484 † 0.508 † 0.382 0.425 ‡Welfare Ben. -0.847 † -0.621 † -0.522 † -0.590 † -0.632 † -0.684 †Wel. Tr. 3 -0.209 -0.242JRP 4 -0.276 -0.233U.I. Tr. 5 0.708 † 0.597 †Table 4. Parameter Estimates – Exits from Welfare1 Exponential hazard.2 Exponential hazard – spl<strong>in</strong>es.3 Dummy <strong>in</strong>dicator for any previous welfare tra<strong>in</strong><strong>in</strong>g.4 Dummy <strong>in</strong>dicator for any previous JRP.5 Dummy <strong>in</strong>dicator for any previous U.I. tra<strong>in</strong><strong>in</strong>g.


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 1965No Het Non-Para Log-Normal Weibull Weibull Weibull2 Factors 2 Factors 3 FactorsUnemployment to WelfareBasel<strong>in</strong>e 2 -20.617 † -28.243 † -29.821 † -29.848 † -29.184 † -29.120 †-17.591 † -25.197 † -26.775 † -26.805 † -26.039 † -25.969 †Replacement 22.900 † 31.891 † 31.726 † 31.632 † 31.541 † 31.616 †M<strong>in</strong>imum Wage -5.551 5.312 † 5.125 † 5.129 † 3.266 3.236Unemp Rate 1.695 † 0.907 ‡ 0.921 ‡ 0.921 ‡ 1.084 † 1.093 †Welfare Ben. 1.620 † 1.289 † 1.313 † 1.314 † 1.403 † 1.401 †Wel. Tr. 3 0.590 † 0.583 †JRP 4 -0.045 -0.046U.I. Tr. 5 2.161 † 2.171 †Unemployment to UnemploymentBasel<strong>in</strong>e 2 -20.463 † -1.743 -7.615 -7.912 -7.524 -7.390-16.030 † 2.695 -3.168 -3.473 -3.016 -2.884Replacement 3.966 -1.913 -1.024 -1.382 -1.547 -1.442M<strong>in</strong>imum Wage 22.232 † 1.669 1.197 1.309 0.371 0.192Unemp Rate 0.901 † 0.947 ‡ 0.981 ‡ 0.973 ‡ 1.042 ‡ 1.065 ‡Welfare Ben. -1.245 † -1.235 † -1.179 † -1.203 † -1.161 † -1.153 †Wel. Tr. 3 0.315 0.338JRP 4 0.305 0.301U.I. Tr. 5 1.477 † 1.473 †Unemployment to Unemployment Tra<strong>in</strong><strong>in</strong>gBasel<strong>in</strong>e 1 -2.325 -6.534 -10.807 -10.988 -10.621 -10.482Replacement -15.630 ‡ -4.039 -4.201 -4.171 -5.389 -5.474M<strong>in</strong>imum Wage 4.588 11.050 † 11.140 † 11.207 † 11.962 † 11.915 †Unemp Rate 1.758 0.329 0.311 0.299 0.202 0.210Welfare Ben. 0.934 0.160 0.192 0.203 0.190 0.203Wel. Tr. 3 -0.398 -0.408U.I. Tr. 5 -0.144 -0.146Unemployment to WorkBasel<strong>in</strong>e 2 -5.570 ‡ 10.517 † 4.550 ‡ 3.985 4.577 ‡ 4.730 ‡-3.400 12.708 † 6.753 † 6.181 † 6.788 † 6.938 †Replacement -3.153 -10.825 † -10.570 † -10.526 † -11.610 † -11.669 †M<strong>in</strong>imum Wage 8.237 † -3.261 † -3.719 † -3.532 † -3.364 † -3.478 †Unemp Rate -0.801 † -0.266 -0.225 -0.235 -0.277 -0.269Welfare Ben. -0.683 † -0.337 -0.299 -0.326 -0.342 -0.330Wel. Tr. 3 -0.385 † -0.368 †JRP 4 0.150 0.156U.I. Tr. 5 0.774 † 0.784 †Unemployment to OLFBasel<strong>in</strong>e 2 -13.698 † -10.051 † -9.952 † -10.042 † -9.426 † -9.302 †-10.723 † -7.069 † -6.986 † -7.079 † -6.418 † -6.293 †Replacement 7.977 † 6.497 ‡ 6.104 ‡ 6.375 ‡ 5.533 5.353M<strong>in</strong>imum Wage 8.652 † 2.008 2.358 2.402 2.015 1.984Unemp Rate -0.054 -0.236 -0.295 -0.305 -0.271 -0.252Welfare Ben. -0.284 -0.390 -0.406 -0.396 -0.378 -0.361Wel. Tr. -0.098 -0.127JRP 0.045 0.061U.I. Tr. 1.399 † 1.353 †Table 4. Cont<strong>in</strong>ued: Parameter Estimates – Exits from Unemployment1 Exponential hazard.2 Exponential hazard – spl<strong>in</strong>es.3 Dummy <strong>in</strong>dicator for any previous welfare tra<strong>in</strong><strong>in</strong>g.4 Dummy <strong>in</strong>dicator for any previous JRP.5 Dummy <strong>in</strong>dicator for any previous U.I. tra<strong>in</strong><strong>in</strong>g.


66 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications20 Will-be-set-by-IN-TECHNo Het Non-Para Log-Normal Weibull Weibull Weibull2 Factors 2 Factors 3 FactorsWork to WelfareBasel<strong>in</strong>e 1 -7.102 † -7.122 † -7.093 † -7.094 † -7.066 † -7.057 †1.825 † 1.829 † 1.823 † 1.823 † 1.815 † 1.812 †Replacement -10.487 † -7.783 † -10.196 † -10.328 † -10.415 † -10.336 †M<strong>in</strong>imum Wage 0.165 1.045 0.230 0.207 0.172 0.175Unemp Rate 1.022 † 0.939 † 1.002 † 1.008 † 1.083 † 1.087 †Welfare Ben. 1.078 † 0.977 † 1.050 † 1.050 † 1.026 † 1.038 †Wel. Tr. 2 0.698 † 0.692 †JRP 3 -1.167 † -1.166 †U.I. Tr. 4 -0.313 -0.306Work to Welfare Tra<strong>in</strong><strong>in</strong>gBasel<strong>in</strong>e 1 -29.322 † 7.320 5.564 5.571 2.880 3.6473.352 † -0.012 -0.019 -0.020 -0.004 -0.006Replacement -35.936 † -43.508 † -43.520 † -43.638 † -34.009 † -35.355 †M<strong>in</strong>imum Wage 25.433 † 26.226 † 26.392 † 26.342 † 18.898 † 18.242 †Unemp Rate -0.107 -0.610 -0.623 -0.614 -0.282 -0.161Welfare Ben. -1.249 † -1.389 ‡ -1.380 ‡ -1.374 ‡ -0.818 -0.629Wel. Tr. 2 1.281 † 1.267 †JRP 3 0.510 † 0.500 †U.I. Tr. 4 -1.067 ‡ -0.996Work to UnemploymentBasel<strong>in</strong>e 1 -6.340 † -6.453 † -6.492 † -6.468 † -6.474 † -6.445 †0.687 † 0.678 † 0.671 † 0.671 † 0.673 † 0.672 †Replacement -2.411 † 7.297 † -0.444 -1.208 † -1.309 † -1.171 †M<strong>in</strong>imum Wage 3.196 † 5.624 † 3.772 † 3.612 † 3.734 † 3.757 †Unemp Rate -0.805 † -0.959 † -0.934 † -0.896 † -0.898 † -0.910 †Welfare Ben. -0.086 -0.436 † -0.228 -0.251 -0.265 ‡ -0.261 ‡Wel. Tr1 2 0.101 0.111Wel. Tr2 5 -0.216 -0.214U.I. Tr1 3 -0.130 -0.125U.I. Tr2 6 1.524 † 1.484 †Work to WorkBasel<strong>in</strong>e 1 -4.758 † -4.722 † -4.683 † -4.687 † -4.698 † -4.713 †1.187 † 1.155 † 1.136 † 1.143 † 1.147 † 1.162 †Replacement -0.583 9.910 † 1.320 † 0.557 0.094 0.123M<strong>in</strong>imum Wage -3.339 † -1.263 ‡ -2.959 † -3.021 † -2.452 † -2.467 †Unemp Rate -0.953 † -1.019 † -1.046 † -1.036 † -1.030 † -1.036 †Welfare Ben. 0.013 -0.285 ‡ -0.122 -0.142 -0.180 -0.159Wel. Tr1 2 -0.248 -0.240Wel. Tr2 5 -0.122 -0.123U.I. Tr1 3 0.014 0.027U.I. Tr2 6 -0.667 -0.716Work to OLFBasel<strong>in</strong>e 1 -6.350 ‡ -6.283 † -6.332 † -6.336 † -6.356 † -6.310 †1.650 † 1.626 † 1.641 † 1.642 † 1.645 † 1.628 †Replacement -0.060 -0.267 -0.480 ‡ -0.319 -1.205 † -1.246 †M<strong>in</strong>imum Wage -3.623 † -3.903 † -3.774 † -3.811 † -2.606 † -2.717 †Unemp Rate -0.974 † -0.916 † -0.911 † -0.908 † -0.915 † -0.877 †Welfare Ben. 0.268 † 0.321 † 0.317 † 0.333 † 0.260 † 0.295 †Wel. Tr1 2 -0.282 † -0.286 †Wel. Tr2 5 -0.572 † -0.586 †U.I. Tr1 3 -0.488 † -0.453 †U.I. Tr2 6 -1.233 -1.237Table 4. (Cont<strong>in</strong>ued)Parameter Estimates – Exits from Employment1 Log-logistic.2 Dummy <strong>in</strong>dicator for any previous welfare tra<strong>in</strong><strong>in</strong>g.3 Dummy <strong>in</strong>dicator for any previous JRP.4 Dummy <strong>in</strong>dicator for any previous U.I. tra<strong>in</strong><strong>in</strong>g.5 Dummy <strong>in</strong>dicator for prior state: welfare tra<strong>in</strong><strong>in</strong>g.6 Dummy <strong>in</strong>dicator for prior state: U.I. tra<strong>in</strong><strong>in</strong>g.


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 2167No Het Non-Para Log-Normal Weibull Weibull Weibull2 Factors 2 Factors 3 FactorsOLF to WelfareBasel<strong>in</strong>e 2 9.050 † -21.852 † -23.272 † -23.247 † -21.271 † -21.201 †8.014 † -22.698 † -24.168 † -24.150 † -22.170 † -22.082 †Replacement -6.865 † 24.985 † 24.469 † 24.301 † 21.054 † 21.196 †M<strong>in</strong>imum Wage -22.989 † 10.913 † 10.664 † 10.630 † 10.589 † 10.576 †Unemp Rate 0.384 † -0.425 † -0.378 † -0.376 † -0.386 † -0.396 †Welfare Ben. 1.759 † -0.002 0.039 0.049 0.038 0.032Wel. Tr. 3 0.261 † 0.251 †JRP 4 -1.236 † -1.229 †U.I. Tr. 5 0.106 0.101OLF to Welfare Tra<strong>in</strong><strong>in</strong>gBasel<strong>in</strong>e 2 17.926 † -6.003 † -10.899 † -10.984 † -8.832 † -8.868 †16.876 † -6.818 † -11.706 † -11.791 † -9.634 † -9.662 †Replacement -64.337 † -29.309 † -25.939 † -25.960 † -25.370 † -26.066 †M<strong>in</strong>imum Wage 23.722 † 34.225 † 36.886 † 36.923 † 30.886 † 31.237 †Unemp Rate 1.865 † 0.547 0.351 0.341 0.940 0.961Welfare Ben. 1.757 † -1.772 ‡ -1.824 † -1.819 † -1.769 ‡ -1.681 ‡Wel. Tr. 3 0.710 † 0.711 †JRP 4 -0.036 -0.087U.I. Tr. 5 0.105 0.201OLF to UnemploymentBasel<strong>in</strong>e 2 17.926 † -6.003 † -10.899 † -10.984 † -8.832 † -8.868 †16.876 † -6.818 † -11.706 † -11.791 † -9.634 † -9.662 †Replacement -18.873 † 10.249 † 9.571 † 8.979 † 4.909 5.430M<strong>in</strong>imum Wage -24.418 † 8.757 † 8.562 † 8.549 † 9.187 † 9.175 †Unemp Rate -1.791 † -2.838 † -2.892 † -2.919 † -2.926 † -2.984 †Welfare Ben. 1.047 † -0.309 -0.321 -0.326 -0.351 -0.359Wel. Tr. 3 -0.913 † -0.906 †JRP 4 -0.046 -0.043U.I. Tr. 5 -0.380 -0.375OLF to WorkBasel<strong>in</strong>e 2 11.804 † -2.367 -8.492 † -8.596 † -6.903 † -6.977 †11.148 † -2.701 ‡ -8.830 † -8.923 † -7.233 † -7.313 †Replacement -6.325 † 12.069 † 12.465 † 11.915 † 9.093 † 9.477 †M<strong>in</strong>imum Wage -22.641 † 3.718 † 3.725 † 3.742 † 3.719 † 3.664 †Unemp Rate -1.950 † -2.861 † -2.896 † -2.934 † -2.938 † -2.957 †Welfare Ben. 0.098 -0.554 † -0.587 † -0.593 † -0.596 † -0.585 †Wel. Tr. 3 -0.008 -0.007JRP 4 -0.612 † -0.618 †U.I. Tr. 5 0.130 0.151Table 4. (Cont<strong>in</strong>ued)Parameter Estimates – Exits from OLF1 Exponential hazard.2 Exponential hazard – spl<strong>in</strong>es.3 Dummy <strong>in</strong>dicator for any previous welfare tra<strong>in</strong><strong>in</strong>g.4 Dummy <strong>in</strong>dicator for any previous JRP.5 Dummy <strong>in</strong>dicator for any previous U.I. tra<strong>in</strong><strong>in</strong>g.


68 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications22 Will-be-set-by-IN-TECHNo Het Non-Para Log-Normal Weibull Weibull Weibull2 Factors 2 Factors 3 FactorsWelfare Tra<strong>in</strong><strong>in</strong>g to WelfareBasel<strong>in</strong>e 1 -4.927 † -4.997 † -4.951 † -4.949 † -4.950 † -5.036 †0.508 † 0.504 † 0.506 † 0.506 † 0.506 † 0.498 †Replacement 14.105 † 16.989 † 14.470 † 14.324 † 14.326 † 15.040 †M<strong>in</strong>imum Wage -16.050 † -14.842 -15.840 † -15.877 † -15.893 † -15.543 †Unemp Rate -0.892 † -1.027 † -0.939 † -0.923 † -0.917 † -0.989 †Welfare Ben. 0.325 0.131 0.287 0.277 0.277 0.158Welfare Tra<strong>in</strong><strong>in</strong>g to WorkBasel<strong>in</strong>e 1 -3.971 † -4.087 † -4.107 † -4.127 † -4.123 † -4.230 †0.277 † 0.277 † 0.270 † 0.268 † 0.268 † 0.262 †Replacement -3.450 † 5.666 † -1.437 -1.959 -2.100 -1.484M<strong>in</strong>imum Wage 3.294 † 7.772 † 3.949 ‡ 3.702 ‡ 3.769 ‡ 3.901 ‡Unemp Rate -0.957 † -1.096 † -0.884 ‡ -0.864 ‡ -0.857 ‡ -0.814Welfare Ben. -0.619 -1.233 † -1.019 ‡ -1.063 ‡ -1.060 ‡ -1.234 †Welfare Tra<strong>in</strong><strong>in</strong>g to OLFBasel<strong>in</strong>e 1 -5.187 † -5.135 † -5.140 † -5.124 † -5.124 † -5.151 †0.403 † 0.405 † 0.401 † 0.403 † 0.403 † 0.404 †Replacement -16.086 † -16.959 † -16.775 † -16.747 † -16.672 † -16.234 †M<strong>in</strong>imum Wage 14.358 † 14.417 † 13.960 † 13.989 † 13.957 † 14.333 †Unemp Rate -0.483 -0.515 -0.430 -0.430 -0.439 -0.486Welfare Ben. -0.219 -0.012 -0.014 0.024 0.021 -0.108JRP to WorkBasel<strong>in</strong>e 2 3.612 5.668 -3.143 -2.889 -3.037 -4.420Replacement -14.331 † -8.461 -5.173 -5.844 -5.767 -5.134M<strong>in</strong>imum Wage 6.240 9.809 11.792 11.488 11.655 11.941 ‡Unemp Rate -0.276 -0.877 -1.024 -1.035 -1.047 -1.104Welfare Ben. -0.581 -1.467 -1.438 -1.731 -1.731 -0.670Unemployment Tra<strong>in</strong><strong>in</strong>g to UnemploymentBasel<strong>in</strong>e 2 5.363 7.502 † 1.457 0.920 1.233 0.822M<strong>in</strong>imum Wage -20.820 † -11.370 † -9.906 † -9.984 † -10.577 † -10.712 †Unemp Rate 0.480 1.571 ‡ 1.452 1.525 1.559 1.544Welfare Ben. -0.084 0.369 0.157 0.231 0.213 0.506Table 4. (Cont<strong>in</strong>ued) Parameter Estimates – Exits from Tra<strong>in</strong><strong>in</strong>g1 Log-logistic.2 Exponential hazard.<strong>in</strong> a recent paper by Fort<strong>in</strong> et al. (2004). In that paper it was found us<strong>in</strong>g a similar samplethat <strong>in</strong>creases <strong>in</strong> the m<strong>in</strong>imum wage rate <strong>in</strong>creased exits from welfare. S<strong>in</strong>ce the transitionstate was not known, this was <strong>in</strong>terpreted as evidence that firms were not constra<strong>in</strong>ed bythe m<strong>in</strong>imum wage rate. Instead, an <strong>in</strong>crease <strong>in</strong> the latter was <strong>in</strong>terpreted as attract<strong>in</strong>g anumber <strong>of</strong> welfare claimants onto the labour market. <strong>The</strong> results reported here provide acompletely different story. Indeed, it appears that <strong>in</strong>creases <strong>in</strong> the m<strong>in</strong>imum wage rate <strong>in</strong>ducewelfare claimants to <strong>in</strong>crease their employability status but does not translate <strong>in</strong>to a largernumber be<strong>in</strong>g employed. Quite to the contrary, the <strong>in</strong>creased transition rates from welfareto unemployment suggest that a number <strong>of</strong> <strong>in</strong>dividuals who were work<strong>in</strong>g while claim<strong>in</strong>gwelfare benefits may have lost their job follow<strong>in</strong>g the <strong>in</strong>crease <strong>in</strong> the m<strong>in</strong>imum wage rate.Increases <strong>in</strong> the unemployment rate translate <strong>in</strong>to smaller transition rates <strong>in</strong>to JRP. This resultis compatible with the fact that welfare claimants may be less motivated to <strong>in</strong>crease theiremployability when job prospects dim<strong>in</strong>ish. Alternatively, firms may also be less <strong>in</strong>cl<strong>in</strong>ed tohire tra<strong>in</strong>ees under the JRP program when the unemployment rate rise.


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 2369As expected, <strong>in</strong>creases <strong>in</strong> welfare benefits decrease the exit rates from welfare. <strong>The</strong> result isstatistically significant <strong>in</strong> transitions towards tra<strong>in</strong><strong>in</strong>g, work <strong>and</strong> OLF states. A similar f<strong>in</strong>d<strong>in</strong>gwas reported by Fort<strong>in</strong> <strong>and</strong> Lacroix <strong>in</strong> the aforementioned paper.Past occurrences <strong>of</strong> welfare tra<strong>in</strong><strong>in</strong>g are generally not very beneficial to the men <strong>in</strong> oursample. <strong>The</strong>y are associated with higher transition rates <strong>in</strong>to welfare tra<strong>in</strong><strong>in</strong>g <strong>and</strong> lower rates<strong>in</strong>to employment <strong>and</strong> OLF. <strong>The</strong> impact is larger for recent occurrences, which suggests thatparticipation <strong>in</strong> such tra<strong>in</strong><strong>in</strong>g programs may convey a bad signal to potential employers. Onthe other h<strong>and</strong>, past occurrences <strong>of</strong> UI tra<strong>in</strong><strong>in</strong>g has little impact on the exits from welfare.4.3.2 Exits from unemployment<strong>The</strong> next panel <strong>of</strong> the table focuses on the transitions from unemployment. Most parameterestimates that are statistically significant have the expected sign a priori. For <strong>in</strong>stance, it isfound that as <strong>in</strong>dividuals get older they are more likely to exit unemployment for employment<strong>and</strong> less for welfare. Similarly, <strong>in</strong>creases <strong>in</strong> the m<strong>in</strong>imum wage rate leads to higher transitionrates <strong>in</strong>to UI tra<strong>in</strong><strong>in</strong>g but lower rates <strong>in</strong>to employment. <strong>The</strong>se results are consistent with thosefound with respect to exits from welfare.Other results presented <strong>in</strong> the panel <strong>in</strong>dicate that unemployed <strong>in</strong>dividuals are more likelyto experience a new unemployment spell or to enter welfare <strong>and</strong> are less likely to enteremployment whenever the unemployment rate <strong>in</strong>creases. Presumably, a number <strong>of</strong> UIclaimants can not f<strong>in</strong>d employment <strong>and</strong> therefore exhaust their benefits. <strong>The</strong> social securitysystem <strong>in</strong> Canada entitles them to welfare benefits upon exhaustion <strong>of</strong> UI benefits. On theother h<strong>and</strong>, <strong>in</strong>creases <strong>in</strong> welfare benefits <strong>in</strong>crease the transition rates <strong>in</strong>to welfare <strong>and</strong> lowerthose <strong>in</strong>to unemployment <strong>and</strong> employment. <strong>The</strong>se results suggest that the transitions towardsemployment are very sensitive to both policy variables, i.e. welfare benefits <strong>and</strong> m<strong>in</strong>imumwages, as well as to the state <strong>of</strong> the economy as proxied by the unemployment rate.A number <strong>of</strong> parameter estimates relat<strong>in</strong>g to the tra<strong>in</strong><strong>in</strong>g dummy variables are statisticallysignificant. Once aga<strong>in</strong>, previous participation <strong>in</strong> welfare tra<strong>in</strong><strong>in</strong>g <strong>in</strong>creases the likelihood <strong>of</strong>enter<strong>in</strong>g welfare upon leav<strong>in</strong>g unemployment <strong>and</strong> decreases that <strong>of</strong> enter<strong>in</strong>g employment. Onthe other h<strong>and</strong>, recent UI tra<strong>in</strong><strong>in</strong>g participation appears to have a conflict<strong>in</strong>g impacts. Indeed,UI claimants are more likely to enter either welfare or UI upon leav<strong>in</strong>g unemployment butare also more likely to enter employment. On the whole, these results are consistent withthose found by Fort<strong>in</strong> et al. (1999b) us<strong>in</strong>g different data <strong>and</strong> econometric estimators <strong>and</strong>are also consistent to some extent with those <strong>of</strong> Gritz (1993) <strong>and</strong> Bonnal et al. (1997). In allthree cases it was found that participation <strong>in</strong> government-sponsored tra<strong>in</strong><strong>in</strong>g programs haddetrimental effects on the labour market experience <strong>of</strong> young men. It has been suggestedthat potential employers may stigmatize participation <strong>in</strong> such tra<strong>in</strong><strong>in</strong>g programs. Becausethese programs are designed to improve the labour market opportunities <strong>of</strong> disadvantagedworkers, participation <strong>in</strong> the later may be taken as a signal <strong>of</strong> unsatisfactory performance <strong>in</strong>previous employment. Our results <strong>in</strong>dicate that tra<strong>in</strong><strong>in</strong>g while on welfare is detrimental tomen, but tra<strong>in</strong><strong>in</strong>g while on unemployment does not convey the same negative signal.4.3.3 Exits from employment<strong>The</strong> next panel <strong>of</strong> the table reports results relat<strong>in</strong>g to transitions from employment. Onceaga<strong>in</strong>, most parameters estimates that are statistically significant have the expected sign.In particular, <strong>in</strong>creases <strong>in</strong> the m<strong>in</strong>imum wage rate is found to <strong>in</strong>crease the likelihood <strong>of</strong>leav<strong>in</strong>g employment for either welfare tra<strong>in</strong><strong>in</strong>g, <strong>and</strong> to dim<strong>in</strong>ish considerably the likelihood <strong>of</strong>


