Efficiency in Banking: Empirical Evidence from the Savings ... - Ivie
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<strong>Efficiency</strong> <strong>in</strong> Bank<strong>in</strong>g: <strong>Empirical</strong> <strong>Evidence</strong> <strong>from</strong> <strong>the</strong> Sav<strong>in</strong>gs<br />
Banks Sector<br />
S. Carbo a , E.P.M. Gardener b , and J. Williams b<br />
a<br />
Facultad de Ciencas Economicas y Empresariales, University of Granada, Spa<strong>in</strong><br />
b Institute of European F<strong>in</strong>ance, University of Wales, Bangor, Gwynedd LL57 2DG, UK.<br />
Abstract<br />
This study aims to contribute to <strong>the</strong> established literature by us<strong>in</strong>g <strong>the</strong> Fourier Flexible<br />
functional form and stochastic cost frontier methodologies to estimate scale economies<br />
and X-<strong>in</strong>efficiencies for a large sample of European sav<strong>in</strong>gs banks between 1989 and<br />
1996. In <strong>the</strong>ir extensive review of <strong>the</strong> bank efficiency literature, Berger and Humphrey<br />
(1997) note that <strong>the</strong> volume of European studies has not matched that of <strong>the</strong> US and<br />
<strong>the</strong>re exists a paucity of cross-country studies. Whereas scale economies are widespread<br />
and positively related to bank size, we f<strong>in</strong>d no evidence of a significant relationship<br />
between size and X-efficiency. Generally, scale economies are found to range between<br />
7 and 10 percent, while X-<strong>in</strong>efficiency measures appear to be much larger, around 22<br />
percent. These results suggest that European sav<strong>in</strong>gs banks can obta<strong>in</strong> cost reductions<br />
through reduc<strong>in</strong>g managerial and o<strong>the</strong>r <strong>in</strong>efficiencies and also by <strong>in</strong>creas<strong>in</strong>g <strong>the</strong> scale of<br />
production.<br />
JEL Classification: G21<br />
Keywords: Bank<strong>in</strong>g; Stochastic cost frontier; X-efficiency; Economies of scale.<br />
Correspond<strong>in</strong>g author: Jonathan Williams, Institute of European F<strong>in</strong>ance, University of Wales, Bangor,<br />
Gwynedd, LL57 2DG, United K<strong>in</strong>gdom. E-mail: jon.williams@bangor.ac.uk
1. Introduction<br />
Sav<strong>in</strong>gs banks are an important part of <strong>the</strong> European bank<strong>in</strong>g system account<strong>in</strong>g<br />
for around 20% of bank<strong>in</strong>g system assets. In terms of customer deposits, sav<strong>in</strong>gs banks<br />
are even stronger with some national sectors hold<strong>in</strong>g over 30% and 40% market share<br />
(European Sav<strong>in</strong>gs Banks Group, 1997). Although <strong>the</strong>ir roots lie <strong>in</strong> retail bank<strong>in</strong>g,<br />
sav<strong>in</strong>gs banks have typically evolved to full-service banks that are virtually<br />
<strong>in</strong>dist<strong>in</strong>guishable <strong>from</strong> <strong>the</strong>ir commercial bank competitors (Gardener et al, 1997). As<br />
such, sav<strong>in</strong>gs banks are subject to those same competitive forces (and deregulatory<br />
processes) that have and are shap<strong>in</strong>g <strong>the</strong> EU bank<strong>in</strong>g system.<br />
One feature that still differentiates <strong>the</strong> majority of sav<strong>in</strong>gs banks <strong>from</strong><br />
commercial banks is <strong>the</strong>ir organisational form. Sav<strong>in</strong>gs banks typically began as mutual<br />
<strong>in</strong>stitutions and some operate with a significant level of state <strong>in</strong>volvement. Competitive<br />
pressures like <strong>the</strong> need to realise capital adequacy requirements have led to some<br />
sav<strong>in</strong>gs banks sectors be<strong>in</strong>g restructured 1 . In o<strong>the</strong>r sectors <strong>the</strong>re is pressure to demutualise<br />
and, <strong>in</strong>deed, convert <strong>in</strong>to jo<strong>in</strong>t stock <strong>in</strong>stitutions 2 . Yet, <strong>the</strong>re is no<br />
requirement for sav<strong>in</strong>gs banks to operate under any particular organisational structure,<br />
provid<strong>in</strong>g EU competition law is not violated (Ehlermann, 1992) 3 .<br />
The importance of evaluat<strong>in</strong>g <strong>the</strong> efficiency of sav<strong>in</strong>gs banks is emphasised by<br />
Köhler (1996, p. 7) who states that 'The sav<strong>in</strong>gs banks of today are bus<strong>in</strong>ess concerns<br />
1 The French sav<strong>in</strong>gs banks sector, for example, was reconfigured <strong>in</strong> June 1991 with <strong>the</strong> result that <strong>the</strong><br />
number of sav<strong>in</strong>gs banks reduced <strong>from</strong> over 180 to 35. The new number of French sav<strong>in</strong>gs banks<br />
corresponds to <strong>the</strong> 31 French regions and 4 overseas dependencies.<br />
2 The conversion of four previously mutual UK build<strong>in</strong>g societies <strong>in</strong> 1997 provides such an example.<br />