70 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications24 Will-be-set-by-IN-TECHenter<strong>in</strong>g a new job or mov<strong>in</strong>g <strong>in</strong>to welfare. Increases <strong>in</strong> welfare benefits are found to <strong>in</strong>creasethe transitions <strong>in</strong>to welfare <strong>and</strong> to decrease the likelihood <strong>of</strong> enter<strong>in</strong>g welfare tra<strong>in</strong><strong>in</strong>g.<strong>The</strong> parameter estimates associated with the unemployment rate has the expected sign exceptperhaps with respect to transitions between employment <strong>and</strong> unemployment. Indeed, theparameter estimate implies that whenever the unemployment rate <strong>in</strong>creases, workers are lesslikely to leave employment to enter unemployment. <strong>The</strong>re are several potential explanationsfor this result. First, it may well be that when the labour market deteriorates, workers wholoose their job have difficulty qualify for UI benefits. Recall from Table 1 that the unconditionalmean job duration is approximately 18 weeks, which is roughly equal to the qualify<strong>in</strong>g period.<strong>The</strong>y are thus more likely to turn to welfare, as <strong>in</strong>dicated <strong>in</strong> the first column <strong>of</strong> the panel.Second, the deterioration <strong>of</strong> the labour market may <strong>in</strong>duce some to hold on to their currentjob longer. <strong>The</strong> fact that all the parameter estimates are negative, except for welfare, isconsistent with this possibility. F<strong>in</strong>ally, <strong>in</strong>creases <strong>in</strong> welfare benefits <strong>in</strong>crease the transitionsfrom employment to welfare, as expected.<strong>The</strong> tra<strong>in</strong><strong>in</strong>g variables show <strong>in</strong>terest<strong>in</strong>g results. For <strong>in</strong>stance, those who have participated<strong>in</strong> welfare tra<strong>in</strong><strong>in</strong>g are more likely to enter either welfare or welfare tra<strong>in</strong><strong>in</strong>g upon exit<strong>in</strong>gemployment, although recent participation makes them less likely to enter welfare anew.Likewise, participation <strong>in</strong> welfare tra<strong>in</strong><strong>in</strong>g translates <strong>in</strong>to less employment–employmenttransitions. Those who were <strong>in</strong> UI tra<strong>in</strong><strong>in</strong>g just prior to their current employment spell aremuch more likely to return to UI upon leav<strong>in</strong>g employment <strong>and</strong> much less likely to experiencean employment-employment transition. <strong>The</strong> likelihood <strong>of</strong> enter<strong>in</strong>g the OLF state follow<strong>in</strong>gemployment decreases substantially if the <strong>in</strong>dividual experienced either UI or welfare tra<strong>in</strong><strong>in</strong>g<strong>in</strong> the past.4.3.4 Exits from OLF<strong>The</strong> results presented <strong>in</strong> the follow<strong>in</strong>g panel relate to the OLF state. Recall that thisstate <strong>in</strong>cludes <strong>in</strong>dividuals that are truly out <strong>of</strong> the labour force but may also <strong>in</strong>cludefull-time students <strong>and</strong> non-entitled unemployed workers. Caution must thus be exercised<strong>in</strong> <strong>in</strong>terpret<strong>in</strong>g these results.Surpris<strong>in</strong>gly many parameter estimates turn out to be statistically significant. Of particular<strong>in</strong>terest, transitions from OLF to employment appear to be quite sensitive to the economicenvironment. Transitions to employment are thus less when the m<strong>in</strong>imum wage rate orthe welfare benefits <strong>in</strong>crease. Similarly, the transitions <strong>in</strong>to welfare <strong>and</strong> welfare tra<strong>in</strong><strong>in</strong>g arerelatively sensitive to policy variables. As <strong>in</strong> previous panels, the transitions <strong>in</strong>to welfaretra<strong>in</strong><strong>in</strong>g are more likely for those who have previously experienced such tra<strong>in</strong><strong>in</strong>g.For the sake <strong>of</strong> brevity, the estimation results for tra<strong>in</strong><strong>in</strong>g programs are not presented butare available upon request. <strong>The</strong> econometric model generally does a poorer job at predict<strong>in</strong>gtransitions from the tra<strong>in</strong><strong>in</strong>g programs compared to those for other states <strong>of</strong> the labour market,although a number <strong>of</strong> parameter estimates are statistically significant.4.3.5 Unobserved heterogeneityTable 5 reports the value <strong>of</strong> the likelihood function for a number <strong>of</strong> different specificationsas well as the parameter estimates related to the unobserved heterogeneity <strong>of</strong> each. As


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 2571No Het Non-Para Log-Normal Weibull Weibull Weibull2 Factors 2 Factors 3 FactorsProbability 0.614 †ω 1 -1.866 †ω 2 -2.364 †b 2 -0.116 -0.221 -0.365 -0.184 -2.980 †b 3 3.757 † 7.781 † 8.304 † 8.209 † 8.173 †b 4 2.337 † 5.455 † 6.201 † 6.037 † 8.879 †b 5 1.323 0.447 0.244 -1.091 -1.691b 6 2.585 † 5.493 † 6.432 † 6.168 † 7.722 †b 7 -1.180 † -2.501 † -2.938 † -2.876 † -4.902 †b 1 ′ 2.768 †b 2 ′ 3.093 †b 3 ′ -7.131 †b 4 ′ 0.333b 5 ′ -8.563 †b 6 ′ -0.437b 7 ′ 0.738 †μ -1.629 †σ -0.566 †λ 9.493 † 9.057 † 14.685 †γ 0.163 † 0.147 † 0.216 †Log-likelihood -150668.6 -149774.2 -149847.8 -149818.9 -149474.8 149422.6Table 5. Heterogeneity Parameters† Statistically significant at 5%‡ Statistically significant at 10%mentioned earlier, the slope parameters <strong>of</strong> these specifications are sufficiently similar to omitthem from the tables. 16<strong>The</strong> first specification <strong>of</strong> the table does not control for unobserved heterogeneity <strong>and</strong> is thusa special case <strong>of</strong> all the other specifications. A simple likelihood-ratio test strongly rejectsthe first specification <strong>in</strong> favour <strong>of</strong> any specification that <strong>in</strong>cludes unobserved heterogeneity.<strong>The</strong> second specification is a st<strong>and</strong>ard non-parametric two-factor load<strong>in</strong>g model <strong>and</strong> waspresented <strong>in</strong> equation (4). Most parameter estimates are statistically significant, except forb 2 <strong>and</strong> b 5 which concern transitions <strong>in</strong>to welfare tra<strong>in</strong><strong>in</strong>g programs <strong>and</strong> UI tra<strong>in</strong><strong>in</strong>g programs,respectively. Accord<strong>in</strong>gly, these estimates suggest there is little, if any, selectivity <strong>in</strong>to thesetwo tra<strong>in</strong><strong>in</strong>g programs.<strong>The</strong> third column <strong>of</strong> the table reports the parameter estimates <strong>of</strong> a parametric two-factorload<strong>in</strong>g model. As was mentioned earlier, the weibull distribution function was preferredover all other distribution functions that were <strong>in</strong>vestigated. Notice that as <strong>in</strong> thenon-parametric specification, only b 2 <strong>and</strong> b 5 are not statistically significant. <strong>The</strong> last twol<strong>in</strong>es <strong>of</strong> the table report the parameter estimates <strong>of</strong> the weibull distribution, λ <strong>and</strong> γ. 17F<strong>in</strong>ally, the last column <strong>of</strong> the table presents the parameter estimates <strong>of</strong> the three-factor16 Bonnal et al. (1997) also found the slope parameters to be relatively <strong>in</strong>sensitive to the distributionalassumptions <strong>of</strong> the unobserved heterogeneity variables. In their work, they compare a two-factorload<strong>in</strong>g model with a f<strong>in</strong>ite number <strong>of</strong> po<strong>in</strong>ts <strong>of</strong> support with a s<strong>in</strong>gle-factor load<strong>in</strong>g model that drawsheterogeneity terms from an i.i.d. IN (0, 1) distribution. <strong>The</strong> <strong>in</strong>sensitivity <strong>of</strong> the slope parameters tothe distributional assumption is consistent with the results <strong>of</strong> Heckman & S<strong>in</strong>ger (1984) us<strong>in</strong>g s<strong>in</strong>gledurations data.17 <strong>The</strong> weibull distribution function <strong>of</strong> a r<strong>and</strong>om variable x is given by F(x) =1 − exp [−λx γ ].


72 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications26 Will-be-set-by-IN-TECHWelfare Welf. Tr. JRP UI UI Tr. Employ. OLFTWO-FACTOR LOADING MODEL –NON-PARAMETRICWelfare 1.000 -0.157 0.982 0.954 0.875 0.962 -0.850(0.195) (0.010) (0.010) (0.236) (0.007) (0.023)Wel. Tr. 1.000 0.035 0.145 0.340 0.118 0.653(0.200) (0.197) (0.495) (0.196) (0.150)JRP 1.000 0.994 0.952 0.997 -0.734(0.006) (0.151) (0.004) (0.051)UI 1.000 0.980 1.000 -0.654(0.098) (0.001) (0.052)UI Tr. 1.000 0.974 -0.489(0.111) (0.430)Emplo. 1.000 -0.675(0.048)TWO-FACTOR LOADING MODEL –LOG-NORMAL DISTRIBUTIONWelfare 1.000 -0.216 0.992 0.984 0.408 0.984 -0.929(0.263) (0.004) (0.004) (1.680) (0.004) (0.015)Wel. Tr. 1.000 -0.089 -0.036 0.803 -0.037 0.563(0.271) (0.272) (1.108) (0.272) (0.221)JRP 1.000 0.999 0.521 0.999 -0.874(0.002) (1.571) (0.002) (0.029)U.I. 1.000 0.566 1.000 -0.846(1.516) (0.000) (0.032)UI Tr. 1.000 0.565 -0.040(1.518) (1.841)Emplo. 1.000 -0.847(0.031)Table 6. Correlations Between Heterogeneity Variables(St<strong>and</strong>ard Errors <strong>in</strong> Parentheses)load<strong>in</strong>g model (see equation(6)), whose slope parameters were presented <strong>in</strong> Table 4. A simplelog-likelihood ratio test rejects the two-factor load<strong>in</strong>g model <strong>in</strong> favour <strong>of</strong> the three-factorload<strong>in</strong>g model. Contrary to the two previous specifications, b 2 is now highly statisticallysignificant. Furthermore, nearly all the b ′ j parameters are statistically significant. This suggeststhat the richer specification may be better suited to uncover selection <strong>in</strong>to the different states.In order to <strong>in</strong>vestigate this issue, Table 6 reports the correlation coefficients between theheterogeneity variables that are implicit <strong>in</strong> each specification along with their st<strong>and</strong>ard errors.<strong>The</strong> first two panels focus on the non-parametric <strong>and</strong> the weibull two-factor load<strong>in</strong>g models.Recall that these correlation coefficients <strong>in</strong>dicate the extent to which one is as likely to enterstate j as state k upon leav<strong>in</strong>g any given state. While a number <strong>of</strong> coefficients are similar acrossboth panels, there are significant differences. To start with, the first l<strong>in</strong>e <strong>of</strong> each panel showsthat high transition rates <strong>in</strong>to welfare are associated with lower transition rates <strong>in</strong>to welfaretra<strong>in</strong><strong>in</strong>g <strong>and</strong> higher rates <strong>in</strong>to unemployment. On the other h<strong>and</strong>, both panels disagreesignificantly with respect to the correlations between welfare tra<strong>in</strong><strong>in</strong>g <strong>and</strong> the other states, aswell as between JRP <strong>and</strong> other states. <strong>The</strong> non-parametric model implies that welfare tra<strong>in</strong><strong>in</strong>g<strong>and</strong> UI tra<strong>in</strong><strong>in</strong>g are positively correlated whereas the opposite holds true <strong>in</strong> the parametricmodel. Similarly, the top panel <strong>in</strong>dicates that JRP is positively correlated to all other states onthe labour market, contrary to the parametric model which shows no such relations.<strong>The</strong> last panel <strong>of</strong> Table 6 focuses on the correlation coefficients implicit <strong>in</strong> the three-factorload<strong>in</strong>g model. Each section <strong>of</strong> the panel is related to the correlation coefficients <strong>in</strong> equations


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 2773Welfare Welf. Tr. JRP UI UI Tr. Employ. OLFTWO-FACTOR LOADING MODELWEIBULL DISTRIBUTION -NO DUMMY INDICATORSWelfare 1.000 -0.343 0.993 0.987 0.237 0.988 -0.947(0.266) (0.004) (0.004) (2.413) (0.003) (0.012)Wel. Tr. 1.000 -0.228 -0.189 0.832 -0.195 0.627(0.278) (0.281) (1.390) (0.280) (0.218)JRP 1.000 0.999 0.351 0.999 -0.901(0.001) (2.325) (0.001) (0.026)U.I. 1.000 0.388 1.000 -0.883(2.288) (0.027)UI Tr. 1.000 0.383 0.089(2.294) (2.475)Emplo. 1.000 -0.886(0.026)TWO-FACTOR LOADING MODELWEIBULL DISTRIBUTION -WITH DUMMY INDICATORSWelfare 1.000 -0.181 0.993 0.987 -0.737 0.987 -0.945(0.337) (0.004) (0.004) (0.943) (0.003) (0.013)Wel. Tr. 1.000 -0.061 -0.018 0.798 -0.021 0.494(0.341) (0.344) (0.872) (0.344) (0.296)JRP 1.000 0.999 -0.650 0.999 -0.898(0.002) (1.062) (0.001) (0.027)U.I. 1.000 -0.617 1.000 -0.878(1.098) (0.000) (0.028)UI Tr. 1.000 -0.619 0.918(1.096) (0.552)Emplo. 1.000 -0.880(0.027)Table 6. (Cont<strong>in</strong>ued)Correlations Between Heterogeneity Variables(St<strong>and</strong>ard Errors <strong>in</strong> Parentheses)(7)–(9), respectively. Hence, the first section has the same <strong>in</strong>terpretation as the correlations <strong>of</strong>the previous panels. <strong>The</strong> correlation coefficients reported <strong>in</strong> this section differ considerablyfrom the previous ones. Accord<strong>in</strong>g to the estimates, it now appears that there is considerableselectivity <strong>in</strong>to welfare tra<strong>in</strong><strong>in</strong>g as well as <strong>in</strong> JRP. Indeed, those who are more likely toparticipate <strong>in</strong> the former are also more likely to tra<strong>in</strong> under JRP <strong>and</strong> to f<strong>in</strong>d employment.On the other h<strong>and</strong>, higher transition rates <strong>in</strong>to JRP or welfare tra<strong>in</strong><strong>in</strong>g is now associated withlower transition rates <strong>in</strong>to UI <strong>and</strong> UI tra<strong>in</strong><strong>in</strong>g. This is <strong>in</strong> stark contrast with the previousresults. Other correlation coefficients are relatively similar to the previous ones.<strong>The</strong> second section <strong>of</strong> the panel reports the correlation coefficients with respect to the orig<strong>in</strong>states. Large heterogeneity values <strong>in</strong> the orig<strong>in</strong> state translate <strong>in</strong>to short spell durations.Consequently, the correlations reflect the frequency with which <strong>in</strong>dividuals transit across thevarious states. <strong>The</strong> estimates show that <strong>in</strong>dividuals who are more likely to have long welfarespells are also likely to have short employment spells. <strong>The</strong> same holds with respect to welfaretra<strong>in</strong><strong>in</strong>g <strong>and</strong> employment, as well as JRP <strong>and</strong> employment. Those who are more likely to haveshort unemployment spells are more likely to have long JRP, welfare tra<strong>in</strong><strong>in</strong>g or UI tra<strong>in</strong><strong>in</strong>gspells.


74 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications28 Will-be-set-by-IN-TECHWelfare Welf. Tr. JRP UI UI Tr. Employ. OLFCORRELATION BETWEEN DESTINATION STATESWelfare 1.000 -0.948 0.993 0.994 -0.861 0.992 -0.980(0.026) (0.006) (0.002) (0.568) (0.002) (0.007)Wel. Tr. 1.000 -0.902 -0.906 0.978 -0.899 0.992(0.042) (0.038) (0.232) (0.040) (0.007)JRP 1.000 0.998 -0.792 0.998 -0.948(0.001) (0.682) (0.000) (0.020)UI 1.000 -0.798 0.999 -0.951(0.672) (0.001) (0.014)UI Tr. 1.000 -0.788 0.945(0.687) (0.363)Emplo. 1.000 -0.946(0.015)CORRELATION BETWEEN ORIGIN STATESWelfare 1.000 0.951 -0.990 0.316 -0.993 -0.401 0.594(0.027) (0.006) (0.756) (0.006) (0.369) (0.197)Wel. Tr. 1.000 -0.900 0.592 -0.909 -0.099 0.812(0.046) (0.622) (0.045) (0.374) (0.123)JRP 1.000 -0.181 1.000 0.524 -0.476(0.784) (0.002) (0.346) (0.223)U.I. 1.000 -0.204 0.743 0.951(0.782) (0.467) (0.225)UI Tr. 1.000 0.504 -0.496(0.350) (0.221)Emplo. 1.000 0.500(0.310)CORRELATION BETWEEN ORIGIN-DESTINATION STATESWelfare 1.000 0.951 -0.990 0.316 -0.993 -0.401 0.594(0.027) (0.006) (0.756) (0.006) (0.369) (0.197)Wel. Tr. -0.948 -0.902 0.939 -0.299 0.942 0.380 -0.563(0.026) (0.044) (0.028) (0.720) (0.028) (0.345) (0.197)JRP 0.993 0.944 -0.983 0.313 -0.986 -0.398 0.589(0.006) (0.028) (0.009) (0.751) (0.009) (0.367) (0.196)UI 0.994 0.946 -0.984 0.314 -0.987 -0.398 0.590(0.002) (0.028) (0.007) (0.751) (0.007) (0.367) (0.196)UI Tr. -0.861 -0.819 0.852 -0.272 0.855 0.345 -0.511(0.568) (0.544) (0.563) (0.725) (0.565) (0.367) (0.395)Emplo. 0.992 0.944 -0.982 0.313 -0.985 -0.397 0.589(0.002) (0.028) (0.007) (0.750) (0.007) (0.366) (0.196)OLF -0.980 -0.932 0.970 -0.309 0.973 0.392 -0.582(0.007) (0.031) (0.010) (0.742) (0.010) (0.360) (0.196)Table 6. (Cont<strong>in</strong>ued) Correlations Between Heterogeneity VariablesThree-Factor Load<strong>in</strong>g Model(St<strong>and</strong>ard Errors <strong>in</strong> Parentheses)


<strong>The</strong> Impact <strong>of</strong> Government-SponsoredTra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men<strong>The</strong> Impact <strong>of</strong> Government-Sponsored Tra<strong>in</strong><strong>in</strong>g Programs on the Labor Market Transitions <strong>of</strong> Disadvantaged Men 2975<strong>The</strong> last section <strong>of</strong> the panel reports the implicit correlations between the orig<strong>in</strong> <strong>and</strong> thedest<strong>in</strong>ation states. Note that the correlation matrix need not be symmetric nor does thediagonal need be equal to unity. On the other h<strong>and</strong>, the restrictions that were imposed toachieve identification <strong>of</strong> the load<strong>in</strong>g parameters imply that the first row <strong>of</strong> the matrix is equalto the first row <strong>of</strong> the matrix <strong>of</strong> the middle section.For the sake <strong>of</strong> brevity we will focus our attention on the most <strong>in</strong>terest<strong>in</strong>g correlations. <strong>The</strong>estimates suggest that those who are likely to have short welfare tra<strong>in</strong><strong>in</strong>g spells are also lesslikely to transit through welfare or JRP <strong>and</strong> more likely to enter employment (row 2). Similarly,row 3 <strong>in</strong>dicates that <strong>in</strong>dividuals who are likely to have short JRP spells are less likely to returnto either welfare or welfare tra<strong>in</strong><strong>in</strong>g <strong>in</strong> the future, <strong>and</strong> much more likely to enter employment.F<strong>in</strong>ally, those who have short UI tra<strong>in</strong><strong>in</strong>g spells (row 5) have higher transitions rates <strong>in</strong>towelfare <strong>and</strong> welfare tra<strong>in</strong><strong>in</strong>g, <strong>and</strong> lower transitions rates <strong>in</strong>to employment.<strong>The</strong>se correlations suggest there is considerable selectivity <strong>in</strong>to the tra<strong>in</strong><strong>in</strong>g programs.Furthermore, they show that those who are selected <strong>in</strong>to welfare <strong>and</strong> JRP tra<strong>in</strong><strong>in</strong>g programsappear to be different from those who participate <strong>in</strong> UI tra<strong>in</strong><strong>in</strong>g programs. As a matter <strong>of</strong> fact,all the correlation coefficients <strong>of</strong> the last section <strong>of</strong> the panel perta<strong>in</strong><strong>in</strong>g to UI tra<strong>in</strong><strong>in</strong>g havethe opposite sign to those <strong>of</strong> welfare <strong>and</strong> JRP tra<strong>in</strong><strong>in</strong>g. Consider, for example, those who haveunexpectedly long UI tra<strong>in</strong><strong>in</strong>g spells <strong>and</strong> those who have unexpectedly short welfare tra<strong>in</strong><strong>in</strong>gor JRP spells. Accord<strong>in</strong>g to the last section <strong>of</strong> the panel, all these <strong>in</strong>dividuals are more likelyto move <strong>in</strong>to employment upon exit<strong>in</strong>g their respective spells than average. Yet, the middlesection <strong>in</strong>dicates that only those on welfare tra<strong>in</strong><strong>in</strong>g or JRP are likely to have long employmentspells. Those who were on UI tra<strong>in</strong><strong>in</strong>g are more likely to have short employment spells.That those who are likely to have short JRP or welfare tra<strong>in</strong><strong>in</strong>g spells are more likely toexperiment long employment spells may be somewhat surpris<strong>in</strong>g. In fact, when study<strong>in</strong>g theimpact <strong>of</strong> the Youth Tra<strong>in</strong><strong>in</strong>g Scheme <strong>in</strong> the UK, Mealli et al. (1996) <strong>and</strong> Mealli & Pudney (2003)conjectured that early program term<strong>in</strong>ation may result from more <strong>in</strong>tensive search stemm<strong>in</strong>gfrom better than average motivation. Hence, early term<strong>in</strong>ation may be associated with ahigher probability <strong>of</strong> transition <strong>in</strong>to employment <strong>and</strong> longer employment spells. Conversely,if failure to complete the full term is a consequence <strong>of</strong> low ability <strong>and</strong> motivation, it may beassociated with poorer employment outcomes. Although we have no <strong>in</strong>formation regard<strong>in</strong>gprogram completion, our results are consistent with the first possibility, whereas those <strong>of</strong>Mealli et al. (1996) were consistent with the second possibility.5. Conclusion<strong>The</strong> analysis has focused on an exam<strong>in</strong>ation <strong>of</strong> the impact <strong>of</strong> government-sponsored tra<strong>in</strong><strong>in</strong>gprograms aimed at disadvantaged male youths on their labour market transitions. We haveelected to concentrate our attention on this group s<strong>in</strong>ce they have fared relatively poorly onthe labour market over the past decade <strong>in</strong> Canada by all accounts. <strong>The</strong> richness <strong>of</strong> the dataat our disposal has allowed us to recreate very detailed <strong>in</strong>dividual histories over a relativelylong period. As many as seven dist<strong>in</strong>ct states on the labour market could be identified <strong>in</strong> thedata.This study has applied a cont<strong>in</strong>uous time duration model to estimate the density <strong>of</strong> durationtimes <strong>in</strong> these seven states, controll<strong>in</strong>g for the endogeneity <strong>of</strong> an <strong>in</strong>dividual’s tra<strong>in</strong><strong>in</strong>g status.Most previous studies have used survey or adm<strong>in</strong>istrative data that were less amenableto the k<strong>in</strong>d <strong>of</strong> analysis performed <strong>in</strong> this chapter. Depend<strong>in</strong>g on the nature <strong>of</strong> the data,


76 Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications30 Will-be-set-by-IN-TECHcomplex adjustments to the model were <strong>of</strong>ten required to account for potential problemsrelated to stock sampl<strong>in</strong>g <strong>and</strong> <strong>in</strong>itial conditions. Fortunately, we were able to avoid thesedifficulties by recreat<strong>in</strong>g each <strong>in</strong>dividual’s history as early as age 16, the legal school-leav<strong>in</strong>gage <strong>in</strong> Canada. Consequently, the <strong>in</strong>itial state can be safely considered exogenous, <strong>and</strong> thesubsequent duration times void <strong>of</strong> any form <strong>of</strong> bias.<strong>The</strong>re is no consensus <strong>in</strong> the literature concern<strong>in</strong>g the appropriate treatment <strong>of</strong> unobservedheterogeneity <strong>in</strong> multi-states multi-episodes duration models. When few states areconsidered, two-factor load<strong>in</strong>g models with a f<strong>in</strong>ite set <strong>of</strong> po<strong>in</strong>ts <strong>of</strong> support have becomerelatively st<strong>and</strong>ard. When the analysis focuses on more states, factor load<strong>in</strong>g models require alarge number <strong>of</strong> parameters to be flexible or become relatively restrictive if a parsimoniousspecification is used. In this chapter we have chosen to <strong>in</strong>vestigate the sensitivity <strong>of</strong> theparameter estimates by compar<strong>in</strong>g a typical non-parametric specification <strong>and</strong> a series <strong>of</strong>parametric two-factor load<strong>in</strong>g models. <strong>The</strong>se models implicitly assume that the <strong>in</strong>tensity<strong>of</strong> transitions are related to the state <strong>of</strong> dest<strong>in</strong>ation. We have also estimated a parametricthree-factor load<strong>in</strong>g model. <strong>The</strong> novelty <strong>of</strong> this specification lies <strong>in</strong> the fact that the <strong>in</strong>tensities<strong>of</strong> transitions are related to both to the state <strong>of</strong> dest<strong>in</strong>ation <strong>and</strong> the state <strong>of</strong> orig<strong>in</strong>.<strong>The</strong> estimation <strong>of</strong> the model yields a number <strong>of</strong> <strong>in</strong>terest<strong>in</strong>g results. As found <strong>in</strong> previousstudies, unobserved heterogeneity appears to play an important role <strong>in</strong> determ<strong>in</strong><strong>in</strong>g whoselects or gets selected <strong>in</strong> tra<strong>in</strong><strong>in</strong>g programs. On the other h<strong>and</strong>, the slope <strong>and</strong> basel<strong>in</strong>e hazardparameter estimates are not very sensitive to the choice <strong>of</strong> a particular distribution functionfor the unobserved heterogeneity variables. <strong>The</strong> two-factor load<strong>in</strong>g models, either parametricor non-parametric, yield essentially the same results as the three-factor load<strong>in</strong>g model. <strong>The</strong>seshow that the duration times <strong>in</strong> any <strong>of</strong> the seven states considered are sensitive to variations<strong>in</strong> program parameters such as welfare benefits, policy variables such as the m<strong>in</strong>imum wagerate, <strong>and</strong> <strong>in</strong> the economic environment as proxied by the unemployment rate. Nearly all theparameter estimates have the expected sign when statistically significant.<strong>The</strong> results perta<strong>in</strong><strong>in</strong>g to the impact <strong>of</strong> the welfare tra<strong>in</strong><strong>in</strong>g programs <strong>and</strong> JRP are similarto those found earlier by Gritz (1993), Bonnal et al. (1997) <strong>and</strong> Fort<strong>in</strong> et al. (1999a). Inessence, young, poorly educated males who participate <strong>in</strong> these programs do not fair as wellon the labour market compared to non-participants, even after controll<strong>in</strong>g for unobservedheterogeneity. On the other h<strong>and</strong>, participation <strong>in</strong> tra<strong>in</strong><strong>in</strong>g programs while on unemployment<strong>in</strong>surance provides them some benefits <strong>in</strong> the form <strong>of</strong> <strong>in</strong>creased transitions <strong>in</strong>to employment.6. 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Returns to Education <strong>and</strong> Experience With<strong>in</strong> theEU: An Instrumental Variable Approach forPanel DataInmaculada García-Ma<strong>in</strong>ar <strong>and</strong> Víctor M. Montuenga-GómezUniversity <strong>of</strong> ZaragozaSpa<strong>in</strong>51. IntroductionEstimat<strong>in</strong>g the returns to education <strong>and</strong> experience has been a topic for labour economistsfor decades, with a significant volume <strong>of</strong> research be<strong>in</strong>g devoted to apprais<strong>in</strong>g the causaleffect <strong>of</strong> school<strong>in</strong>g on earn<strong>in</strong>gs. One central <strong>in</strong>terest when estimat<strong>in</strong>g these returns has beento study whether differences exist across several demographic sectors; essentially,dist<strong>in</strong>guish<strong>in</strong>g between males <strong>and</strong> females, whites <strong>and</strong> non-whites, or natives <strong>and</strong>immigrants, to assess the possibility <strong>of</strong> wage discrim<strong>in</strong>ation, <strong>and</strong> to compute the extent <strong>of</strong>the wage gap between the groups (Harmon et al., 2003).A rapidly grow<strong>in</strong>g literature exam<strong>in</strong>es differences <strong>in</strong> the return to education, dist<strong>in</strong>guish<strong>in</strong>gbetween the self-employed <strong>and</strong> wage earners (Evans & Leighton, 1989; Hamilton, 2000;Lazear & Moore, 1984; Rees & Shah, 1986). Fundamentally, these studies have set out notonly to <strong>in</strong>vestigate earn<strong>in</strong>g differentials between the two employment groups per se, but alsoto test compet<strong>in</strong>g views about the relationship between earn<strong>in</strong>gs <strong>and</strong> education, on the basisthat these groups are subject to different economic <strong>in</strong>centives. In this context, the selfemployedcan be used as a control group to dist<strong>in</strong>guish between human capital <strong>and</strong> sort<strong>in</strong>gmodels <strong>of</strong> wage determ<strong>in</strong>ation, assum<strong>in</strong>g that signal<strong>in</strong>g or screen<strong>in</strong>g functions are much lessrelevant for the self-employed (Riley, 1979; Wolp<strong>in</strong>, 1977). Returns to experience for the selfemployedhave also been estimated aga<strong>in</strong>st those for wage earners, <strong>in</strong> order to test differenttheories <strong>of</strong> the labor market, such as those <strong>of</strong> agency <strong>and</strong> risk hypotheses, aga<strong>in</strong>st thelearn<strong>in</strong>g <strong>and</strong> match<strong>in</strong>g models, <strong>and</strong> aga<strong>in</strong>st the compensat<strong>in</strong>g differentials premises, forexample. Thus, so long as the self-employed have fewer <strong>in</strong>centives to shirk on the job, or toquit it, they should exhibit flatter earn<strong>in</strong>gs-experience pr<strong>of</strong>iles, s<strong>in</strong>ce wage earners obta<strong>in</strong>higher earn<strong>in</strong>gs than the self-employed as they grow older (Salop <strong>and</strong> Salop, 1976).In this chapter, we set out to estimate the returns to education <strong>and</strong> to experience for both theself-employed <strong>and</strong> wage earners, with our aim be<strong>in</strong>g to address some <strong>of</strong> the issues raisedabove. In do<strong>in</strong>g so, we provide evidence <strong>of</strong> such returns for three EU countries, namelyGermany, Italy <strong>and</strong> the UK, us<strong>in</strong>g panel data <strong>in</strong>formation. Exam<strong>in</strong><strong>in</strong>g cross-country data ishelpful <strong>in</strong> identify<strong>in</strong>g common features that are not considered <strong>in</strong> a s<strong>in</strong>gle-country analysis.Moreover, these countries cover a wide range <strong>of</strong> variation across Europe. Germanyrepresents those countries with self-employment rates well below the EU average; Italy is anexample <strong>of</strong> those Southern <strong>and</strong> peripheral countries with self-employment rates over 20%,


80Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications<strong>and</strong> the UK st<strong>and</strong>s for those countries exhibit<strong>in</strong>g the average. Table 1 shows the 20-yearevolution <strong>of</strong> the self-employment rate with<strong>in</strong> the EU-15.1987 1995 2000 2007Austria - 10.8 10.5 14.4Belgium 15.3 15.4 13.6 12.8Denmark 9.2 8.4 8.0 8.9F<strong>in</strong>l<strong>and</strong> - 14.3 12.6 12.6France 12.7 11.6 10.0 9.0Germany 9.1 9.4 9.7 12.0Greece 35.4 33.8 31.3 35.9Irel<strong>and</strong> 21.8 20.8 16.5 16.8Italy 24.4 24.5 23.6 26.4Luxembourg 9.2 10.0 8.7 6.1Netherl<strong>and</strong>s 10.1 11.5 10.0 12.4Portugal 27.2 25.8 20.2 24.2Spa<strong>in</strong> 23.5 21.8 18.0 17.7Sweden - 11.3 9.8 10.6United K<strong>in</strong>gdom 12.5 13.0 10.9 13.8EU15 15.9 15.0 13.6 15.6Table 1. Self-employment rates (Eurostat Labour Force Survey). Note: Percentage <strong>of</strong> selfemployedpersons over total employed.Us<strong>in</strong>g a homogeneous database, we <strong>in</strong>vestigate whether differences exist <strong>in</strong> the pr<strong>of</strong>itability<strong>of</strong> school<strong>in</strong>g <strong>and</strong> experience, both between the two employment statuses, <strong>and</strong> across thethree sample countries. <strong>The</strong> database used <strong>in</strong> this work has been obta<strong>in</strong>ed from theEuropean Community Household Panel (ECHP), from 1994 to 2000, which providesabundant <strong>in</strong>formation about the personal <strong>and</strong> labour characteristics <strong>of</strong> <strong>in</strong>dividuals, <strong>and</strong> hasthe advantage that this <strong>in</strong>formation is homogeneous across the sample countries, given thatthe questionnaire is the same <strong>and</strong> the collection process is coord<strong>in</strong>ated by the StatisticalOffice <strong>of</strong> the European Community (EUROSTAT). Additionally, the application <strong>of</strong> paneldata techniques <strong>of</strong>fers some clear advantages over the traditional cross-sectionalapproaches. First, <strong>in</strong>dividual unobserved heterogeneity is controlled for. Second, biasesaris<strong>in</strong>g from aggregation, selectivity, measurement error, <strong>and</strong> endogeneity can be dealt with<strong>in</strong> an appropriate form. Third, dynamic behavior, such as the movements <strong>in</strong>to <strong>and</strong> out <strong>of</strong>self-employment, may be explicitly accounted for.<strong>The</strong> two usual estimators used <strong>in</strong> panel data, that is to say fixed <strong>and</strong> r<strong>and</strong>om effects, are,however, <strong>in</strong>adequate <strong>in</strong> this sett<strong>in</strong>g if the objective is to obta<strong>in</strong> consistent <strong>and</strong> efficientmeasures <strong>of</strong> the pr<strong>of</strong>itability <strong>of</strong> education <strong>and</strong> experience. Thus, the presence <strong>of</strong> time<strong>in</strong>variant<strong>and</strong> possibly endogenous regressors (e.g. education), would make it impossible toestimate their associated parameters when a time or mean-differenc<strong>in</strong>g approach, i.e. thefixed effects, is applied. Additionally, the probable correlation between these time-<strong>in</strong>variantregressors <strong>and</strong> the unobserved effects causes the r<strong>and</strong>om effects estimator to be <strong>in</strong>consistent.Altogether, this po<strong>in</strong>ts to the advisability <strong>of</strong> us<strong>in</strong>g a hybrid technique that lies between bothextremes. Moreover, the potential existence <strong>of</strong> measurement errors <strong>and</strong>/or endogeneityrequires <strong>in</strong>strumental variables (IV) to obta<strong>in</strong> consistent estimates <strong>of</strong> the coefficients. As aconsequence, the Hausman & Taylor (1981) estimator is the most adequate, s<strong>in</strong>ce it has been


Returns to Education <strong>and</strong> ExperienceWith<strong>in</strong> the EU: An Instrumental Variable Approach for Panel Data 81shown to be an Efficient Generalised Instrumental Variable (EGIV). This procedure allowssimultaneous control for the correlation between regressors <strong>and</strong> unobserved <strong>in</strong>dividualeffects (as fixed effects) <strong>and</strong> to identify the estimates for the time-<strong>in</strong>variant covariates, suchas education, as a r<strong>and</strong>om effects estimator. Furthermore, it elim<strong>in</strong>ates the uncerta<strong>in</strong>tyassociated with the choice <strong>of</strong> <strong>in</strong>struments, s<strong>in</strong>ce exogenous <strong>in</strong>cluded variables, <strong>and</strong> theirmeans over time, are used as efficient <strong>in</strong>struments.Our results show that returns to education are greater for workers <strong>in</strong> paid work, with nonl<strong>in</strong>earities<strong>in</strong> the relationship between wages <strong>and</strong> educational levels (the so-called sheepsk<strong>in</strong>effect). Both f<strong>in</strong>d<strong>in</strong>gs po<strong>in</strong>t to the relevance <strong>of</strong> signall<strong>in</strong>g <strong>in</strong> the earn<strong>in</strong>gs <strong>of</strong> workers.Earn<strong>in</strong>gs experience pr<strong>of</strong>iles are, however, not very different across groups, especially whenexperience is not very great, <strong>in</strong>dicat<strong>in</strong>g absence <strong>of</strong> delays <strong>in</strong> remuneration for workers.<strong>The</strong> rest <strong>of</strong> the chapter is structured as follows. In the next section, we consider thetheoretical aspects <strong>of</strong> the returns to education <strong>and</strong> experience. Section 3 is devoted to theempirical model <strong>and</strong> to a discussion <strong>of</strong> the estimation procedure, the EGIV techniqueproposed <strong>in</strong> Hausman <strong>and</strong> Taylor (1981). Section 4 describes the data <strong>in</strong> the samplecountries. Section 5 <strong>of</strong>fers the estimates <strong>of</strong> the rates <strong>of</strong> return <strong>and</strong> exam<strong>in</strong>es the differencesacross countries to cast some light on labour-status differences. F<strong>in</strong>ally, Section 6 provides asummary <strong>of</strong> the ma<strong>in</strong> results.2. <strong>The</strong>oretical aspects <strong>of</strong> returns to school<strong>in</strong>g <strong>and</strong> experience <strong>in</strong> relation toself-employmentA new-born child enjoys an <strong>in</strong>itial endowment <strong>of</strong> human capital (a conglomerate <strong>of</strong><strong>in</strong>telligence, ability, motivation, characteristics <strong>of</strong> the social <strong>and</strong> economic environment, etc.)that can be improved upon by knowledge accumulation, both dur<strong>in</strong>g the school<strong>in</strong>g period<strong>and</strong> through on-the-job experience. Accord<strong>in</strong>g to the human capital theory (Becker, 1962,1964), there exists a positive relationship between <strong>in</strong>vestment <strong>in</strong> human capital <strong>and</strong>earn<strong>in</strong>gs, <strong>in</strong> such a way that a greater accumulation <strong>of</strong> human capital is rewarded <strong>in</strong> thelabor market with higher earn<strong>in</strong>gs.<strong>The</strong> <strong>in</strong>dividual chooses to stay <strong>in</strong> school until the expected marg<strong>in</strong>al benefit equals theexpected marg<strong>in</strong>al costs <strong>of</strong> one additional year <strong>of</strong> school<strong>in</strong>g, <strong>and</strong> differences <strong>in</strong> abilityamong <strong>in</strong>dividuals cause school<strong>in</strong>g choices to also differ. Empirically, a l<strong>in</strong>ear relationship isusually assumed between the log <strong>of</strong> the earn<strong>in</strong>gs <strong>and</strong> the set <strong>of</strong> regressors. This implies thatability <strong>in</strong>fluences only the <strong>in</strong>tercept <strong>of</strong> log-earn<strong>in</strong>gs. Follow<strong>in</strong>g this reason<strong>in</strong>g, we apply thewidely-used wage equation (M<strong>in</strong>cer, 1974) that can be expressed as:ln w t = f(A t ) + g(Edu t ) + h(Exp t ) + η’Char t + t (1)where w denotes earn<strong>in</strong>gs, A the <strong>in</strong>itial human capital, or ability, Edu is the educationvariable, Exp is the experience <strong>and</strong> Char a set <strong>of</strong> personal <strong>and</strong> labor characteristics (such asgender, age, occupation, type <strong>of</strong> contract, etc.) which can be time-constant or time-vary<strong>in</strong>g.S<strong>in</strong>ce ability is usually unobservable to the researcher, this must be <strong>in</strong>cluded <strong>in</strong> the errorterm. However, this ability may be correlated with school<strong>in</strong>g, <strong>in</strong> such a way that st<strong>and</strong>ardleast squares yield biased estimates (Griliches, 1977). This issue will be discussed further <strong>in</strong>Section 3.2.Although specification (1) has been derived on the grounds <strong>of</strong> human capital theory,compet<strong>in</strong>g perspectives may generate similar conclusions. In particular, the sort<strong>in</strong>g orsignal<strong>in</strong>g model also predicts that higher earn<strong>in</strong>gs are positively related to higher


82Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applicationseducational atta<strong>in</strong>ments. However, <strong>in</strong> this case, greater human capital does not lead tohigher productivity (<strong>and</strong> thus, higher earn<strong>in</strong>gs), but greater human capital is acquired <strong>in</strong>order to signal higher productivity (Spence, 1973; Stiglitz, 1975). In other words, firms donot reward productivity <strong>in</strong> a direct way because this is not observed a priori; rather, they<strong>in</strong>fer productivity from education, <strong>and</strong> students choose an education level to signal theirproductivity to potential employers. Similarly, firms <strong>of</strong>fer higher wages for the highlyeducated, s<strong>in</strong>ce education acts as a screen<strong>in</strong>g device, so long as education is positivelycorrelated with the unobserved productivity.As a consequence, estimat<strong>in</strong>g equation (1) does not help to discrim<strong>in</strong>ate between humancapital <strong>and</strong> the sort<strong>in</strong>g models; while it may be viewed as a good approach to assess<strong>in</strong>g theeffect <strong>of</strong> school<strong>in</strong>g on earn<strong>in</strong>gs, it is not completely satisfactory <strong>in</strong> elucidat<strong>in</strong>g which viewprevails <strong>in</strong> the process <strong>of</strong> wage determ<strong>in</strong>ation (Weiss, 1995). However, consider<strong>in</strong>g the selfemployedas a control group may serve as a device to <strong>in</strong>vestigate the question, s<strong>in</strong>cesignal<strong>in</strong>g <strong>and</strong> screen<strong>in</strong>g purposes seem to be unimportant for this group <strong>of</strong> workers (Riley,1979; Wolp<strong>in</strong>, 1977). <strong>The</strong> null hypothesis adopted by these authors is that returns toeducation will be higher <strong>in</strong> those occupations that exhibit signal<strong>in</strong>g, on the basis that it isdifficult to reconcile the idea that education for the self-employed could act as a sort<strong>in</strong>gmechanism. As a consequence, returns to school<strong>in</strong>g for those <strong>in</strong> paid employment should behigher, s<strong>in</strong>ce those <strong>in</strong>dividuals benefit from the dual effect <strong>of</strong> education: the productive <strong>and</strong>the <strong>in</strong>formative functions. By contrast, the self-employed are only remunerated for theproductive nature <strong>of</strong> education <strong>and</strong>, thus, returns are lower.However, although the theoretical implications seem quite clear-cut, the empirical evidenceis not conclusive. Focus<strong>in</strong>g on the US, some authors report that self-employed earn<strong>in</strong>gs areless responsive to human capital variables than wage-employed earn<strong>in</strong>gs (Hamilton, 2000),thereby favour<strong>in</strong>g the sort<strong>in</strong>g hypothesis., whereas others (Evans <strong>and</strong> Jovanovic, 1989;Evans <strong>and</strong> Leighton, 1989; Kawaguchi, 2003) f<strong>in</strong>d that self-employed earn<strong>in</strong>gs equationshave larger school<strong>in</strong>g coefficients than those correspond<strong>in</strong>g to the wage-employed, reject<strong>in</strong>gthe sort<strong>in</strong>g hypothesis.Dist<strong>in</strong>guish<strong>in</strong>g between self-employed <strong>and</strong> wage-earner returns may also be helpful <strong>in</strong>provid<strong>in</strong>g <strong>in</strong>sights <strong>in</strong>to the features <strong>of</strong> theoretical labour market models. Thus, study<strong>in</strong>g theexperience pr<strong>of</strong>ile <strong>in</strong> earn<strong>in</strong>gs may serve to ascerta<strong>in</strong> whether agency issues, learn<strong>in</strong>g <strong>and</strong>match<strong>in</strong>g models, or compensat<strong>in</strong>g differentials theory, for example, better fit the labourmarket. A number <strong>of</strong> studies predict that earn<strong>in</strong>gs-experience pr<strong>of</strong>iles are flatter for the selfemployed.Under the agency or risk theories (Lazear, 1981; Lazear & Moore, 1984),employers should pay less than the marg<strong>in</strong>al productivity to workers when they are young,<strong>and</strong> more when they grow older, to avoid shirk<strong>in</strong>g on the job, contrary to the case <strong>of</strong> theself-employed, given that these <strong>in</strong>dividuals have no <strong>in</strong>centive to shirk. Similarly,asymmetric <strong>in</strong>formation models (Salop & Salop, 1976) argue that, because employers are<strong>in</strong>terested <strong>in</strong> m<strong>in</strong>imiz<strong>in</strong>g the quits <strong>of</strong> more productive workers, they <strong>of</strong>fer tilted-up wagepr<strong>of</strong>iles as a screen<strong>in</strong>g device, <strong>in</strong> such a way that only workers with low probabilities <strong>of</strong>quitt<strong>in</strong>g apply for jobs. By contrast, s<strong>in</strong>ce the self-employed are not will<strong>in</strong>g to quit, they haveflatter earn<strong>in</strong>gs pr<strong>of</strong>iles than those <strong>of</strong> wage earners. In the same ve<strong>in</strong>, learn<strong>in</strong>g models claimthat, due to sector-specific abilities that are unknown for the <strong>in</strong>dividual, workers may notmatch themselves to the appropriate sector. Those who realize they have a poor match quittheir jobs, <strong>and</strong> only those with relatively good matches stay. This situation causes experiencepr<strong>of</strong>iles to <strong>in</strong>crease over time (Jovanovic, 1979, 1982). Furthermore, s<strong>in</strong>ce the self-employedhabitually <strong>in</strong>vest strongly at the start-up <strong>of</strong> their bus<strong>in</strong>esses, they are not able to move out <strong>of</strong>