3 Post-1980, national policies and EU directives aimed to facilitate a more open and competitive<br />
environment for banks. European law, however, considers <strong>the</strong> operations and functions of enterprises.<br />
Provid<strong>in</strong>g that competition law is not violated, <strong>the</strong> law does not differentiate between or confer certa<strong>in</strong><br />
advantages upon companies organised under private law as opposed to those belong<strong>in</strong>g to <strong>the</strong> public,<br />
cooperative, mutual and non-profit sectors (Ehlermann, 1992).<br />
2
which have to stand up to competition through efficient bus<strong>in</strong>ess management and<br />
sound earn<strong>in</strong>g capacity'. The Commission of <strong>the</strong> European Communities (1988) has<br />
stressed <strong>in</strong> its 1992 s<strong>in</strong>gle market programme that substantial benefits would accrue to<br />
those sectors that can benefit <strong>from</strong> positive supply-side effects. In particular, 'price<br />
reductions occasioned by competitive pressures will force firms to look actively for<br />
reduction <strong>in</strong> costs through <strong>the</strong> elim<strong>in</strong>ation of areas of low productivity and/or by a<br />
greater exploitation of scale economies' (European Economy, 1988, p.162).<br />
In <strong>the</strong>ir extensive review of <strong>the</strong> bank efficiency literature, Berger and Humphrey<br />
(1997) note that <strong>the</strong> volume of European studies has not matched that of <strong>the</strong> US and<br />
<strong>the</strong>re exists a paucity of cross-country studies. Despite <strong>the</strong> managerial objective to<br />
improve efficiency, only a handful of studies have <strong>in</strong>vestigated <strong>the</strong> cost characteristics of<br />
European bank<strong>in</strong>g markets. The present study aims to advance <strong>the</strong> established literature<br />
by us<strong>in</strong>g <strong>the</strong> Fourier Flexible functional form and stochastic cost frontier approach <strong>in</strong><br />
order to evaluate evidence of scale and X-<strong>in</strong>efficiencies across <strong>the</strong> European sav<strong>in</strong>gs<br />
banks sector between 1989 and 1996.<br />
We f<strong>in</strong>d that scale economies are widespread across different countries and <strong>the</strong>y<br />
<strong>in</strong>crease with bank size. In general, scale economies are found to range between 7 and<br />
10 percent, while X-<strong>in</strong>efficiency measures appear to be much larger, around 22 percent.<br />
These results suggest that European sav<strong>in</strong>gs banks can obta<strong>in</strong> cost reductions through<br />
reduc<strong>in</strong>g managerial and o<strong>the</strong>r <strong>in</strong>efficiencies and also by <strong>in</strong>creas<strong>in</strong>g <strong>the</strong> scale of<br />
production. Overall, large sav<strong>in</strong>gs banks have scale economy advantages over <strong>the</strong>ir<br />
smaller counterparts. However, size does not appear to confer advantages <strong>in</strong> terms of<br />
X-efficiency. Given that larger banks realise greater scale economies this is likely to be<br />
an important factor promot<strong>in</strong>g consolidation <strong>in</strong> <strong>the</strong> European sav<strong>in</strong>gs banks <strong>in</strong>dustry.<br />
3
2. <strong>Efficiency</strong> <strong>in</strong> Bank<strong>in</strong>g - A Brief Literature Review<br />
Over recent years <strong>the</strong> structure of European bank<strong>in</strong>g has been chang<strong>in</strong>g rapidly<br />
and a primary motivation has been <strong>the</strong> drive for greater efficiency. A substantial US<br />
literature has emerged (for example, see Berger et al. (1993), Karapakis et al. (1994),<br />
Mester (1996), Mitchell and Onvural (1996)) which f<strong>in</strong>ds that X-efficiencies, brought<br />
about by superior management, improved technologies and o<strong>the</strong>r factors, exceed those<br />
efficiencies result<strong>in</strong>g <strong>from</strong> scale and scope economies. For <strong>in</strong>stance, Berger et al. (1993)<br />
note that scale and product-mix <strong>in</strong>efficiencies 'when accurately estimated', are usually<br />
found to account for less than 5 percent of costs. Berger and Humphrey (1997) show<br />
that out of 122 studies, <strong>the</strong> 60 that use parametric techniques f<strong>in</strong>d f<strong>in</strong>ancial firm X-<br />
<strong>in</strong>efficiencies averag<strong>in</strong>g around 15% (compared with 28% for non-parametric<br />
estimates). (Also Berger and Mester (1997) have found that average cost <strong>in</strong>efficiency <strong>in</strong><br />
US banks tended to decrease <strong>in</strong> <strong>the</strong> early 1990’s to around 13%.) Overall, however, <strong>the</strong><br />
general consensus <strong>from</strong> <strong>the</strong> literature is that banks will be more effective <strong>in</strong> reduc<strong>in</strong>g<br />
<strong>the</strong>ir costs by emulat<strong>in</strong>g best cost practice (reduc<strong>in</strong>g X-<strong>in</strong>efficiencies) ra<strong>the</strong>r than<br />