Returns to Education <strong>and</strong> ExperienceWith<strong>in</strong> the EU: An Instrumental Variable Approach for Panel Data 83their poor match, <strong>and</strong> therefore their experience pr<strong>of</strong>iles are flatter (Dunn & Holt-Eak<strong>in</strong>,2000). All <strong>of</strong> these studies suggest steeper experience pr<strong>of</strong>iles for wage earners, especially atthe very end <strong>of</strong> the years <strong>of</strong> experience distribution, to ensure long seniority <strong>in</strong> the firm.Contrary results, however, are found <strong>in</strong> the <strong>in</strong>vestment model, for example, which validatesthe claim that the self-employed obta<strong>in</strong> steeper earn<strong>in</strong>gs pr<strong>of</strong>iles because physical <strong>and</strong>human capital <strong>in</strong>vestments are not shared with an employer (Hashimoto, 1981). Similarly,steeper earn<strong>in</strong>g pr<strong>of</strong>iles <strong>of</strong> the self-employed can be observed <strong>in</strong> the cases where averagereturns to experience are distorted by the existence <strong>of</strong> a few, but very successful,entrepreneurs (the so-called “superstars”), whereas the bulk <strong>of</strong> the self-employed rema<strong>in</strong>with low returns or leave for paid employment (Rosen, 1981).In summary, undisputed conclusions about the magnitude <strong>of</strong> the returns to education <strong>and</strong>experience for the self-employed <strong>and</strong> for salaried employees have not been achieved. <strong>The</strong>majority <strong>of</strong> prior analyses have focused on <strong>in</strong>vestigat<strong>in</strong>g only one country, without <strong>of</strong>fer<strong>in</strong>gany k<strong>in</strong>d <strong>of</strong> comparative study. Furthermore, only a limited number <strong>of</strong> articles have useddata for a period <strong>of</strong> more than one year. Even when they have done so, they have estimatedreturns by pool<strong>in</strong>g the data, an approach which does not allow for control for theunobserved characteristics <strong>of</strong> the <strong>in</strong>dividuals, nor for movements <strong>in</strong>to or out <strong>of</strong> selfemployment.Additionally, only the recent availability <strong>of</strong> panel data <strong>and</strong> the development <strong>of</strong>new statistical packages have permitted the application <strong>of</strong> EGIV techniques <strong>in</strong> order to ga<strong>in</strong>efficiency <strong>in</strong> estimations. <strong>The</strong> aim <strong>of</strong> this chapter is precisely to address some <strong>of</strong> these gaps<strong>in</strong> the literature by comput<strong>in</strong>g returns to education <strong>and</strong> experience for a set <strong>of</strong> EU countries,us<strong>in</strong>g <strong>in</strong>formation provided <strong>in</strong> panel data form, which are statistically efficient.3. <strong>The</strong> empirical model <strong>and</strong> estimation procedureThis section focuses on the empirical specification <strong>of</strong> the earn<strong>in</strong>gs equation <strong>and</strong> themethodology used for its estimation. <strong>The</strong> first sub-section is devoted to determ<strong>in</strong><strong>in</strong>g themost appropriate empirical model for our study, while the second describes the logicsupport<strong>in</strong>g the use <strong>of</strong> the Hausman-Taylor procedure <strong>in</strong> the estimation.3.1 Empirical specificationAs discussed <strong>in</strong> Section 2, estimates <strong>of</strong> the returns to education <strong>and</strong> experience for the selfemployed<strong>and</strong> wage earners are usually obta<strong>in</strong>ed from M<strong>in</strong>cer-type wage regressions.Dat<strong>in</strong>g from the mid 20 th century, a body <strong>of</strong> empirical work has <strong>in</strong>vestigated these returnsacross countries on the basis <strong>of</strong> such a specification (Psacharapoulos, 1973, 1981, 1985, 1994;Trostel et al., 2002). Cross-sectional <strong>in</strong>formation has normally been used, with the IVapproach, progressively substitut<strong>in</strong>g for the traditional OLS estimation to account forendogeneity <strong>and</strong> ability biases, as well as measurement errors. This has resulted <strong>in</strong> estimates<strong>of</strong> the rates <strong>of</strong> return well above those obta<strong>in</strong>ed from OLS (Card, 1999, 2001).Our estimated model is an extended version <strong>of</strong> the M<strong>in</strong>cerian-basel<strong>in</strong>e equation (1), <strong>in</strong> whichearn<strong>in</strong>gs reward<strong>in</strong>g more education can be seen as the comb<strong>in</strong>ed effect <strong>of</strong> human capitalaccumulation <strong>and</strong> the effect <strong>of</strong> be<strong>in</strong>g identified as a graduate rather than as a dropout. Ittakes the follow<strong>in</strong>g form:ln w it = βEdu i + 1 Exp it + 2 Exp 2 it/100 + X' it + Z' i γ + u it , (2)where i <strong>and</strong> t st<strong>and</strong> for the N <strong>in</strong>dividuals <strong>and</strong> the T time periods, respectively. As <strong>in</strong>dicatedbefore, w denotes earn<strong>in</strong>gs; Edu is the education variable (that is considered time-<strong>in</strong>variant);


84Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> ApplicationsExp is the experience; X is a set <strong>of</strong> time-vary<strong>in</strong>g regressors, <strong>and</strong> Z is a set <strong>of</strong> time-<strong>in</strong>variantregressors. <strong>The</strong> β coefficient expresses the rate <strong>of</strong> return to education; 1 <strong>and</strong> 2 represent theearn<strong>in</strong>gs-experience pr<strong>of</strong>ile, <strong>and</strong> <strong>and</strong> γ are the set <strong>of</strong> parameters accompany<strong>in</strong>g therema<strong>in</strong><strong>in</strong>g regressors.Rather than us<strong>in</strong>g the education measure normally employed <strong>in</strong> the literature, years <strong>of</strong>school<strong>in</strong>g, we consider the educational atta<strong>in</strong>ment <strong>of</strong> each worker, provid<strong>in</strong>g two clearadvantages. First, it does not impose the annual marg<strong>in</strong>al effect <strong>of</strong> school<strong>in</strong>g as be<strong>in</strong>g thesame <strong>in</strong> each year <strong>of</strong> education, <strong>and</strong> second, the level <strong>of</strong> education is a more appropriatemeasure, s<strong>in</strong>ce multiple education streams characterize European countries, <strong>and</strong> salarypr<strong>of</strong>iles used to be largely l<strong>in</strong>ked to the education category atta<strong>in</strong>ed. In other words, theycapture the possibility that credentials matter more than years <strong>of</strong> school<strong>in</strong>g per se <strong>in</strong> thewage determ<strong>in</strong>ation. This hypothesis is commonly known as the “sheepsk<strong>in</strong> effect” <strong>and</strong>attempts to expla<strong>in</strong> the discont<strong>in</strong>uous changes <strong>in</strong> earn<strong>in</strong>gs associated with completion <strong>of</strong>elementary school, high school or college (Belman & Heywood, 1991; Hungeford & Solon,1987; Jaeger & Page, 1996).Educational atta<strong>in</strong>ment, which is considered time-<strong>in</strong>variant <strong>in</strong> our sample, represents thelast completed level <strong>of</strong> school<strong>in</strong>g, classified as primary, secondary, <strong>and</strong> high. Primary<strong>in</strong>cludes elementary <strong>and</strong> below elementary school, secondary <strong>in</strong>cludes vocational <strong>and</strong>middle school, <strong>and</strong> tertiary or high <strong>in</strong>cludes university studies (<strong>in</strong> either short or longcycles). Consequently, the fragment “β Edu i ” <strong>in</strong> equation (2) would be represented by “β 1EduS i + β 2 EduH i ”. <strong>The</strong> category <strong>of</strong> reference is EduP i , omitted <strong>in</strong> the estimation.ln w it = β 1 EduS i + β 2 EduH i + 1 Exp it + 2 Exp 2 it/100 + X' it + Z' i γ + u it , (3)<strong>The</strong> dependent variable is the natural log <strong>of</strong> net earn<strong>in</strong>gs, where these are def<strong>in</strong>ed as grossearn<strong>in</strong>gs less tax, expressed <strong>in</strong> per hour real terms. <strong>The</strong> earn<strong>in</strong>gs-experience pr<strong>of</strong>iles areanalyzed by consider<strong>in</strong>g the number <strong>of</strong> years that an <strong>in</strong>dividual has been work<strong>in</strong>g, <strong>and</strong> itssquared value divided by 100 to take care <strong>of</strong> the decreas<strong>in</strong>g returns. Specifically, experienceis measured as the difference between the current age <strong>and</strong> the age <strong>of</strong> <strong>in</strong>itiation at work,thereby express<strong>in</strong>g potential experience. <strong>The</strong> rema<strong>in</strong><strong>in</strong>g <strong>in</strong>dependent variables, represented<strong>in</strong> equation (3) by X <strong>and</strong> Z, conta<strong>in</strong> dummies for gender, marital status, tra<strong>in</strong><strong>in</strong>g, occupation,sector, seniority, <strong>and</strong> a set <strong>of</strong> time fixed effects, as described <strong>in</strong> Section 4.3.2 Estimat<strong>in</strong>g the earn<strong>in</strong>gs equation: the Hausman-Taylor procedure<strong>The</strong> general model <strong>in</strong> (3) assumes that the error term u it consists <strong>of</strong> the sum <strong>of</strong> twocomponents, i.e. u it = α i + v it , where α i represents the r<strong>and</strong>om <strong>in</strong>dividual-specific effect thatcharacterizes each worker <strong>and</strong> is constant through time, <strong>and</strong> v it is a r<strong>and</strong>om disturbancevary<strong>in</strong>g over time <strong>and</strong> <strong>in</strong>dividuals. This latter stochastic term is assumed to be uncorrelatedwith all <strong>in</strong>cluded variables. Similarly, it is also assumed that the r<strong>and</strong>om disturbance is asequence <strong>of</strong> i.i.d. r<strong>and</strong>om variables with mean zero <strong>and</strong> variance 2 v; that v it <strong>and</strong> i aremutually <strong>in</strong>dependent, <strong>and</strong> that i is i.i.d. over the panels with mean zero <strong>and</strong> variance 2 .Thus, the variance-covariance matrix <strong>of</strong> the system has the r<strong>and</strong>om effects structure that canbe represented as E(UU’) = 2 (i T i T ’ I N ) + 2 v (I T I N ), where i T is a Tx1 vector conta<strong>in</strong><strong>in</strong>g1s, I N (I T ) is the identity matrix <strong>of</strong> rank N (T), <strong>and</strong> U is an NTx1 vector <strong>of</strong> disturbances. Thus,r<strong>and</strong>om-effects or Generalised Leasts Squares (GLS) produce consistent estimators.However, the presence <strong>of</strong> measurement errors <strong>and</strong> unobserved variables, such as ability,motivation, etc., that may be correlated with school<strong>in</strong>g, bias GLS estimates. Specifically, it


Returns to Education <strong>and</strong> ExperienceWith<strong>in</strong> the EU: An Instrumental Variable Approach for Panel Data 85has been shown that measurement errors bias downwards the GLS estimates (Angrist <strong>and</strong>Krueger, 1999) although recent evidence (Card, 2001) only attributes a 10% gap, at most, tothis source <strong>of</strong> bias. By contrast, s<strong>in</strong>ce school<strong>in</strong>g <strong>and</strong> any unobserved ability may bepositively correlated, omitt<strong>in</strong>g measures <strong>of</strong> ability results <strong>in</strong> the school<strong>in</strong>g coefficient be<strong>in</strong>gbiased upwards (Griliches, 1977). Consequently, some effort must be made to alleviate suchan ability bias as much as possible. When a direct <strong>in</strong>dication <strong>of</strong> ability, such as IQ score tests,or <strong>in</strong>formation from tw<strong>in</strong>s or sibl<strong>in</strong>gs, is not available (see Ashenfelter & Krueger, 1994, <strong>and</strong>Miller et al., 1995), the most appropriate exercise is to select an <strong>in</strong>strumental variablesestimator, through which school<strong>in</strong>g is <strong>in</strong>strumented with variables that are correlated withit, but not with errors. A broad range <strong>of</strong> <strong>in</strong>struments have been proposed <strong>in</strong> the literature.Typical examples are those known as natural experiments (see Rosenzweig <strong>and</strong> Wolp<strong>in</strong>,2000, for a summary) which <strong>in</strong>clude: i) school reforms <strong>and</strong> features <strong>of</strong> the school system(Harmon <strong>and</strong> Walker, 1995); ii) the proximity to College <strong>of</strong> the place <strong>of</strong> residence (Card,1995); iii) other supply-side <strong>in</strong>struments captur<strong>in</strong>g features <strong>of</strong> the education system (seeCard, 2001 for a survey <strong>of</strong> the literature); <strong>and</strong> iv) the season <strong>of</strong> birth <strong>of</strong> the <strong>in</strong>dividual(Angrist <strong>and</strong> Krueger, 1991).When us<strong>in</strong>g IV <strong>in</strong> cross-sections, a common f<strong>in</strong>d<strong>in</strong>g is that estimates are 20% higher, or evenmore, than OLS estimates. This is a rather unexpected result, s<strong>in</strong>ce OLS is already believedto provide upward-biased estimates aris<strong>in</strong>g from the ability bias. Some reasons have beenproposed to expla<strong>in</strong> such a result. Apart from the positive publication bias (Ashenfelter etal., 1999), IV estimates may be biased upwards further than OLS due to the existence <strong>of</strong>unobserved differences between the characteristics <strong>of</strong> the treatment <strong>and</strong> comparison groupsimplicit <strong>in</strong> the IV scheme (Bound et al., 1995). Specifically, when treatment effects are used,s<strong>in</strong>ce returns to education are heterogeneous across <strong>in</strong>dividuals, the IV estimates tend torecover the returns to education <strong>of</strong> the population group most affected by the <strong>in</strong>tervention,so that IV estimates are then a better approximation for the returns to education <strong>of</strong> theaffected group, rather than for the whole population (Card, 1999, 2001). Similarly, IVestimates will tend to be biased towards the returns to school<strong>in</strong>g atta<strong>in</strong>ments that are mostcommon <strong>in</strong> the sample data (see Belzil <strong>and</strong> Hansen, 2002).Both the available data structure <strong>and</strong> the existence <strong>of</strong> problems associated with the choice <strong>of</strong><strong>in</strong>struments have <strong>in</strong>fluenced the procedure applied <strong>in</strong> this study. On the one h<strong>and</strong>, theECHP is <strong>in</strong> panel data form, but does not provide <strong>in</strong>formation on IQ tests, <strong>and</strong> the presence<strong>of</strong> tw<strong>in</strong>s is not especially accounted for. On the other h<strong>and</strong>, although the number <strong>of</strong>alternative <strong>in</strong>struments rout<strong>in</strong>ely considered <strong>in</strong> the literature is sufficiently wide, theirapplication to our data is quite complex. This has led us to consider an alternative procedurefor estimation, <strong>in</strong> which the availability <strong>of</strong> panel data is taken <strong>in</strong>to account, namely the IVtypemodel proposed by Hausman <strong>and</strong> Taylor (1981). Our selection <strong>of</strong> this procedure ismotivated by several considerations. As is well known, the availability <strong>of</strong> panel data allowsus to control for <strong>in</strong>dividual unobserved heterogeneity (possibly correlated with other<strong>in</strong>cluded variables), s<strong>in</strong>ce this factor may be elim<strong>in</strong>ated by mean or time-differenc<strong>in</strong>g, i.e. byapply<strong>in</strong>g a fixed effects-type estimator (Polachek & Kim, 1994). Although this with<strong>in</strong>estimator is probably not fully-efficient, it produces consistent estimates. However, whenoperat<strong>in</strong>g <strong>in</strong> this way, coefficients <strong>of</strong> the time-constant variables (e.g. the level <strong>of</strong> education)cannot be estimated, s<strong>in</strong>ce they disappear when mean or time-differences are constructed.For its part, a pure r<strong>and</strong>om effects estimator, the GLS, produces biased <strong>and</strong> <strong>in</strong>consistentestimates, assum<strong>in</strong>g as it does that there is no correlation between any <strong>of</strong> the regressors <strong>and</strong>


86Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applicationsthe <strong>in</strong>dividual effects. In our case, the GLS estimator is not valid because education <strong>and</strong>experience may be correlated with <strong>in</strong>dividual effects.One way to obta<strong>in</strong> consistent estimates <strong>of</strong> the returns to education <strong>and</strong> experience would beto f<strong>in</strong>d <strong>in</strong>struments for these variables which are potentially correlated with the <strong>in</strong>dividualeffects. <strong>The</strong> choice <strong>of</strong> the appropriate <strong>in</strong>struments is, however, not an easy task, s<strong>in</strong>ce the use<strong>of</strong> <strong>in</strong>struments that are weakly correlated with endogenous variables may producedownward-biased estimates, even with large samples (see Bound et al, 1995; Chamberla<strong>in</strong> &Imbens, 2004; Staiger & Stock, 1997), generat<strong>in</strong>g uncerta<strong>in</strong>ty <strong>in</strong> the selection <strong>of</strong> <strong>in</strong>struments.Consequently, what we require is a procedure that controls for the endogeneity <strong>of</strong> education(<strong>and</strong> possibly other variables), but which is still able to recover the coefficient <strong>of</strong> time<strong>in</strong>variantregressors. Hausman & Taylor (1981) propose a model where some <strong>of</strong> theregressors may be correlated with <strong>in</strong>dividual effects, as opposed to the r<strong>and</strong>om effectsmodel, where no regressor can be correlated with the <strong>in</strong>dividual effect, <strong>and</strong> to the fixedeffects model, where all the regressors may be correlated with <strong>in</strong>dividual effects. If, <strong>in</strong>addition, this procedure does not require <strong>in</strong>struments excluded <strong>in</strong> the regression but the<strong>in</strong>struments used are precisely those <strong>in</strong>cluded <strong>in</strong> the wage regression, the Hausman-Taylorestimator is, potentially, the best choice.This Hausman-Taylor estimator is an <strong>in</strong>strumental variables estimator that uses both thebetween <strong>and</strong> with<strong>in</strong> variations <strong>of</strong> the strictly exogenous variables as <strong>in</strong>struments. Morespecifically, the <strong>in</strong>dividual means <strong>of</strong> the strictly exogenous regressors are used as<strong>in</strong>struments for the time <strong>in</strong>variant regressors correlated with <strong>in</strong>dividual effects. Thisprocedure is implemented <strong>in</strong> the follow<strong>in</strong>g steps. First, equation (3) is estimated by pooledTwo Stages Least Squares (2SLS), where the set <strong>of</strong> variables mentioned above act as<strong>in</strong>struments. Second, the pooled 2SLS residuals are used to obta<strong>in</strong> estimates <strong>of</strong> 2 <strong>and</strong> 2 v,which can then be used to construct the weights for a Feasible Generalized Least Squaresestimator. Third, these weights are used to transform (by quasi-time demean<strong>in</strong>g) all thedependent, explanatory, <strong>and</strong> <strong>in</strong>strumental variables. F<strong>in</strong>ally, the transformed regression isaga<strong>in</strong> estimated by pooled 2SLS, where the <strong>in</strong>dividual means, over time, <strong>of</strong> the time-vary<strong>in</strong>gregressors, <strong>and</strong> the exogenous time-<strong>in</strong>variant regressors, are the <strong>in</strong>struments. Under the fullset <strong>of</strong> assumptions mentioned <strong>in</strong> the previous sub-section, this Hausman <strong>and</strong> Taylorestimator becomes an Efficient Generalized Instrumental Variables (EGIV) <strong>and</strong> co<strong>in</strong>cideswith the efficient GMM estimator.Formally, the Hausman-Taylor model can be represented <strong>in</strong> its most general form asfollows:ln w it = i + X' it + Z' i γ + v it , (4)where i = 1, …, N <strong>and</strong> t = 1,…, T. <strong>The</strong> Z i are <strong>in</strong>dividual time-<strong>in</strong>variant regressors, whereasthe X it are time-vary<strong>in</strong>g. i is assumed to be i.i.d.(0, 2 ) <strong>and</strong> v it i.i.d.(0, 2 v), both<strong>in</strong>dependent <strong>of</strong> each other. <strong>The</strong> matrices X <strong>and</strong> Z can be split <strong>in</strong>to two sets <strong>of</strong> variablesX=[X 1 , X 2 ] <strong>and</strong> Z=[Z 1 , Z 2 ], such that X 1 is NT x k 1 , X 2 is NT x k 2 , Z 1 is NT x g 1 , <strong>and</strong> Z 2 is NT xg 2 . <strong>The</strong> X 1 <strong>and</strong> Z 1 are assumed exogenous <strong>and</strong> not correlated with i <strong>and</strong> v it , while X 2 <strong>and</strong> Z 2are endogenous due to their correlation with i but not with v it . Hausman & Taylor (1981)suggest an <strong>in</strong>strumental variables estimator which pre-multiplies expression (4) by -1/2 ,where is the variance- covariance term <strong>of</strong> the error component i + v it , <strong>and</strong> thenperform<strong>in</strong>g 2SLS us<strong>in</strong>g [Q, X 1 , Z 1 ] as <strong>in</strong>struments. Q is the with<strong>in</strong> transformation matrixwith X* = QX hav<strong>in</strong>g a typical element X * it = X it -X i <strong>and</strong>X i is the <strong>in</strong>dividual mean. This is


Returns to Education <strong>and</strong> ExperienceWith<strong>in</strong> the EU: An Instrumental Variable Approach for Panel Data 87equivalent to runn<strong>in</strong>g 2SLS with [X*, X 1 , Z 1 ] as the set <strong>of</strong> <strong>in</strong>struments. If the model isidentified, <strong>in</strong> the sense that there are at least as many time-vary<strong>in</strong>g exogenous regressors X 1as there are <strong>in</strong>dividual time-<strong>in</strong>variant endogenous regressors Z 2 , i.e. k 1 g 2 , this Hausman-Taylor estimator is more efficient than fixed effects. If the model is under-identified, i.e. k 1


88Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applicationsmore than 8,000 <strong>in</strong> Germany. For the self-employed, the figures are considerably lower,vary<strong>in</strong>g between less than 1,000 <strong>in</strong> Germany to almost 2,500 <strong>in</strong> Italy. Sample proportions arenot very different from population rates (see Table 1). Bear<strong>in</strong>g <strong>in</strong> m<strong>in</strong>d that self-employedearn<strong>in</strong>gs are commonly believed to be under-reported (Hamilton, 2000), wage earnersappear to earn a little more than the self-employed <strong>in</strong> Italy, whereas the opposite occurs <strong>in</strong>Germany <strong>and</strong> <strong>in</strong> the UK. Note that dispersion <strong>in</strong> earn<strong>in</strong>gs is higher for the self-employed,reflect<strong>in</strong>g a greater heterogeneity <strong>in</strong> these types <strong>of</strong> activities, from low-ability jobs (retailers<strong>and</strong> basic services) to those <strong>of</strong> pr<strong>of</strong>essionals, such as doctors or lawyers. People liv<strong>in</strong>g <strong>in</strong>Germany <strong>and</strong> <strong>in</strong> the UK obta<strong>in</strong> higher earn<strong>in</strong>gs than those resid<strong>in</strong>g <strong>in</strong> Italy.<strong>The</strong> years <strong>of</strong> experience are clearly higher <strong>in</strong> the self-employed sector than <strong>in</strong> that <strong>of</strong> wageearners. <strong>The</strong> majority <strong>of</strong> <strong>in</strong>dividuals <strong>in</strong> Italy present low educational levels, the percentagebe<strong>in</strong>g somewhat higher among the self-employed. By contrast, <strong>in</strong> Germany, workers <strong>in</strong>general are highly educated, with more than 40% <strong>of</strong> the self-employed hav<strong>in</strong>g atta<strong>in</strong>ed atertiary degree. <strong>The</strong> case <strong>of</strong> the UK is especially appeal<strong>in</strong>g s<strong>in</strong>ce workers atta<strong>in</strong><strong>in</strong>g asecondary level are clearly fewer than those <strong>of</strong> primary or higher education, <strong>in</strong>dicat<strong>in</strong>g somek<strong>in</strong>d <strong>of</strong> a bi-modal distribution. Roughly speak<strong>in</strong>g, where self-employment rates are higher,the self-employed themselves are less educated, as aga<strong>in</strong>st countries with low selfemploymentrates, which exhibit a higher proportion <strong>of</strong> workers, either wage earners or theself-employed, who have obta<strong>in</strong>ed at least a secondary level <strong>of</strong> education.GermanyItalyUnitedK<strong>in</strong>gdomSelfemployedWageearnerSelfemployedWageearnerSelfemployedWageearnerEarn<strong>in</strong>gsper hour9.06(8.26)8.48(4.30)6.21(5.31)6.73(3.55)8.71(9.73)7.88(5.59)Exp.22.94(10.98)20.48(11.16)23.69(13.34)18.03(11.07)25.33(13.03)20.02(12.86)Primaryeduc.Secondaryeduc.Highereduc.Obs.peryear12.31 46.19 41.50 84019.48 57.88 22.64 806656.82 31.95 11.23 249444.13 44.63 11.24 786546.48 13.74 39.78 105345.99 13.70 40.31 6433Table 2. Sample averages (ECHP 1994-2000). Note: St<strong>and</strong>ard errors between parentheses.Earn<strong>in</strong>gs are expressed <strong>in</strong> terms <strong>of</strong> the PPP. Observations per year is the average, s<strong>in</strong>cefigures vary from year to year.5. <strong>Estimation</strong> resultsThis section presents the empirical evidence which is then assessed <strong>in</strong> the light <strong>of</strong> the aspectsmentioned <strong>in</strong> Section 2, with the aim <strong>of</strong> provid<strong>in</strong>g some <strong>in</strong>sights <strong>in</strong>to the function<strong>in</strong>g <strong>of</strong> theEuropean labour markets. <strong>The</strong> results from EGIV Hausman-Taylor estimations are shown <strong>in</strong>Table 3, along with the tests for choos<strong>in</strong>g the appropriate <strong>in</strong>struments (Baltagi et al., 2003).In column H1, a st<strong>and</strong>ard Hausman test rejects the r<strong>and</strong>om effects hypotheses <strong>in</strong> favour <strong>of</strong>


Returns to Education <strong>and</strong> ExperienceWith<strong>in</strong> the EU: An Instrumental Variable Approach for Panel Data 89the fixed effect estimator. A second Hausman test contrast<strong>in</strong>g the Hausman-Taylor aga<strong>in</strong>stthe fixed effects model (column H2), is useful <strong>in</strong> order to test the strict exogeneity <strong>of</strong> theregressors used as <strong>in</strong>struments <strong>in</strong> the Hausman-Taylor estimation. Once this secondHausman test has identified which regressors are strictly exogenous, they are then used as<strong>in</strong>struments <strong>in</strong> the Hausman-Taylor estimation.Compar<strong>in</strong>g the coefficients <strong>of</strong> Table 3 with those from the GLS estimation (not shown, butavailable from the authors upon request), we can note that the Hausman-Taylor estimationprovides coefficients <strong>of</strong> education <strong>and</strong> experience that, <strong>in</strong> general, are consistently muchhigher. This is <strong>in</strong> accordance with the typical f<strong>in</strong>d<strong>in</strong>g reported <strong>in</strong> the literature when us<strong>in</strong>g<strong>in</strong>strumental variables <strong>of</strong> upward bias <strong>in</strong> IV-type, compared to OLS-type estimations.Regard<strong>in</strong>g the returns to education, wages <strong>in</strong>crease with educational atta<strong>in</strong>ment, withreturns higher among wage earners <strong>in</strong> Germany <strong>and</strong> Italy <strong>and</strong> quite similar <strong>in</strong> the UK, <strong>and</strong>the coefficients for the self-employed with secondary education level <strong>in</strong> Germany <strong>and</strong> theUK are non-significant. <strong>The</strong> percentage changes across educational categories, computed asthe difference <strong>in</strong> the percentage change <strong>in</strong> wage for group i relative to the group i-1, e βi - e βi-1 ,where β i is the coefficient for the dummy variable for group I, show that returns <strong>in</strong>crease aswe move up the qualification ladder, especially from secondary to higher education, whichsupports a convex configuration <strong>of</strong> earn<strong>in</strong>gs on the returns to education, thus confirm<strong>in</strong>g theimportance <strong>of</strong> the sheepsk<strong>in</strong> effect. Both results, higher returns to education for paidworkers, <strong>and</strong> <strong>in</strong>creas<strong>in</strong>g non-l<strong>in</strong>earities <strong>in</strong> the relationship between wages <strong>and</strong> educationalatta<strong>in</strong>ment, <strong>in</strong>dicate some degree <strong>of</strong> a sort<strong>in</strong>g or signall<strong>in</strong>g role played by education.CountryGermanyItalyUnitedK<strong>in</strong>gdomLabourstatusSelfemployedWageearnersSelfemployedWageearnersSelfemployedWageearnersExp. Exp. 2 /1000.053**(3.72)0.065**(22.24)0.037**(6.30)0.047**(27.52)0.053**(5.16)0.063**(27.27)-0.068**(-2.83)-0.084**(-22.21)-0.053**(-4.66)-0.089**(-23.60)-0.055**(-3.41)-0.106**(-27.28)Second.education0.654(0.89)0.848**(8.83)0.339**(2.78)0.551**(15.09)0.629(0.74)0.524**(3.41)Highereducation1.243*(2.45)1.291**(17.31)0.631**(6.35)0.847**(19.07)0.714**(3.54)0.706**(15.14)H1234.96(0.0000)1117.89(0.0000)138.47(0.0000)2103.26(0.0000)275.90(0.0000)2064.11(0.0000)H28.44(0.9986)10.51(0.9921)34.66(0.0946)49.63(0.0752)5.92(0.9999)4.58(1.0000)Table 3 Estimated Coefficients <strong>of</strong> M<strong>in</strong>cerian Earn<strong>in</strong>gs Function by Hausman-Taylor. Notes:t-ratios between parentheses (p-values <strong>in</strong> H1 <strong>and</strong> H2). Both panels are unbalanced, s<strong>in</strong>ce theemployment status may vary across <strong>in</strong>dividuals over time. Controls used. Gender: 1 formale <strong>and</strong> 0 for female. Marital status: married, s<strong>in</strong>gle, divorced, widow or separated.Tra<strong>in</strong><strong>in</strong>g: if the worker has realized some course <strong>of</strong> occupational tra<strong>in</strong><strong>in</strong>g. Eight dummiesthat <strong>in</strong>dicate occupation. A dummy <strong>in</strong>dicat<strong>in</strong>g whether the <strong>in</strong>dividual works <strong>in</strong> the privateor the public sector. Dummies that <strong>in</strong>dicate seniority: less than two years, between 2 <strong>and</strong> 10years, <strong>and</strong> more than 10 years. Dummies that <strong>in</strong>dicate the year. * Significant at the 5% level.** Significant at the 1% level. H1 tests the r<strong>and</strong>om effects estimator aga<strong>in</strong>st the fixed effects.H2 tests the Hausman-Taylor estimator aga<strong>in</strong>st the fixed effects.


90Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> ApplicationsAcross countries, experience <strong>in</strong>creases human capital accumulation dur<strong>in</strong>g the life cycle. Atfirst sight, returns to experience are greater for wage earners, even though they depreciate ata faster rate than <strong>in</strong> the case <strong>of</strong> the self-employed. In order to extract more robustconclusions, a series <strong>of</strong> <strong>in</strong>dicators are used. First, the maximum return, i.e. the po<strong>in</strong>t whereexperience ceases to add positively to earn<strong>in</strong>gs, which is def<strong>in</strong>ed by lnw/Exp fromearn<strong>in</strong>gs equation (3), that is to say, the number <strong>of</strong> years that equals 1 + 2 Exp/50 to 0provided 2


Returns to Education <strong>and</strong> ExperienceWith<strong>in</strong> the EU: An Instrumental Variable Approach for Panel Data 91Fig. 1. Earn<strong>in</strong>gs experience pr<strong>of</strong>iles for the three sample countriesgeneral, found to be higher for wage earners, which can be <strong>in</strong>terpreted as an <strong>in</strong>dication <strong>of</strong>the relevance <strong>of</strong> the signall<strong>in</strong>g role <strong>of</strong> education <strong>in</strong> determ<strong>in</strong><strong>in</strong>g earn<strong>in</strong>gs. This latter resultwas expected, bear<strong>in</strong>g <strong>in</strong> m<strong>in</strong>d the prevalent wage rates <strong>in</strong> the EU countries, where earn<strong>in</strong>gsare usually l<strong>in</strong>ked to the education level atta<strong>in</strong>ed by the worker. Second, accord<strong>in</strong>g to theevidence shown by the earn<strong>in</strong>g-experience pr<strong>of</strong>iles, which tend to be steeper <strong>in</strong> the case <strong>of</strong>the self-employed, traits <strong>of</strong> competitiveness can be discerned, with little or no evidence <strong>of</strong>imperfections.


92Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications6. Conclusions<strong>The</strong> aim <strong>of</strong> this Chapter has been to extend the exist<strong>in</strong>g research on the returns to humancapital accumulation that differentiates between the self-employed <strong>and</strong> wage earners. Thishas been carried out by provid<strong>in</strong>g evidence <strong>in</strong> a cross-country framework us<strong>in</strong>g ahomogenous database, which mitigates the problems associated with the existence <strong>of</strong>different data sources across countries, by us<strong>in</strong>g a panel data approach that is useful <strong>in</strong>deal<strong>in</strong>g with endogeneity <strong>and</strong> selectivity biases, as well as unobserved heterogeneity, <strong>and</strong>by apply<strong>in</strong>g an efficient estimation method that allows for the correlation between<strong>in</strong>dividual effects <strong>and</strong> time-<strong>in</strong>variant regressors, <strong>and</strong> that avoids the <strong>in</strong>security associatedwith the choice <strong>of</strong> the appropriate <strong>in</strong>struments.Information from the ECHP for the period 1994-2000 has been used, allow<strong>in</strong>g us to apply anEfficient Generalised Instrumental Variable estimator that provides consistent estimates <strong>of</strong>the rates <strong>of</strong> return to education <strong>and</strong> experience. Education has been represented bydummies <strong>of</strong> qualification levels (primary, secondary <strong>and</strong> higher), <strong>and</strong> experience has beenmeasured as the difference between the current age <strong>and</strong> the age <strong>of</strong> <strong>in</strong>itiation at work. <strong>The</strong>results have been presented <strong>in</strong> a reduced form, with the aim be<strong>in</strong>g to provide bothcomparisons across countries about the earn<strong>in</strong>gs differentials between the two employmentstatuses analyzed, <strong>and</strong> evidence as to whether such differences are consistent with thepredictions <strong>of</strong>fered by a variety <strong>of</strong> theoretical models.<strong>The</strong> self-employed have been used as a control group to help <strong>in</strong> assess<strong>in</strong>g the true impact <strong>of</strong>credentials achieved <strong>in</strong> the process <strong>of</strong> wage determ<strong>in</strong>ation, as well as <strong>in</strong> determ<strong>in</strong><strong>in</strong>g whichtype <strong>of</strong> theoretical structure underlies labour market behavior. We have operated under thepremise that, on the basis that signall<strong>in</strong>g is <strong>of</strong> much less importance for the self-employed,compar<strong>in</strong>g across both types <strong>of</strong> employment statuses should show that, for the sort<strong>in</strong>ghypothesis to be accepted, returns to education for wage earners are significantly higherthan those for the self-employed, as well as possibly <strong>in</strong>creas<strong>in</strong>g <strong>in</strong> a non-l<strong>in</strong>ear way.Similarly, most labour market models based on imperfect <strong>in</strong>formation predict steeperexperience-earn<strong>in</strong>gs pr<strong>of</strong>iles for wage earners, whereas competitive traits <strong>in</strong> the labormarket would imply similar or flatter pr<strong>of</strong>iles for this category <strong>of</strong> worker.<strong>The</strong> evidence that emerges for the sample countries tends to support the view that signall<strong>in</strong>gtheory is <strong>in</strong>deed relevant <strong>in</strong> determ<strong>in</strong><strong>in</strong>g <strong>in</strong>dividual earn<strong>in</strong>gs, <strong>in</strong> that, first, returns toeducation are lower where signall<strong>in</strong>g is expected to play a less important role, i.e. <strong>in</strong> the case<strong>of</strong> the self-employed, <strong>and</strong>, second, certa<strong>in</strong> non-l<strong>in</strong>earities appear. Furthermore, earn<strong>in</strong>gsexperiencepr<strong>of</strong>iles are found to be steeper for the self-employed <strong>in</strong> the long-run, <strong>in</strong>dicat<strong>in</strong>ga certa<strong>in</strong> significance <strong>of</strong> competitiveness <strong>in</strong> the labour markets.Some aspects <strong>of</strong> the <strong>in</strong>vestigation have been omitted or require further attention. We areconscious that selectivity issues should be carefully dealt with, when the development <strong>of</strong> areliable <strong>in</strong>strument makes this possible (Semyk<strong>in</strong>a & Wooldridge, 2010). Furthermore,obta<strong>in</strong><strong>in</strong>g structural estimates for the returns to education <strong>and</strong> experience would probablyrequire dynamic programm<strong>in</strong>g models <strong>of</strong> occupational choice (Belzil & Hansen, 2002).F<strong>in</strong>ally, the availability <strong>of</strong> richer panel data sets is <strong>of</strong> particular importance to control for themovements <strong>in</strong>to <strong>and</strong> out <strong>of</strong> self-employment. <strong>The</strong>se topics are all matters for future research,<strong>and</strong> will undoubtedly be helpful <strong>in</strong> carry<strong>in</strong>g out a more <strong>in</strong>-depth <strong>in</strong>vestigation <strong>in</strong>to thebehaviour <strong>of</strong> the labour market <strong>and</strong> wage determ<strong>in</strong>ation <strong>in</strong> the EU countries, <strong>in</strong> such a waythat we can more fully assess their degrees <strong>of</strong> competitiveness.


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Us<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong> forNeighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway6A. Khalik SalmanMid Sweden University, Social science / Economics DepartmentSweden1. IntroductionThis chapter estimates the <strong>in</strong>ternational dem<strong>and</strong> for tourism <strong>in</strong> two neighbour<strong>in</strong>g regions:the objective number 6 (SW:6) <strong>in</strong> Sweden <strong>and</strong> North Norway <strong>in</strong>cluded – Tröndelag (NWT)<strong>in</strong> North Norway, from five different countries: Denmark, the United K<strong>in</strong>gdom,Switzerl<strong>and</strong>, Japan, <strong>and</strong> the United States. For each visit<strong>in</strong>g country, <strong>and</strong> for Sweden <strong>and</strong>Norway, we specify separate equations by <strong>in</strong>clud<strong>in</strong>g the relevant <strong>in</strong>formation. we thenestimate these ten equations us<strong>in</strong>g Zellner’s Iterative Seem<strong>in</strong>gly Unrelated Regressions(ISUR). <strong>The</strong> benefit <strong>of</strong> this model is that the ISUR estimators utilize the <strong>in</strong>formation with<strong>in</strong><strong>and</strong> the relation between the equations present <strong>in</strong> the error correlation <strong>of</strong> the crossregressions (or equations) <strong>and</strong> hence is more efficient than s<strong>in</strong>gle equation estimationmethods such as ord<strong>in</strong>ary least squares. Monthly time series data from 1993:01 to 2006:12are used. <strong>The</strong> results show that the consumer price <strong>in</strong>dex, some lagged dependent variables,<strong>and</strong> several monthly dummies (represent<strong>in</strong>g seasonal effects) have significant impacts onthe number <strong>of</strong> visitors to the SW:6 region <strong>in</strong> Sweden <strong>and</strong> NWT region <strong>in</strong> Norway. We als<strong>of</strong><strong>in</strong>d that, <strong>in</strong> at least some cases, relative prices <strong>and</strong> exchange rates have significant effects on<strong>in</strong>ternational tourism dem<strong>and</strong>.Tourism has important impacts on the economies <strong>of</strong> both develop<strong>in</strong>g <strong>and</strong> <strong>in</strong>dustrializedcountries, result<strong>in</strong>g <strong>in</strong> job creation, additional <strong>in</strong>come for the private <strong>and</strong> public sectors,foreign currency receipts, higher <strong>in</strong>vestment <strong>and</strong> growth. Indeed, tourism has acted as acatalyst to economic restructur<strong>in</strong>g <strong>in</strong> many recipient countries, assist<strong>in</strong>g a shift away fromprimary sector activities, towards greater reliance on services <strong>and</strong> manufactur<strong>in</strong>g. Given thescale <strong>of</strong> tourism’s contribution to the macroeconomic dimension over time, knowledgeconcern<strong>in</strong>g the nature <strong>of</strong> the dem<strong>and</strong> upon which it is based is <strong>of</strong> both theoretical <strong>and</strong>practical relevance. It is well known that tourism dem<strong>and</strong> is responsive to such variables as<strong>in</strong>come, relative prices <strong>and</strong> exchange rates. What is not known is how the responsiveness <strong>of</strong>dem<strong>and</strong> to changes <strong>in</strong> these variables alters dur<strong>in</strong>g a country’s economic transition <strong>and</strong><strong>in</strong>tegration <strong>in</strong>to the wider world <strong>in</strong>itial or subsequent years? Does the sensitivity <strong>of</strong> tourismdem<strong>and</strong> to changes <strong>in</strong> its own prices, or those <strong>of</strong> its competitors, change between differentperiods? Further questions concern the degrees <strong>of</strong> complementarity or substitutabilitybetween tourism dest<strong>in</strong>ations <strong>and</strong> the extent to which these change dur<strong>in</strong>g periods <strong>of</strong>economic transition. Complementarity occurs if holidays <strong>in</strong> different dest<strong>in</strong>ations arepurchased as a package. Alternatively, there may be an <strong>in</strong>tense degree <strong>of</strong> competitionbetween dest<strong>in</strong>ations. Relationships <strong>of</strong> complementarity or substitutability may change over


98Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applicationstime as lower <strong>in</strong>come dest<strong>in</strong>ations emerge from relative poverty to achieve a higher level <strong>of</strong>development. Little <strong>in</strong>formation is available about this issue. It is not known, for example,whether lower <strong>in</strong>come dest<strong>in</strong>ations tend to become more or less competitive over time,either relative to other develop<strong>in</strong>g countries or relative to more <strong>in</strong>dustrialized nations.Different models have been used to estimate tourism dem<strong>and</strong> <strong>and</strong> some types <strong>of</strong> model aremore appropriate for exam<strong>in</strong><strong>in</strong>g the above questions than others. <strong>The</strong> vast majority <strong>of</strong>studies <strong>of</strong> tourism dem<strong>and</strong> have relied on s<strong>in</strong>gle equation models <strong>of</strong> dem<strong>and</strong>, estimatedwith<strong>in</strong> a static context (for example, Uysal <strong>and</strong> Crompton, 1984; Gunadhi <strong>and</strong> Boey,1986).<strong>The</strong>se models are not derived from consumer dem<strong>and</strong> theory <strong>and</strong> fail to quantify thechanges <strong>in</strong> dem<strong>and</strong> behaviour that occur over time. Innovations <strong>in</strong> the methodology weresubsequently <strong>in</strong>troduced <strong>in</strong> the form <strong>of</strong> s<strong>in</strong>gle equation models <strong>of</strong> dem<strong>and</strong> estimated us<strong>in</strong>gan error correction methodology were subsequently <strong>in</strong>troduced <strong>in</strong> s<strong>in</strong>gle equation model <strong>of</strong>dem<strong>and</strong> estimated us<strong>in</strong>g an error correction methodology (Syriopoulos, 1995). Kulendran(1996) used a general to specific, error correction model to estimate the Australia dem<strong>and</strong>for tourism <strong>in</strong> the form <strong>of</strong> visits per capita to outbound dest<strong>in</strong>ations <strong>and</strong> demonstrated thatthe model has good forecast<strong>in</strong>g ability. This modell<strong>in</strong>g approach has the advantage <strong>of</strong>explicit treatment <strong>of</strong> the time dimension <strong>of</strong> tourism dem<strong>and</strong> behaviour <strong>and</strong> allows forimproved econometric estimation <strong>of</strong> the specified equations.A More recently approach to tourism dem<strong>and</strong> estimation <strong>in</strong>volves a system -wide approachby us<strong>in</strong>g the ISUR Model (Salman et al. 2010). This system <strong>of</strong> study is particularly useful fortest<strong>in</strong>g the properties <strong>of</strong> homogeneity <strong>and</strong> symmetry which are basic to consumer dem<strong>and</strong>theory. Hence, it provides a stronger theoretical basic for estimat<strong>in</strong>g the cross- priceelasticities <strong>of</strong> dem<strong>and</strong> than the s<strong>in</strong>gle equation approach.This chapter was used system wise approach by the ISUR Model to exam<strong>in</strong>e tourismdem<strong>and</strong> by the UK, Switzerl<strong>and</strong>, Denmark, Japan <strong>and</strong> <strong>The</strong> USA <strong>in</strong> the neighbor<strong>in</strong>gdest<strong>in</strong>ation number 6 (SW:6) <strong>and</strong> (NWT) <strong>in</strong> Norway. <strong>The</strong> UK, Switzerl<strong>and</strong>, Denmark, Japan<strong>and</strong> <strong>The</strong> USA are major orig<strong>in</strong> countries for tourism <strong>in</strong> the dest<strong>in</strong>ations under consideration.SW:6 <strong>in</strong> Sweden <strong>and</strong> NWT <strong>in</strong> Norway are key dest<strong>in</strong>ations, account<strong>in</strong>g for over one-third<strong>of</strong> all receipts from tourism <strong>in</strong> the European Union <strong>in</strong> 2005. <strong>The</strong> absolute value <strong>of</strong> theirreceipts from tourism is very high, at over $ 200 million <strong>in</strong> 2005. <strong>The</strong> choice <strong>of</strong> the countriesas dest<strong>in</strong>ations for analysis is also appropriate ow<strong>in</strong>g to their position as geographicneighbours. Complementarity or substitutability <strong>in</strong> tourism dem<strong>and</strong>, as <strong>in</strong>dicated by thesigns <strong>of</strong> the relative-price elasticities <strong>of</strong> dem<strong>and</strong>, is <strong>of</strong> particular relevance <strong>in</strong> this context.This chapter pays attention to this issue, which has not previously been exam<strong>in</strong>ed for thecase <strong>of</strong> neighbour<strong>in</strong>g countries us<strong>in</strong>g the ISUR approach. Sweden <strong>and</strong> Norway are<strong>in</strong>terest<strong>in</strong>g cases for consideration ow<strong>in</strong>g to their position as economies <strong>in</strong> transition dur<strong>in</strong>gthe period under consideration. By the early 1990s, the start years <strong>of</strong> the period under study,they had adopted new development policies, high dependence on <strong>in</strong>dustry, mov<strong>in</strong>gtowards <strong>in</strong>creased globalization, economic <strong>in</strong>tegration, <strong>and</strong> foreign competition. Swedenhad jo<strong>in</strong>ed the ranks <strong>of</strong> the more developed European economies <strong>in</strong> the period under study.Hence, an <strong>in</strong>novative feature <strong>of</strong> this chapter is its exam<strong>in</strong>ation <strong>of</strong> the evolution <strong>of</strong> tourismdem<strong>and</strong> dur<strong>in</strong>g these countries’ transition to a new technological system <strong>and</strong> globalizationstatus. It also permits exam<strong>in</strong>ation <strong>of</strong> the extent to which the behaviour <strong>of</strong> dem<strong>and</strong> becomemore or less similar over time with respect to changes <strong>in</strong> prices <strong>and</strong> exchange rates. Thus,this study provides useful <strong>in</strong>formation, at the cross-country level, about change <strong>in</strong> a majoractivity with<strong>in</strong> each <strong>of</strong> the economies.


Us<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong> for Neighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway 99<strong>The</strong> aim <strong>of</strong> this chapter is to estimate <strong>in</strong>ternational tourism dem<strong>and</strong> to the two neighbour<strong>in</strong>gregions: objective number 6 (SW:6) <strong>in</strong> Sweden <strong>and</strong> North Norway <strong>in</strong>cluded – TröndelagFig. 1. Swedish <strong>and</strong> Norwegian Maps; <strong>The</strong> Objective 6 region (SW: 6) <strong>in</strong> Sweden is thelightly shadowed area at the top <strong>and</strong> top-left <strong>of</strong> the map <strong>of</strong> Sweden. <strong>The</strong> North –Norway<strong>in</strong>cluded <strong>and</strong> Tröndelag region <strong>in</strong> Norway (NWT) is the lightly shadowed part on the topright <strong>of</strong> the map <strong>of</strong> Norway.(NWT) by five countries: namely, Denmark, the United K<strong>in</strong>gdom (UK), Switzerl<strong>and</strong>, Japan,<strong>and</strong> the United States (US). S<strong>in</strong>ce these two regions are geographically very close to eachothers <strong>and</strong> highly competitive (although they are located <strong>in</strong> two different countries) webelieve that they can be considered as one larger region with respect to the very similarnature <strong>and</strong> tourism facilities they supply. For this reason we study the dem<strong>and</strong> for these tworegions simultaneously together by specify<strong>in</strong>g a separate equation for these regions from therespective visit<strong>in</strong>g countries. We then merge the ten equations <strong>in</strong> one system <strong>of</strong> regressionequations model that will be estimated by Zellner’s ISUR model.Previous Sc<strong>and</strong><strong>in</strong>avian studies did not study <strong>and</strong> compare the tourism dem<strong>and</strong> for Sweden<strong>and</strong> Norway <strong>in</strong> one overall regression model. Further, previous studies <strong>of</strong> Norwegian tourismdem<strong>and</strong> have not considered the relative price <strong>and</strong> substitution effect or complementarity, thereal <strong>and</strong> nom<strong>in</strong>al exchange rate, <strong>and</strong> personal <strong>in</strong>come. With this method <strong>of</strong> estimation, I can


100Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applicationscome closer to study<strong>in</strong>g the impact <strong>of</strong> the <strong>in</strong>fluences <strong>of</strong> cultural values, climate naturalattraction on the tourism dem<strong>and</strong>. This has earlier been difficult to quantify.<strong>The</strong> purpose <strong>of</strong> this chapter is to use Iterative Seem<strong>in</strong>gly Unrelated Regressions (ISUR) toestimate the relationship between monthly tourist arrivals to Sweden <strong>and</strong> Norway fromDenmark, the UK, Switzerl<strong>and</strong>, Japan, <strong>and</strong> the US <strong>and</strong> the factors that <strong>in</strong>fluence arrivals. Tothis end, we use a dem<strong>and</strong> function approach to tourism flow modell<strong>in</strong>g. A large modelconsist<strong>in</strong>g <strong>of</strong> ten equations for Sweden <strong>and</strong> Norway (five for each country) was estimated bythe ISUR technique.<strong>The</strong> idea <strong>of</strong> merg<strong>in</strong>g the equations from both countries <strong>in</strong>to one overall model, <strong>in</strong> fact, isnecessary to measure the tourism dem<strong>and</strong> to neighbour<strong>in</strong>g regions that are close <strong>in</strong> theirgeographical characters, see Figure 1. In other words, tourists can receive the same utilityfrom either region. An important question is “Are there differences between the hedonicregressions for the two neighbourhoods, or not?” If there are no differences, then the datafrom the two neighbourhoods can be pooled <strong>in</strong>to one sample without parameter restrictions<strong>and</strong> with no allowance made for differ<strong>in</strong>g slope or <strong>in</strong>tercept. Moreover, the estimation hasbeen done by us<strong>in</strong>g the ISUR regression.<strong>The</strong>re is no previous application <strong>of</strong> this technique to tourism dem<strong>and</strong> modell<strong>in</strong>g for thesetwo regions. With the ISUR technique, we estimate the entire system <strong>of</strong> equations by tak<strong>in</strong>g<strong>in</strong>to account any possible correlations between the residuals from the different equations.Moreover, the ISUR technique provides parameter estimates that converge to uniquemaximum likelihood parameter estimates.<strong>The</strong> rema<strong>in</strong>der <strong>of</strong> the chapter is organized as follows. Section 2 discusses tourism dem<strong>and</strong>for Nordic countries <strong>and</strong> the data used. Section 3 presents the estimation <strong>and</strong> test<strong>in</strong>gmethodology. Section 4 provides the results. This chapter has a brief summary <strong>and</strong>conclusion <strong>in</strong> Section 5.2. Economic factors <strong>and</strong> the model specification<strong>The</strong> objective <strong>of</strong> this section is to analyze how the follow<strong>in</strong>g macroeconomic <strong>and</strong>microeconomic variables <strong>and</strong> seasonal (monthly) conditions <strong>in</strong>fluence the dem<strong>and</strong> fortourism for the (SW:6) <strong>and</strong> (NWT):1. <strong>The</strong> Swedish Consumer Price Index (CPI) represents the <strong>in</strong>flation rate <strong>and</strong> cost <strong>of</strong> liv<strong>in</strong>g<strong>in</strong> Sweden <strong>and</strong> is <strong>in</strong> natural logarithms. <strong>The</strong> CPI has several advantages for thispurpose: it is familiar to the public <strong>and</strong> is the most widely used measure <strong>of</strong> <strong>in</strong>flation <strong>in</strong>Sweden (Andersson <strong>and</strong> Berg, 1995). We adjust the CPI for any changes <strong>in</strong> <strong>in</strong>direct taxes<strong>and</strong> subsidies.2. I use dummy variables for January to November to proxy for seasonal effects(December is the base category).3. <strong>The</strong> exchange rate (EX) between the Swedish/Norwegian currencies <strong>and</strong> the visitors’country <strong>of</strong> orig<strong>in</strong> currency are <strong>in</strong>cluded <strong>in</strong> natural logarithms.4. <strong>The</strong> relative price (Pr) reflects opportunity cost. This represents the cost <strong>of</strong> liv<strong>in</strong>g <strong>in</strong>relative terms for Norway <strong>and</strong> Sweden <strong>and</strong> a substitute price for an orig<strong>in</strong> countrytourist. <strong>The</strong>se are also <strong>in</strong> natural logarithms.<strong>The</strong> SW:6 is a major tourist dest<strong>in</strong>ation worldwide, with the yearly dem<strong>and</strong> for tourism <strong>in</strong>this part <strong>of</strong> Sweden <strong>and</strong> NWT consistently follow<strong>in</strong>g an upward trend. However,<strong>in</strong>terruption to these trends has taken place on a number <strong>of</strong> occasions due to economic


Us<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong> for Neighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway 101conditions <strong>and</strong>/or <strong>in</strong>ternational events. For example, September 11 <strong>and</strong> the first Gulf Warhad a detrimental effect on tourism dem<strong>and</strong> <strong>in</strong> both Sweden <strong>and</strong> Norway.A common model used <strong>in</strong> tourism dem<strong>and</strong> studies is a s<strong>in</strong>gle equation with dem<strong>and</strong>expla<strong>in</strong>ed by the tourist’s <strong>in</strong>come <strong>in</strong> their country <strong>of</strong> orig<strong>in</strong>, the cost <strong>of</strong> tourism <strong>in</strong> theirchosen <strong>and</strong> alternative dest<strong>in</strong>ations, <strong>and</strong> a substitute price (Witt <strong>and</strong> Mart<strong>in</strong>, 1987). To startwith, the dem<strong>and</strong> for tourism can be expressed <strong>in</strong> a variety <strong>of</strong> ways. <strong>The</strong> most appropriatevariable to represent dem<strong>and</strong> expla<strong>in</strong>ed by economic factors is consumer expenditure orreceipts (Grouch, 1992). Other measures <strong>of</strong> dem<strong>and</strong> are the nights spent by the tourist ortheir length <strong>of</strong> stay. However, due to the lack <strong>of</strong> data on monthly GDP, personal <strong>in</strong>come(GDP/Population) is not <strong>in</strong>cluded <strong>in</strong> this analysis.<strong>The</strong> tourism price <strong>in</strong>dex (the price <strong>of</strong> the holiday) is also an important determ<strong>in</strong>ant <strong>of</strong> thedecision a potential tourist makes. We can divide this <strong>in</strong>to two components: (i) the cost <strong>of</strong>liv<strong>in</strong>g for the tourist at the dest<strong>in</strong>ation, <strong>and</strong> (ii) the cost <strong>of</strong> travel or transport to thedest<strong>in</strong>ation. I divide the cost <strong>of</strong> liv<strong>in</strong>g <strong>in</strong>to two components: (i) the CPI <strong>in</strong> relative price formassum<strong>in</strong>g that tourists have the option <strong>of</strong> spend<strong>in</strong>g their vacation <strong>in</strong> either SW:6 or NWT,<strong>and</strong> (ii) tourist consumer expenditure, real consumer expenditure, real <strong>in</strong>come, <strong>and</strong> percapita <strong>in</strong>come (Salman, 2003). In this chapter, CPI represents the cost <strong>of</strong> liv<strong>in</strong>g. However, wemeasure transport costs by the weighted mean prices accord<strong>in</strong>g to the transport mode usedby tourists to reach the dest<strong>in</strong>ation. Changes <strong>in</strong> travel costs, particularly airfares, can have amajor impact on tourism dem<strong>and</strong>. Unfortunately, data on economy class airfares betweenStockholm <strong>and</strong> the capital cities <strong>of</strong> the countries <strong>of</strong> orig<strong>in</strong> were not consistently available, soI could not use these <strong>in</strong> construction <strong>of</strong> the variables. Moreover, one should also take <strong>in</strong>toaccount the small proportion <strong>of</strong> tourists who arrive <strong>in</strong> Sweden us<strong>in</strong>g charter flights dest<strong>in</strong>edfor regional airports closer to the ma<strong>in</strong> tourist resorts, as the airfares for these may differconsiderably from those to the capital city’s airport. <strong>The</strong>refore, <strong>in</strong> the absence <strong>of</strong> a suitableproxy, I exclude travel costs from our dem<strong>and</strong> system (Lathiras <strong>and</strong> Siriopoulos, 1998).In previous Sc<strong>and</strong><strong>in</strong>avian tourism dem<strong>and</strong> studies, the cost <strong>of</strong> liv<strong>in</strong>g component wasdef<strong>in</strong>ed <strong>in</strong> relative price form, assum<strong>in</strong>g that the tourists have the option <strong>of</strong> spend<strong>in</strong>g theirvacation <strong>in</strong> Sweden or at home. <strong>The</strong> probability <strong>of</strong> travel to the dest<strong>in</strong>ation decl<strong>in</strong>es if thedest<strong>in</strong>ation price level <strong>in</strong>creased faster than that <strong>of</strong> the orig<strong>in</strong> price due to a substitutioneffect, <strong>and</strong> also if the if the reserves occurred <strong>and</strong> hence the tourist’s real <strong>in</strong>come decreasedto the substitution effect .In this study, the cost <strong>of</strong> liv<strong>in</strong>g (relative price) component is def<strong>in</strong>ed as the Norwegian pricerelative to the price <strong>of</strong> a holiday <strong>in</strong> Sweden. <strong>The</strong> underly<strong>in</strong>g assumption is that for thetourists, SW: -6 <strong>in</strong> Sweden is a substitute long-haul holiday dest<strong>in</strong>ation for NWT <strong>in</strong> Norway.In recent years, SW:6 <strong>in</strong> Sweden <strong>and</strong> NWT <strong>in</strong> Norway have been compet<strong>in</strong>g with each otherto attractive more tourists. <strong>The</strong> tourists from these five countries have the option <strong>of</strong>spend<strong>in</strong>g vacations on SW:6 <strong>in</strong> Sweden or NWT <strong>in</strong> Norway, both hav<strong>in</strong>g similar mounta<strong>in</strong>s<strong>and</strong> ski<strong>in</strong>g facilities <strong>in</strong> w<strong>in</strong>ter <strong>and</strong> similar climate. Furthermore, for visitors from these fivecountries mentioned above, the travel distances to SW:- 6 <strong>in</strong> Sweden <strong>and</strong> NWT <strong>in</strong> Norwayare almost the same. <strong>The</strong>refore, for potential visitors, SW:6 is consider a substitute long-haulholiday dest<strong>in</strong>ation for the NWT <strong>and</strong> the cost <strong>of</strong> liv<strong>in</strong>g variable for the tourism dem<strong>and</strong>model is def<strong>in</strong>ed as the cost <strong>of</strong> liv<strong>in</strong>g <strong>in</strong> SW:6 relative to that for NWT <strong>in</strong> Norway .Follow<strong>in</strong>g previous research, we can specify the price <strong>of</strong> tourism at the dest<strong>in</strong>ation <strong>in</strong> avariety <strong>of</strong> ways. For <strong>in</strong>stance, we can represent prices <strong>in</strong> either absolute or relative terms. Inthis chapter, we employ the relative price as an opportunity cost. We def<strong>in</strong>e this as the ratio<strong>of</strong> the CPI <strong>of</strong> the host country (CPI SW ) to the country <strong>of</strong> orig<strong>in</strong> adjusted by the relative


102Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applicationsexchange rate (R it ) to obta<strong>in</strong> a proxy for the real cost <strong>of</strong> liv<strong>in</strong>g (Salman, 2004). <strong>The</strong>refore, thereal cost <strong>of</strong> tourism <strong>in</strong> Sweden <strong>and</strong> Norway are the relative CPIs given by:CPI itEX ijtRp (1)jtCPI jtwhere i is the host country (Sweden or Norway), j is the visit<strong>in</strong>g (or foreign) country, <strong>and</strong> t istime. Rp it is the relative CPI for country i <strong>in</strong> time t, CPI it is the CPI for Sweden or Norway,CPI jt is the CPI for the foreign country, <strong>and</strong> EX ijt is the exchange rate between the Swedishkrona/Norwegian krone <strong>and</strong> the foreign currency.In addition to the price variable, the exchange rate is a relevant factor <strong>in</strong> determ<strong>in</strong><strong>in</strong>gtourism dem<strong>and</strong>. <strong>The</strong> rationale beh<strong>in</strong>d <strong>in</strong>corporation <strong>of</strong> the exchange rate as a separateexplanatory variable is that tourists may be more aware <strong>of</strong> the relative exchange rate thanthe specific cost <strong>of</strong> tourism at the dest<strong>in</strong>ation. A question that arises is whether the exchangerate should be <strong>in</strong>cluded <strong>in</strong> our model system as an explanatory variable together with theprice variable. In an attempt to f<strong>in</strong>d a variable to represent a tourist’s cost <strong>of</strong> liv<strong>in</strong>g, Salman,Shukur, <strong>and</strong> Bergmann-W<strong>in</strong>berg (2007) concluded that the CPI (either alone or with theexchange rate) is a reasonable proxy <strong>of</strong> the cost <strong>of</strong> tourism. And also the exchange rate <strong>and</strong>price are used <strong>in</strong> this study as proxy variables for the structural transformation <strong>in</strong> these twosmall open economies <strong>and</strong> the expansion <strong>in</strong> <strong>in</strong>ternational competitions faced by them. Wedef<strong>in</strong>e the exchange rate variable as the foreign exchange rate <strong>of</strong> the Swedish Krona orNorwegian Krona to the currency <strong>of</strong> the orig<strong>in</strong> country. This variable represents therelationship between tourism dem<strong>and</strong> <strong>and</strong> the <strong>in</strong>ternational money market <strong>and</strong><strong>in</strong>ternational economic events (<strong>in</strong>clud<strong>in</strong>g recessions <strong>and</strong> f<strong>in</strong>ancial crises) as well.As microeconomic theory suggests, the price <strong>of</strong> other goods <strong>in</strong>fluences the dem<strong>and</strong> for aparticular good. In the case <strong>of</strong> tourism, the identification <strong>and</strong> separation <strong>of</strong> substituteproducts is very difficult to achieve on an a priori basis. In our case, tourists consider NWTregion (<strong>in</strong> the North <strong>of</strong> Norway) an alternative dest<strong>in</strong>ation to the SW:6 region (<strong>in</strong> the north<strong>of</strong> Sweden). <strong>The</strong>se dest<strong>in</strong>ations are among the most popular dest<strong>in</strong>ations <strong>in</strong> Sc<strong>and</strong><strong>in</strong>avia, atleast <strong>in</strong> terms <strong>of</strong> arrivals, for tourists from the orig<strong>in</strong> countries under:Relative price <strong>of</strong> tourism for DenmarkRelative price <strong>of</strong> tourism for the UKRelative price <strong>of</strong> tourism for Switzerl<strong>and</strong>CPISweK/ EXSEK/DKK (2)CPI / EXNorNOK/DKKCPISwe/ EXSEK/GBP (3)CPI / EXNorNOK/GBPCPISwe/ EXSEK/CHF (4)CPI / EXNorNOK/CHF


Us<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong> for Neighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway 103Relative price <strong>of</strong> tourism for JapanRelative price <strong>of</strong> tourism for the USCPI/ EXSwe SEK/JPY (5)CPINor/ EXNOK/JPYCPI/ EXSwe SEK/USD (6)CPINor/ EXNOK/USDWhere:CPI Swe : CPI <strong>in</strong> Sweden (1998 = 100).CPINor: CPI <strong>in</strong> Norway (1998 = 100).EX SEK/DKK : An <strong>in</strong>dex <strong>of</strong> the Swedish krona per unit <strong>of</strong> Danish krona (1998 = 100).EX SEK/GBP : An <strong>in</strong>dex <strong>of</strong> the Swedish krona per unit <strong>of</strong> British pound (1998 = 100).EX SEK/CHF : An <strong>in</strong>dex <strong>of</strong> the Swedish krona per unit <strong>of</strong> Swiss franc (1998 = 100).EX SEK/JPY : An <strong>in</strong>dex <strong>of</strong> the Swedish krona per unit <strong>of</strong> Japanese yen (1998 = 100).EX SEK/USD : An <strong>in</strong>dex <strong>of</strong> the Swedish krona per unit <strong>of</strong> US dollar (1998 = 100).A lagged dependent variable may also be <strong>in</strong>cluded to account for habit persistence <strong>and</strong>supply constra<strong>in</strong>ts. As for the signs <strong>of</strong> the explanatory variables, we expect a negative signfor the relative price variable <strong>and</strong> a positive sign for the exchange rate variable. In thisstudy, monthly dummies represent seasonal effects on the number <strong>of</strong> arrivals from theorig<strong>in</strong> countries. All variables are <strong>in</strong> natural logarithms, <strong>and</strong> the data are <strong>in</strong> <strong>in</strong>dex form (1998= 100). All economic data employed <strong>in</strong> this study are from Statistics Sweden (StatistiskaCentralbyrån) <strong>and</strong> Statistics Norway (Statistisk SENTRALBYRÅ). <strong>Estimation</strong> is with theSTATA Ver. 10 <strong>and</strong> EViews Ver. 5.1 statistical program packages. We exam<strong>in</strong>e monthly timeseries data from 1993:01 to 2006:12.3. Methodology3.1 Statistical assumptions <strong>and</strong> the problem <strong>of</strong> misspecificationIn the common stochastic specification <strong>of</strong> econometric models, the error terms are assumedto be normally distributed with mean zero, constant variance <strong>and</strong> serially uncorrelated.<strong>The</strong>se assumptions must be tested <strong>and</strong> verified before one can have any confidence <strong>in</strong> theestimation results or conduct any specification tests, <strong>in</strong>clud<strong>in</strong>g st<strong>and</strong>ard t-tests <strong>of</strong> parametersignificance or tests <strong>of</strong> theoretical restrictions. Because misspecification test<strong>in</strong>g is a vast area<strong>of</strong> statistical/econometric methodology, there will only be a brief description <strong>of</strong> the methodsused <strong>in</strong> this study (<strong>in</strong> the Appendix) with additional details <strong>in</strong> the cited references.<strong>The</strong> methodology used <strong>in</strong> this chapter for misspecification test<strong>in</strong>g follows Godfrey (1988)<strong>and</strong> Shukur (2002). To test for autocorrelation, we apply the F-version <strong>of</strong> the Breusch (1978)<strong>and</strong> Godfrey (1978) test. We use White (1980) test (<strong>in</strong>clud<strong>in</strong>g cross products <strong>of</strong> theexplanatory variables) to test for heteroscedasticity <strong>and</strong> Ramsey’s (1969) RESET test to testfor functional misspecification (Ramsey, 1969). We also apply the Engle (1980) LagrangeMultiplier (LM) test for the possible presence <strong>of</strong> Autoregressive ConditionalHeteroscedasticity (ARCH) <strong>in</strong> the residuals. F<strong>in</strong>ally, we apply the Jarque–Bera (1987) LMtest <strong>of</strong> non-normality to the residuals <strong>in</strong> model (4).When build<strong>in</strong>g an econometric model, the assumption <strong>of</strong> parameter consistency is widelyused because <strong>of</strong> the result<strong>in</strong>g simplicity <strong>in</strong> estimation <strong>and</strong> ease <strong>of</strong> <strong>in</strong>terpretation. However,


104Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications<strong>in</strong> situations where a structural change may have occurred <strong>in</strong> the generation <strong>of</strong> theobservations, this assumption is obviously <strong>in</strong>appropriate. Particularly <strong>in</strong> the field <strong>of</strong>econometrics where data are not generated under controlled conditions, the problem <strong>of</strong>ascerta<strong>in</strong><strong>in</strong>g whether the underly<strong>in</strong>g parameter structure is constant is <strong>of</strong> paramount<strong>in</strong>terest. However, to test for the stability <strong>of</strong> the parameters <strong>in</strong> the models, <strong>and</strong> <strong>in</strong> theabsence <strong>of</strong> any prior <strong>in</strong>formation regard<strong>in</strong>g possible structural changes, we conduct acumulative sum (CUSUM) test follow<strong>in</strong>g Brown et al. (1975). <strong>The</strong> CUSUM test is <strong>in</strong> the form<strong>of</strong> a graph <strong>and</strong> is based on the cumulative sum <strong>of</strong> the recursive residuals. Movement <strong>in</strong>these recursive residuals outside the critical l<strong>in</strong>es is suggestive <strong>of</strong> coefficient <strong>in</strong>stability.3.2 <strong>The</strong> systemic specificationIn this chapter, we aim to estimate the number <strong>of</strong> visitors to Sweden <strong>and</strong> Norway from fivecountries (Denmark, the UK, Switzerl<strong>and</strong>, Japan, <strong>and</strong> the US). For each visit<strong>in</strong>g country <strong>and</strong>for both Sweden <strong>and</strong> Norway, we specify a separate equation with the relevant <strong>in</strong>formation<strong>in</strong>cluded <strong>in</strong> each equation. For this purpose, we follow a simple strategy on how to select anappropriate model by successively exam<strong>in</strong><strong>in</strong>g the adequacy <strong>of</strong> a properly chosen sequence<strong>of</strong> models for each country separately us<strong>in</strong>g diagnostic tests with known good properties.<strong>The</strong> methodology used for misspecification test<strong>in</strong>g <strong>in</strong> this chapter follows Godfrey (1988)<strong>and</strong> Shukur (2002). We apply their l<strong>in</strong>e <strong>of</strong> reason<strong>in</strong>g to the problem <strong>of</strong> autocorrelation, <strong>and</strong>then extend it to other forms <strong>of</strong> misspecification. If we subject a model to severalspecification tests, one or more <strong>of</strong> the test statistics may be so large (or the p-values so small)that the model is clearly unsatisfactory. At that po<strong>in</strong>t, one has either to modify the model orsearch for an entirely new model.Our aim is to f<strong>in</strong>d a well-behaved model that satisfies the underly<strong>in</strong>g statisticalassumptions, which at the same time agrees with aspects <strong>of</strong> economic theory. Given theseequations, we estimate the whole system (consist<strong>in</strong>g <strong>of</strong> ten equations) us<strong>in</strong>g Zellner’s ISUR.<strong>The</strong> ISUR technique provides parameter estimates that converge to unique maximumlikelihood parameter estimates. Note that conventional seem<strong>in</strong>gly unrelated regressions(SUR) does not have this property if the numbers <strong>of</strong> variables differ between the equations,even though it is one <strong>of</strong> the most successful <strong>and</strong> efficient methods for estimat<strong>in</strong>g SUR. <strong>The</strong>result<strong>in</strong>g model has stimulated countless theoretical <strong>and</strong> empirical results <strong>in</strong> econometrics<strong>and</strong> other areas (see Zellner, 1962; Srivastava <strong>and</strong> Giles, 1987; Chib <strong>and</strong> Greenberg, 1995).<strong>The</strong> benefit <strong>of</strong> this model for us is that the ISUR estimators utilize the <strong>in</strong>formation present <strong>in</strong>the cross regression (or equations) error correlation <strong>and</strong> hence it is more efficient than otherestimation methods such as ord<strong>in</strong>ary least squares (OLS).Consider a general system <strong>of</strong> m stochastic equations given by:Y X B e i 1, 2, M(7)i i i iwhere Y i is a ( T 1) vector <strong>of</strong> dependent variables, e i is a ( T 1) vector <strong>of</strong> r<strong>and</strong>om errorswith Ee ( i ) 0, X i is a ( T n i ) matrix <strong>of</strong> observations on n i exogenous <strong>and</strong> lagged dependentvariables <strong>in</strong>clud<strong>in</strong>g a constant term, B i is a ( ni 1) dimensional vector <strong>of</strong> coefficients to beestimated, M is the number <strong>of</strong> equations <strong>in</strong> the system, T is the number <strong>of</strong> observations perequation, <strong>and</strong> n i is the number <strong>of</strong> rows <strong>in</strong> the vector B i . <strong>The</strong> m system <strong>of</strong> m equations canbe written separately as:Y X e1 1 1 1


Us<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong> for Neighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway 105Y X e2 2 2 2Y X em m m m<strong>and</strong> then comb<strong>in</strong>ed <strong>in</strong>to a larger model written as:Y1 X1 0 0 0 1 e1 Y2 0 X2 0 0 2 e2 ... 0 0 ... 0 ... ... Y m 0 0 0 X m m e mThis model can be rewritten compactly as:(8)YX Be(9)where Y <strong>and</strong> e are <strong>of</strong> dimension (TM 1), X is <strong>of</strong> dimension (TM n), n =dimension (K 1).At this stage, I make the follow<strong>in</strong>g assumptions:a. X i is fixed with rank n i .M nii1, <strong>and</strong> B is <strong>of</strong>b. P lim1 ('XX i i )T Q ii is nons<strong>in</strong>gular with f<strong>in</strong>ite <strong>and</strong> fixed elements, i.e. <strong>in</strong>vertible.c. addition, I assume that Plimd.1 ('XX i j ) Q ij is also nons<strong>in</strong>gular with f<strong>in</strong>ite <strong>and</strong> fixedTelements.,Eee ( i i) ijIT, where ij designates the covariance between the i th <strong>and</strong> j th equations foreach observation <strong>in</strong> the sample.<strong>The</strong> above expression can be written as: 11 12 1MEe () 0<strong>and</strong> ,21 22 2MEee ( ) IT, where is an M M positiveM1 M2 MMdef<strong>in</strong>ite symmetric matrix <strong>and</strong> is the Kronecker product. Thus, the errors at eachequation are assumed homoscedastic <strong>and</strong> not autocorrelated, but there is contemporaneouscorrelation between correspond<strong>in</strong>g errors <strong>in</strong> different equations.<strong>The</strong> OLS estimator <strong>of</strong> B <strong>in</strong> (9) is:with the variance 1ˆOLS XX XY Var( ˆ ) X X X X( X X)OLS 1 1 <strong>The</strong> SUR Generalized Least Squares (GLS) estimator <strong>of</strong> B is given by:


106Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications<strong>and</strong> the variance is given by: 1ˆ 1 1GLS ( T ) ( T )X I X X I Y ˆ ( 1) 1GLS TV X I XHowever, the system <strong>of</strong> the five equations for Sweden <strong>and</strong> Norway are as follows:Y it= i + S i + XitB i+ Y it-q iq + e ,it i 1, 2, 5 q 1, 2, 12(10)where Y it is a T 1 vector <strong>of</strong> observations on the dependent variable, e it is a T 1 vector <strong>of</strong>r<strong>and</strong>om errors with E(e t ) = 0 , <strong>and</strong> S i are monthly dummy variables that take valuesbetween 1 <strong>and</strong> 11 (the twelfth month is the base). X it is a T nimatrix <strong>of</strong> observations on n <strong>in</strong>onstochastic explanatory variables, <strong>and</strong> B i is an ni 1 dimensional vector <strong>of</strong> unknownlocation parameters. T is the number <strong>of</strong> observations per equation, <strong>and</strong> n i is the number <strong>of</strong>rows <strong>in</strong> the vector B i . iq is a parameter vector associated with the lagged dependentvariable for the respective equation.<strong>The</strong> dependent variables Y i are the natural logarithms <strong>of</strong> the number <strong>of</strong> monthly visitorsfrom Denmark, the UK, Switzerl<strong>and</strong>, Japan, <strong>and</strong> the US to either Sweden or Norway. <strong>The</strong>matrix X i is the natural logarithm <strong>of</strong> three vectors that conta<strong>in</strong>s monthly <strong>in</strong>formation aboutthe CPI <strong>in</strong> Sweden (or Norway), the exchange rate (Ex) <strong>in</strong> Sweden (or Norway), <strong>and</strong> relativeprice (Rp) for Sweden (or Norway) with respect to each <strong>of</strong> the abovementioned countries.Another objective <strong>of</strong> this study is to test for the existence <strong>of</strong> any contemporaneouscorrelation between the equations. If such correlation exists <strong>and</strong> is statistically significant,then least squares applied separately to each equation are not efficient <strong>and</strong> there is need toemploy another estimation method that is more efficient.<strong>The</strong> SUR estimators utilize the <strong>in</strong>formation present <strong>in</strong> the cross regression (or equations)error correlation. In this chapter, we estimated the model <strong>in</strong> Equation (10) by us<strong>in</strong>g the OLSmethod for each equation separately to achieve the best specification <strong>of</strong> each equation. Wethen estimate the whole system us<strong>in</strong>g ISUR, see Tables 2 <strong>and</strong> 3. <strong>The</strong> ISUR techniqueprovides parameter estimates that converge to unique maximum likelihood parameterestimates <strong>and</strong> take <strong>in</strong>to account any possible contemporaneous correlation between theequations.To test whether the estimated correlation between these equations is statistically significant,we apply Breusch <strong>and</strong> Pagan’s (1980) LM statistic. If we denote the covariances between thedifferent equations as 12 , 13 … 45 , the null hypothesis is:H 0 : 12 = 13 . . . = 45 = 0, aga<strong>in</strong>st the alternative hypothesis,H 1 : at least one covariance is nonzero.In our three equations, the test statistic is: = N(r 2 12 + r 2 13 +…r 2 45), where r 2 ij is the squared correlation,r 2 ij = 2 ij / ii jj .Under H 0 , has an asymptotic 2 distribution with five degrees <strong>of</strong> freedom. I may reject H 0for a value <strong>of</strong> greater than the critical value from a 2 (45) distribution (i.e. with 45 degrees <strong>of</strong>freedom) for a specified significance level. In this study, the calculated 2 value for Sweden


Us<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong> for Neighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway 107<strong>and</strong> Norway together is equal to 100 (p-value = 0.000). This result, reported <strong>in</strong> Table 1 belowfor Sweden <strong>and</strong> Norway together, suggests a rejection <strong>of</strong> H 0 at any conventional significancelevel. This implies that the residuals from each ISUR regressions are significantly positivelyor negatively correlated with each other that might st<strong>and</strong> for the relation between theseequations <strong>and</strong> the countries thereafter. Also this can show substitutability <strong>and</strong>complementarity among dest<strong>in</strong>ations by <strong>in</strong>dicat<strong>in</strong>g positive <strong>and</strong> negative correlation <strong>of</strong>residuals. Clear conclusions about the complementarily or substitutability amongdest<strong>in</strong>ations are not usually obta<strong>in</strong>ed <strong>in</strong> studies us<strong>in</strong>g the correlation matrix <strong>of</strong> residuals <strong>and</strong>SUR model.Dn/s UK/s Swit/s Jp/s US/s Dn/n UK/n Swt/n JP/n US/nDn/s 1.0000UK/s 0.0269 1.000SWIT/s 0.2497 -0.1475 1.000JP/s -0.0284 0.1550 0.0094 1.000US/s -0.1465 -0.0940 0.1320 0.0389 1.000DN/n -0.0909 0.0829 -0.0716 -0.0579 0.0650 1.000UK/n 0.0335 -0.1719 0.1384 -0.0985 -0.0632 -0.0216 1.000SWIT/n 0.0876 0.0534 0.0999 -0.0606 0.0350 0.0231 0.1036 1.000JP/n 0.0195 -0.0235 0.0236 -0.0828 0.2230 0.1444 -0.0414 0.1493 1.000US/n -0.1943 -0.1549 0.1279 -0.1170 -0.0330 -0.0081 0.3869 -0.0895 -0.0010 1.000Breusch-Pagan test <strong>of</strong> <strong>in</strong>dependence: chi2(45) = 100, Pr = 0.0000Table 1. Correlation matrix <strong>of</strong> residuals for Sweden <strong>and</strong> Norway:4. <strong>The</strong> ISUR resultsIn this section, we present the most important results from the ISUR method to model<strong>in</strong>ternational tourism dem<strong>and</strong> to SW:6 <strong>in</strong> Sweden <strong>and</strong> NWT <strong>in</strong> Norway.We first conduct s<strong>in</strong>gle equations estimation on model (10) for the five equations for Sweden<strong>and</strong> the five equations for Norway, separately. We specify these equations accord<strong>in</strong>g to abattery <strong>of</strong> diagnostic tests (see the Appendix). We then select the five most appropriateequations for Sweden <strong>and</strong> Norway <strong>and</strong> <strong>in</strong>clude them separately <strong>in</strong> ISUR estimationconsist<strong>in</strong>g <strong>of</strong> ten equations to achieve the best possible efficiency. We then discuss theresults for each country separately <strong>and</strong> also compare them together. We first present theresults for the three economic variables <strong>and</strong> then discuss the results for the seasonal dummyvariables (with December as the base month), followed by the lagged dependent variables.Note that the macro variables are <strong>in</strong> logarithmic form <strong>and</strong> so we can <strong>in</strong>terpret the estimatedparameters as elasticities. <strong>The</strong> estimated coefficients are <strong>in</strong>cluded even if they are notsignificant. For the dummy <strong>and</strong> lagged dependent variables, only coefficients significant atleast at the 10% level <strong>in</strong> the s<strong>in</strong>gle equation estimation are <strong>in</strong>cluded <strong>in</strong> the ISUR estimation.consist<strong>in</strong>g <strong>of</strong> ten equations to achieve the best possible efficiency. We then discuss theresults for each country separately <strong>and</strong> also compare them together. We first present theresults for the three economic variables <strong>and</strong> then discuss the results for the seasonal dummyvariables (with December as the base month), followed by the lagged dependent variables.Note that the macro variables are <strong>in</strong> logarithmic form <strong>and</strong> so we can <strong>in</strong>terpret the estimated


108Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applicationsparameters as elasticities. <strong>The</strong> estimated coefficients are <strong>in</strong>cluded even if they are notsignificant. For the dummy <strong>and</strong> lagged dependent variables, only coefficients significant atleast at the 10% level <strong>in</strong> the s<strong>in</strong>gle equation estimation are <strong>in</strong>cluded <strong>in</strong> the ISUR estimation.SwedenEquationsParameters Denmark UK Switzerl<strong>and</strong> Japan USConstant .0662(0.974) –5.732 (0.103) .879 (0.850) 16.210 (0.000) 1.288 (0.761)CPI –. 197 (0.0.024) 2.474 (0.047) 2.474 (0.070) –6.205 (0.000) -.1348 (0.688)EX 1.821 (0.285) 0.782 (0.462) –1.564 (0.013) 0.1923 (0.456) 0.140 (0.224)Rp -.167( 0.000 ) 0.458 (0.000) -2.250 (.000) -6.205 ( 0.004) -.135 ( 1.583)D1 .605 (0.000) -.367 (.000)D2 .638 ( 0.000) -.256 (.000) .1651 (.024) .1651 (.002 )D3 .271 ( 0.069) -.4119 (.000) .0887 (.000) .132 (.007)D4 -.397 ( 0.002) -.432 (.000) -.195 (.000) .165 (.107) -.235 (.000)D5 -1.04 ( 0.000) -.662 (.000) -.133 (.000) -.129 (.001) -.109 (.000)D6 -.230 (0 .000) -.063 (.231) .493 (.000) .106 (.023) .343 (.000)D7 .323 (0 .000) -.285 (.0000) .813 (.000)D8 -.373 ( 0.002) -.385 (.000) .479 (.000)D9 -.788 (0 .000) -.645 (.000) -.246 (.000)D10 -.823 ( 0.000) -.486 ( .000) -.343 (.000) -.251 (.012)D11 -.894 (0 .000) -.294 (.000) .314 (.000) 275 (.083) -.137 (.000)Y(t–1) .6056 (.000) 0.095 (0.082)Y(t–2)Y(t–3)Y(t–4) -.169 (.001)Y(t–11) .136 (.061) .116 (.032) .208 (.000) .551 (.001)Y(t–12) .0411 (.552) .275 (.000) .142 (.010) .594 (.000) .215 (.063)R2 0.941 0.900 0.824 0.845 0.742<strong>The</strong> non significant results erased from the Table.Table 2. ISUR estimation results for Sweden4.1 Results for SwedenTable 1 show that the CPI parameter for Denmark is negative <strong>and</strong> small <strong>in</strong> magnitude butnot statistically significant, <strong>in</strong>dicat<strong>in</strong>g Swedish CPI has no effect on the dem<strong>and</strong> for tourismby Denmark. This could be due to low travel costs, whereas countries <strong>of</strong> orig<strong>in</strong> that are moredistant generally have higher price elasticity. <strong>The</strong> estimated CPISW elasticity is –6.205 <strong>and</strong>greater than that for Japan. This <strong>in</strong>dicates that a 1% <strong>in</strong>crease <strong>in</strong> CPISW results <strong>in</strong> a 6.2%decrease <strong>in</strong> tourist arrivals to SW6 from Japan. <strong>The</strong> low CPISW elasticity (-0.13) for the UScould be a reflection <strong>of</strong> the depreciation <strong>of</strong> the Swedish Krona aga<strong>in</strong>st the US dollar.<strong>The</strong> estimated elasticity <strong>of</strong> the relative (substitute) price ranges from 6.2% to 0.13% <strong>and</strong> isgreater than one for Japan <strong>and</strong> Switzerl<strong>and</strong>. This <strong>in</strong>dicates that a 1% rise <strong>in</strong> the relative price


Us<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong> for Neighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway 109level (price <strong>of</strong> tourism <strong>in</strong> Sweden relative to Norway) causes more than 1% fall <strong>in</strong> touristarrivals from Japan <strong>and</strong> Switzerl<strong>and</strong>. <strong>The</strong>se estimates <strong>in</strong>dicate that tourist arrivals <strong>in</strong> Swedenfrom these countries are elastic with respect to the relative price variable. This implies thatSweden must ma<strong>in</strong>ta<strong>in</strong> its <strong>in</strong>ternational price competitiveness to ma<strong>in</strong>ta<strong>in</strong> high growth <strong>in</strong>tourist <strong>in</strong>flow. <strong>The</strong> estimated relative price level elasticity ranges from 0.2% to 0.8% <strong>and</strong> isless than one for Denmark <strong>and</strong> the US. <strong>The</strong>se suggest that a 1% <strong>in</strong>crease <strong>in</strong> the relative priceresults <strong>in</strong> a 0.2% <strong>and</strong> 0.1% decrease <strong>in</strong> tourist arrivals to SW6 from Denmark <strong>and</strong> the US,respectively. <strong>The</strong> low exchange rate elasticity for Japan, UK <strong>and</strong> the US may also be areflection <strong>of</strong> the depreciation <strong>of</strong> the Swedish krona aga<strong>in</strong>st the Japanese yen <strong>and</strong> US dollar.As expected, the estimated elasticities <strong>of</strong> CPI SW for the UK <strong>and</strong> Switzerl<strong>and</strong> are positive.Parameters Denmark UK Switzerl<strong>and</strong> Japan USConstant 1.848 (0.034) -2.235 (0.093) 643 (0.784 ) -1.964 (0.260) 2.337 (0.110)CPI -0.511 (0.256) 2.284 (0.001) 2.601 (0.000) 0.820 (0.272) –0.5252 (0.373)Ex 0.241 (0.685 ) –0.665 (0.048) -1.395 (0.092) – 0.463(0.121) 0.118 (0.579)Rp 0.204 ( 0.729) –1.375 (0.019) -1.615 (0.013) –0.994 (0.176) –0.5272 (0.365)D1 0.098 (0.056)D2 0.1549 (0.000) 0.122 (0.042)D3 0.158 (0.002) 0.210 (0.000) 0.161 (0.004)D4 –0.476 (0.000) 4D5 –0.135 (0.018) 0.495 (0.000) –0.161 (0.025) 0.357 (0.000)D6 0.308 (0.000) 0.473 (0.000) 1.334 (0.000) 0.235 (0.000) 0.487 (0.000)D7 0.265 (0.000) 0.443 (0.000) 1.334 (0.000) 0.441 (0.000)D8 0.721 (0.000) 0.419 (0.000)D9 –0.227 (0.000) 0.220 (0.001)D10 –0.331 (0.000) –0.284 (0.000) 0.172 (0.002)D11 –0.2136 (0.000)Y (t–1) 0.212 (0.000) 0.0137 (0.789) 0.1768 (0.000) 0.430 (0.000) 0.334 (0.000)Y (t–2) –0.157 (0.016)Y (t–3) –0.135 (0.001)Y (t–6) –0.116 (0.002) –0.183 (0.000)Y (t–7) 0.144 (0.000)Y (t–9) –0.127 (0.005)Y (t–10) –0.129 (0.002)Y (t–11) 0.278 (0.000) 0.187 (0.000) 4Y (t–12) 0.363 (0.000) 0.309 (0.000) 0.263 (0.000) 0.269 (0.000)R 2 0.924 0.793 0.950 0.808 0.850<strong>The</strong> non significant results erased from the Table.Table 3. ISUR estimation results for NorwayIn the case <strong>of</strong> the UK, we f<strong>in</strong>d that all dummies are significant, <strong>in</strong>dicat<strong>in</strong>g clear seasonality <strong>in</strong>the dem<strong>and</strong> for tourism. <strong>The</strong> dem<strong>and</strong> <strong>in</strong> December is the highest for the year. we also f<strong>in</strong>dlags 4 <strong>and</strong> 12 are statistically significant. Note that the sign <strong>of</strong> lag 4 is negative while it islarger <strong>and</strong> positive for lags 11 <strong>and</strong> 12. For Switzerl<strong>and</strong>, only the summer dummies are large,


110Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applicationspositive, <strong>and</strong> statistically significant, mean<strong>in</strong>g that the Swiss are relatively more <strong>in</strong>terested <strong>in</strong>summer tourism. <strong>The</strong> rema<strong>in</strong><strong>in</strong>g dummies are either <strong>in</strong>significant or small <strong>in</strong> magnitude.<strong>The</strong> estimated parameters <strong>of</strong> lags 1 <strong>and</strong> 12 are positive <strong>and</strong> significant.In general, the lags <strong>of</strong> the dependent variable for the months <strong>of</strong> January <strong>and</strong> December arealso significant, support<strong>in</strong>g the hypothesis <strong>of</strong> a habit-form<strong>in</strong>g or word-<strong>of</strong>-mouth effect. Some<strong>of</strong> the monthly dummies as proxies for seasonal effects are also significant, <strong>in</strong>clud<strong>in</strong>gJanuary, March, May, June, July, September, October, <strong>and</strong> November. Estimates <strong>of</strong> theDenmark dummy show a clear seasonal variation <strong>in</strong> the pattern <strong>of</strong> Danish tourism dem<strong>and</strong><strong>in</strong> Sweden, such that dem<strong>and</strong> <strong>in</strong> January, February, March, <strong>and</strong> July is higher than <strong>in</strong>December, with lower dem<strong>and</strong> <strong>in</strong> other months.4.2 Results for NorwayTable 3 provides estimates <strong>of</strong> the monthly arrivals from Denmark, Japan, <strong>and</strong> the US toNWT <strong>in</strong> Norway. <strong>The</strong> estimated Norwegian CPI (CPI Nor ) long- run elasticity ranges from0.5% to 0.8% <strong>and</strong> is lower than that for Denmark, Japan, <strong>and</strong> the US. <strong>The</strong> estimated CPI SWcoefficients suggest that a 1% <strong>in</strong>crease <strong>in</strong> CPI Nor results <strong>in</strong> 0.5%, 0.52%, <strong>and</strong> 0.8% decreases <strong>in</strong>tourist arrivals to Norway from Denmark, Japan, <strong>and</strong> the US, respectively. <strong>The</strong> low CPI Norelasticity for Japan <strong>and</strong> the US may be a reflection <strong>of</strong> the depreciation <strong>of</strong> the Norwegiankrone aga<strong>in</strong>st the Japanese yen <strong>and</strong> the US dollar.<strong>The</strong> estimated long run elasticities <strong>of</strong> the relative price variable for Denmark <strong>and</strong> the US areless than one (0.2% <strong>and</strong> 0.6%, respectively), <strong>in</strong>dicat<strong>in</strong>g that a 1% rise <strong>in</strong> the relative price(price <strong>of</strong> tourism <strong>in</strong> Norway relative to Sweden) causes about a 1% fall <strong>in</strong> tourist arrivalsfrom Denmark <strong>and</strong> the US. <strong>The</strong> estimated long run –run elasticity <strong>of</strong> the relative price forJapan is closed to unity (99%), which <strong>in</strong>dicates that a 1% rise <strong>in</strong> the relative price (price <strong>of</strong>tourism <strong>in</strong> Norway relative to Sweden) causes around a 1% drop <strong>in</strong> tourist arrivals fromJapan. <strong>The</strong> estimated long- run elasticity <strong>of</strong> the relative price variable for the UK <strong>and</strong>Switzerl<strong>and</strong> are greater than one, <strong>in</strong>dicat<strong>in</strong>g that the arrival <strong>of</strong> tourists <strong>in</strong> Norway from thesecountries is elastic with respect to the relative price variable. This implies that Norway mustalso ma<strong>in</strong>ta<strong>in</strong> its <strong>in</strong>ternational price competitiveness to ma<strong>in</strong>ta<strong>in</strong> high growth <strong>in</strong> tourist<strong>in</strong>flow. Yet aga<strong>in</strong>, the low exchange rate long- run elasticity for Denmark, Japan, <strong>and</strong> the UScan be a reflection <strong>of</strong> the depreciation <strong>of</strong> the Norwegian krona aga<strong>in</strong>st the Danish krona, theJapanese yen, <strong>and</strong> the US dollar.5. Summary <strong>and</strong> remarksThis chapter has applied the ISUR model, a model not used <strong>in</strong> other studies that haveestimated models for tourism to these two neighbour<strong>in</strong>g regions. First, the model wasapplied to the neighbour<strong>in</strong>g dest<strong>in</strong>ations for the period <strong>of</strong> transition from characteristics <strong>of</strong> alower level <strong>of</strong> <strong>in</strong>tegration <strong>and</strong> <strong>of</strong> fac<strong>in</strong>g competition from other countries, to characteristics<strong>of</strong> a high level <strong>of</strong> <strong>in</strong>tegration, globalization, exposure to an <strong>in</strong>ternational competitive market,<strong>and</strong> high levels <strong>of</strong> <strong>in</strong>come <strong>and</strong> welfare.Second, the model allowed for comparison <strong>of</strong> the changes <strong>in</strong> the behaviour <strong>of</strong> tourismdem<strong>and</strong> <strong>in</strong> each country over time, not only <strong>in</strong> terms <strong>of</strong> the number <strong>of</strong> visitors, price <strong>and</strong>exchange rate, but also <strong>of</strong> relative price elasticities. <strong>The</strong> estimated results show the model tobe consistent with the data, as <strong>in</strong>dicated by both the diagnostic statistic <strong>and</strong> the model’sgood forecast<strong>in</strong>g ability. Moreover, the results are consistent with the properties <strong>of</strong>


Us<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong> for Neighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway 111homogeneity <strong>and</strong> symmetry. This accords with the microeconomic foundations <strong>of</strong> the model<strong>and</strong> <strong>in</strong>creases the credibility <strong>of</strong> the elasticity values.Substitutability <strong>and</strong> complementarity among dest<strong>in</strong>ations are <strong>in</strong>dicated by positive <strong>and</strong>negative relative price elasticities, respectively. Clear conclusions about thecomplementarity or substitutability among dest<strong>in</strong>ations are not usually obta<strong>in</strong>ed <strong>in</strong> studiesus<strong>in</strong>g the ISUR model, which have produced few well def<strong>in</strong>ed relative price effects.However, the results <strong>in</strong> this study seem consistent <strong>and</strong> also co<strong>in</strong>cide with a prioriexpectations. Hence they are taken as an <strong>in</strong>dication <strong>of</strong> the relative magnitudes <strong>and</strong>directions <strong>of</strong> changes <strong>in</strong> dem<strong>and</strong>.<strong>The</strong> ma<strong>in</strong> purpose <strong>of</strong> this chapter is to estimate the dem<strong>and</strong> for tourism to two neighbour<strong>in</strong>gregions <strong>in</strong> Sweden <strong>and</strong> Norway from five different countries: namely, Denmark, the UK,Switzerl<strong>and</strong>, Japan, <strong>and</strong> the US. Monthly time series data from 1993:01 to 2006:12 is collectedfrom Statistics Sweden for this purpose. For each visit<strong>in</strong>g country, We specify a separateequation with the relevant <strong>in</strong>formation <strong>in</strong>cluded <strong>in</strong> each equation. We conduct severaldiagnostic tests <strong>in</strong> order to specify the five equations for SW:6 <strong>in</strong> Sweden <strong>and</strong> NWT <strong>in</strong>Norway. We then estimate these equations us<strong>in</strong>g Zellner’s ISUR, which takes <strong>in</strong>toconsideration any possible correlation between the equations <strong>and</strong> hence is more efficientthan other s<strong>in</strong>gle equation estimation methods, such as OLS.<strong>The</strong> results also <strong>in</strong>dicates that CPI, some lagged dependent variables, <strong>and</strong> several monthlydummy variables represent<strong>in</strong>g seasonal effects have a significant impact on the number <strong>of</strong>visitors to SW6 <strong>in</strong> Sweden <strong>and</strong> NWT <strong>in</strong> Norway. <strong>The</strong> results also show that the relative price<strong>and</strong> exchange rate have a significant effect on <strong>in</strong>ternational tourism dem<strong>and</strong> for somecountries. However, although we could view this conclusion as support<strong>in</strong>g a theoreticalframework that describes tourism dem<strong>and</strong> model variable relationships, our dem<strong>and</strong>system lacks a travel cost variable. Nonetheless, our results could also have importantimplications for the decision-mak<strong>in</strong>g process <strong>of</strong> government tourism agencies <strong>in</strong> bothcountries when consider<strong>in</strong>g <strong>in</strong>fluential factors <strong>in</strong> their long run plann<strong>in</strong>g.6. Appendix6.1 Diagnostic tests6.1.1 <strong>The</strong> Cusum testThis test is used for time series <strong>and</strong> checks for structural changes. In the Cusum testRecursive Residuals (RR) calculated by the Kalman Filter are used.I now describe the construction <strong>of</strong> recursive residuals <strong>and</strong> the Kalman filter technique. <strong>The</strong>recursive residuals can be computed by forward or backward recursion. Only forwardrecursion is described, backward recursion be<strong>in</strong>g analogous.Given N observations, consider the l<strong>in</strong>ear model (2 . 2 . 1) but with the correspond<strong>in</strong>gvector <strong>of</strong> coefficient expressed as t , imply<strong>in</strong>g that the coefficients may vary over time t.<strong>The</strong> hypothesis to be tested is = = , . . ., = = . <strong>The</strong> OLS estimator based on Nobservations is:b = ( X'X ) -1 X'y ,where X is a N by k matrix <strong>of</strong> observations on the regressors, <strong>and</strong> y is an N by 1 vector <strong>of</strong>observations for the dependent variable. Suppose that only r observations are used toestimate . <strong>The</strong>n for r > k, where k is the number <strong>of</strong> <strong>in</strong>dependent variables,


112Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applicationsb r = ( X r 'X r ) -1 X r 'y r ,r = k+1, . . ., N .Us<strong>in</strong>g b r , one may "forecast" y r at sample po<strong>in</strong>t r, correspond<strong>in</strong>g to the vector X r <strong>of</strong> theexplanatory variables at that po<strong>in</strong>t.Recursive residuals are now derived by estimat<strong>in</strong>g equation (2 . 2 . 1) recursively <strong>in</strong> the samemanner, that is by us<strong>in</strong>g the first k observations to get an <strong>in</strong>itial estimate <strong>of</strong> , <strong>and</strong> thengradually enlarg<strong>in</strong>g the sample, add<strong>in</strong>g one observation at a time <strong>and</strong> re-estimat<strong>in</strong>g ateach step. In this way, it is possible to get (N-k) estimates <strong>of</strong> the vector , <strong>and</strong>correspond<strong>in</strong>gly (N-k-1) forecast errors <strong>of</strong> the type:Wr yr Xrbr 1r = k+1, . . ., Nwhere b r-1 is an estimate <strong>of</strong> based on the first r - 1 observations. It can be shown that,under the null hypothesis, these forecast errors have mean zero <strong>and</strong> variance 2 d r2, whered r is a scalar function <strong>of</strong> the explanatory variables, equal to [ 1 + X r '(X' r-1 X r-1 ) -1 X r ] 1/2 .<strong>The</strong>n the quantity:y X bWr[1 X ( X X ) X ]r r r1' ' 1/2r r1 r1)rr = k+1, . . ., Ngives a set <strong>of</strong> st<strong>and</strong>ardized prediction errors, called "recursive residuals". <strong>The</strong> recursiveresiduals are <strong>in</strong>dependently <strong>and</strong> normally distributed with mean zero <strong>and</strong> constant variance 2 . As a result <strong>of</strong> a change <strong>in</strong> the structure over time, these recursive residuals will no longerhave zero mean, <strong>and</strong> the CUSUM <strong>of</strong> these residuals can be used to test for structural change.CUSUM <strong>in</strong>volves the plot <strong>of</strong> the quantity:rV W / *rtk1r = k+1, . . ., N,where * is the estimated st<strong>and</strong>ard deviation based on the full sample.<strong>The</strong> test f<strong>in</strong>ds parameter <strong>in</strong>stability if the cumulative sum goes outside the area between thetwo error bounds. Thus, movements <strong>of</strong> V t outside the error bounds are a sign <strong>of</strong> parameter<strong>in</strong>stability.6.1.2 <strong>The</strong> Breusch-Godfrey-test<strong>The</strong> Breusch-Godfrey test can be separated <strong>in</strong>to several stages:1. Run an OLS on:y X y it t ti tt


Us<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong> for Neighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway 113This gives us ˆt 2. Run an OLS on:ˆ X y ˆ ˆ ... ˆ uit t ti 1 t1 2 t2P tP tThis equation can be used for any AR(P) process. From this equation the unrestrictedresidual sum <strong>of</strong> squares (RSS u ).<strong>The</strong> restricted residual sum <strong>of</strong> squares (RSS R ) is given from the follow<strong>in</strong>g equation:<strong>The</strong> null hypothesis is:3. Run an F-test: Xy ˆt t t 1t: .... 0H0 1 2 PF=((RSS R -RSS U )/p) / (RSS U /(T-k-P))This has a distribution: F(P,T-k-P) under the null hypothesis.<strong>The</strong> Breusch-Godfrey test can be tested for AR(P) processes which gives this test a clearadvantage over other available tests for autocorrelation.6.1.3 <strong>The</strong> Ramsey RESET-testRESET test st<strong>and</strong>s for Regression Specification Error Test. <strong>The</strong> test is very general <strong>and</strong> canonly tell you if you have a problem or not. It tests for omitted variables <strong>and</strong> <strong>in</strong>correctfunctional forms or misspecified dynamics <strong>and</strong> also if there is a correlation between theerror term <strong>and</strong> the <strong>in</strong>dependent variable. <strong>The</strong> null hypothesis is:H 0 : E (ε i /X i ) = 0H 1 : E (ε i /X i ) ≠ 0(<strong>and</strong> an omitted variable effect is present)Thus, by reject<strong>in</strong>g the null hypothesis <strong>in</strong>dicates some type <strong>of</strong> misspecification. First a l<strong>in</strong>earregression is specified:y X i i iThis gives the restricted residual sum <strong>of</strong> squares (RSSR). After the RSS R has been found theunrestricted model is presented by add<strong>in</strong>g variables (three fitted values):y X yˆyˆu2 3t i 1 i 2i tThis gives us the unrestricted residual sum <strong>of</strong> squares (RSS U ). In the third step the RESETtestuses a F-test:F= ((RSS R - RSS U )/number <strong>of</strong> restrictions under H 0 ) / (RSS U / (N- number <strong>of</strong> parameters <strong>in</strong>unrestricted model))<strong>The</strong> F-test checks if θ 1 =θ 2 =0, if θ 1 =θ 2 ≠0 I have an omitted variable or a misspecification <strong>in</strong>the model.


114Advances <strong>in</strong> Econometrics - <strong>The</strong>ory <strong>and</strong> Applications6.1.4 <strong>The</strong> White’s testThis test is a general test where I do not need to make any specific assumptions regard<strong>in</strong>gthe nature <strong>of</strong> the heteroscedasticity, whether it is <strong>in</strong>creas<strong>in</strong>g, decreas<strong>in</strong>g etc. <strong>The</strong> test onlytells us if I have an <strong>in</strong>dication <strong>of</strong> heteroscedasticity.2 20 : iH i<strong>The</strong> alternative hypothesis is not H 0 , anyth<strong>in</strong>g other than H 0 .<strong>The</strong> test can be divided <strong>in</strong>to several steps:1. Run an OLS on:y 1X1 ... X i i k ki iFrom this equation I get ˆi which is used as a proxy for the variance.2. Run an OLS on:ˆ ... ... 2 2 2i 0 1X1i kXki k1X1i kkXkk kk1X1iXk iWhere k is the number <strong>of</strong> parameters. <strong>The</strong> variance is considered to be a l<strong>in</strong>ear function <strong>of</strong> anumber <strong>of</strong> <strong>in</strong>dependent variables, their quadratic <strong>and</strong> cross products. Thus, the X:s is usedas a proxy for Z.3. Calculate an F-test:Restricted model:2 ' 'ˆi 0 i From this test the restricted residual sum <strong>of</strong> squares (RSS R ) is measured.<strong>The</strong> F-test is:WhereF=((RSS R -RSS U )/k) / (RSS U /(n-k-1))H0 : i 0 i1,2... k6.1.5 <strong>The</strong> ARCH Engel’s LM testThis is a test for AutoRegressive Conditional Heteroscedasticity (ARCH). <strong>The</strong> ARCHprocess can be modeled as:y X t t twhere the Variance <strong>of</strong> t conditioned on t i: Var( t \ t i ) = 0 + 1 t i1. Use OLS on the orig<strong>in</strong>al model <strong>and</strong> get: ˆt . Square it <strong>and</strong> use it <strong>in</strong> the follo<strong>in</strong>gunrestricted model:2 22. ˆ ˆt 0+ itii+t3. Test whether i = 0, for any i = 1, 2 , . . . By an F-test as before.2


Us<strong>in</strong>g the SUR Model <strong>of</strong> Tourism Dem<strong>and</strong> for Neighbour<strong>in</strong>g Regions <strong>in</strong> Sweden <strong>and</strong> Norway 1156.1.6 Test for non-normality<strong>The</strong> test for non-normality is normally done before one test for heteroskedasticity <strong>and</strong>structural changes.<strong>The</strong> test used here for test<strong>in</strong>g for normal distribution is the Jarque-Bera test. <strong>The</strong> Jarque-Beratest is structured as follows:2 2T1/6bˆˆ1 1/24( b23)3/21 3/( 2)b 22 4 /( 2)b Where T is the total number <strong>of</strong> observations, b 1 is a measure for skewness <strong>and</strong> b 2 is ameasure for kurtosis. <strong>The</strong> μ are different moments. <strong>The</strong> test has a chi-square distributionwith two degrees <strong>of</strong> freedom under the null hypothesis <strong>of</strong> normal distribution. <strong>The</strong> twodegrees <strong>of</strong> freedom comes from hav<strong>in</strong>g one for skewness <strong>and</strong> one for kurtosis.7. ReferencesAndersson, K. <strong>and</strong> Berg, C. (1995), <strong>The</strong> <strong>in</strong>flation target <strong>in</strong> Sweden. In A.G. Haldane (ed.)Target<strong>in</strong>g <strong>in</strong>flation. London: Bank <strong>of</strong> Engl<strong>and</strong>Breusch, T. S. (1978): Test<strong>in</strong>g for Autocorrelation <strong>in</strong> Dynamic L<strong>in</strong>ear Models, AustralianEconomic Papers 17, 334-355.Breusch, T. S. <strong>and</strong> Pagan, A. R. (1980): <strong>The</strong> Lagrange-Multiplier Test <strong>and</strong> Its Applications toModel Specification <strong>in</strong> Econometrics, Review <strong>of</strong> Economics Studies, 47, 239-253.Brown, R. L., Durb<strong>in</strong>, J., <strong>and</strong> Evans, J. M. (1975): Techniques for Test<strong>in</strong>g the Constancy<strong>of</strong>Regression Relationships over Time, Journal <strong>of</strong> the Royal Statistical Society,37,149-192.Godfrey, L. G. (1978): Test<strong>in</strong>g for Higher Order Serial Correlation <strong>in</strong> RegressionEquationsWhen the Regressors Include Lagged Dependent Variables, Econometrica,46,1303-1310.Godfrey, L. G. (1988): Misspecification Tests <strong>in</strong> Econometrics, Cambridge: CambridgeUniversity Press.Grouch, G.I, (1992): Effect <strong>of</strong> <strong>in</strong>come <strong>and</strong> price on <strong>in</strong>ternational tourism to Australia,TourismManagement, June, 196-208.Gunadhi, H. <strong>and</strong> Boey, C. (1986) Dem<strong>and</strong> elasticities <strong>of</strong> tourism <strong>in</strong> S<strong>in</strong>gapore, TourismManagement, 7, 239 -53Jarque, C. M., <strong>and</strong> Bera, A. K. (1987): A Test for Normality <strong>of</strong> Observations <strong>and</strong>RegressionResiduals, International Statistical Review 55, 163-172.Kulendran, N. (196) Modell<strong>in</strong>g Quarterly tourist flow to Australia us<strong>in</strong>gco<strong>in</strong>tegrationanalysis. TourismEconomic 2 (3), 203-22.Lathiras,P.<strong>and</strong> Sirioopulos, C.(1998), <strong>The</strong> dem<strong>and</strong> for a a tourism to Greece: A co<strong>in</strong>tegration approach. TourismEconomics 171-281.Ramsey, J. B. (1969): Test for Specification error <strong>in</strong> Classical L<strong>in</strong>ear Least Squares RegressionAnalysis, Journal <strong>of</strong> the Royal Statistical Society (b, 31, 350-371.


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