<strong>in</strong>creas<strong>in</strong>g size (scale economies) or diversify<strong>in</strong>g (scope economies).<br />
European research on cost efficiency <strong>in</strong> <strong>the</strong> bank<strong>in</strong>g sector has not matched <strong>the</strong><br />
volume of US studies and <strong>the</strong>re have been only a few cross-country studies 4 . The<br />
majority of European studies have focused on <strong>the</strong> issue of scale and scope economies <strong>in</strong><br />
<strong>in</strong>dividual countries and for particular types of banks. More recent literature has<br />
attempted to evaluate X-<strong>in</strong>efficiencies <strong>in</strong> various European bank<strong>in</strong>g markets. The<br />
earliest researchers used Cobb-Douglas and CES cost function methodologies to model<br />
4 As identified by Berger and Humphrey (1997).<br />
4
underly<strong>in</strong>g cost functions, whereas <strong>from</strong> <strong>the</strong> mid-1980s onwards most studies have used<br />
<strong>the</strong> translog functional form to estimate <strong>the</strong> cost characteristics of <strong>the</strong> bank<strong>in</strong>g <strong>in</strong>dustry.<br />
For a comprehensive review of <strong>the</strong> European literature on scale and scope economies<br />
and X-<strong>in</strong>efficiency see Molyneux et al. (1996, chapter 9). Overall, this literature tends<br />
to f<strong>in</strong>d widespread evidence of scale economies <strong>in</strong> various European bank<strong>in</strong>g markets,<br />
typically rang<strong>in</strong>g between 5% and 10% whilst X-<strong>in</strong>efficiencies are around 20-25%.<br />
Aga<strong>in</strong>, this general f<strong>in</strong>d<strong>in</strong>g is confirmed <strong>in</strong> <strong>the</strong> EC (1997) study that found mixed<br />
evidence on <strong>the</strong> level of scale economies while X-<strong>in</strong>efficiencies were estimated to be<br />
around 25%.<br />
In a recent paper Vennet (1998), uses <strong>the</strong> translog methodology to compare <strong>the</strong><br />
cost and profit efficiencies of European universal and specialist banks. Us<strong>in</strong>g a sample<br />
of 2,375 EU banks <strong>from</strong> 17 countries for <strong>the</strong> years 1995 and 1996 he f<strong>in</strong>ds that f<strong>in</strong>ancial<br />
conglomerates are more revenue efficient than <strong>the</strong>ir specialised competitors and that<br />
both cost and profit efficiency are higher <strong>in</strong> universal compared with non-universal<br />
banks. Mean levels of <strong>in</strong>efficiency are 30% for estimates that use traditional<br />
<strong>in</strong>termediation outputs (loans and securities) and 20% for estimates that <strong>in</strong>clude nontraditional<br />
outputs (<strong>in</strong>terest revenue and non-<strong>in</strong>terest revenue). For diversified banks,<br />
<strong>in</strong>efficiency appeared to be uncorrelated with size; however, small specialised banks<br />
appeared to be relatively <strong>in</strong>efficient compared with <strong>the</strong>ir larger counterparts 5 .<br />
While <strong>the</strong>re is an emerg<strong>in</strong>g literature on <strong>the</strong> cost efficiency of banks <strong>in</strong> <strong>the</strong><br />
5 Vennet’s results on cost efficiency were found to be broadly <strong>in</strong> accordance with Allen and Rai’s (1996)<br />
cross-country comparison of universal versus specialist bank<strong>in</strong>g systems. Scale economies were only<br />
found for <strong>the</strong> smallest banks, those with assets under ECU 10 billion, with constant return <strong>the</strong>reafter and<br />
diseconomies for <strong>the</strong> largest banks (assets exceed<strong>in</strong>g ECU 100 billion). Vennet (1998) suggests that this<br />
f<strong>in</strong>d<strong>in</strong>g would suggest that <strong>the</strong> bank sizes for which no diseconomies are found are higher than <strong>in</strong> <strong>the</strong><br />
1980’s, a result that was also reported for US banks by Berger and Mester (1997).<br />
5
mutual sector <strong>in</strong> various European countries (see, for example, Lang and Welzel 1996,<br />
and Grifell-Tatje and Lovell 1996), <strong>the</strong> most comprehensive studies appear to be on <strong>the</strong><br />
UK build<strong>in</strong>g societies sector (see, for example, Drake and Weyman-Jones 1996,<br />
McKillop and Glass 1994 and Glass and McKillop 1999) 6 . The aforementioned UK<br />
studies use both parametric and non-parametric methods. McKillop and Glass (1994)<br />
use a hybrid translog cost function to obta<strong>in</strong> estimates of overall and augmented<br />
economies of scale, <strong>in</strong>put-specific economies of scale, product-specific economies of<br />
scale and economies of scope. They found evidence of significant augmented<br />
economies of scale both for national and local build<strong>in</strong>g societies, but only constant<br />
returns to scale for regional build<strong>in</strong>g societies. In terms of augmented <strong>in</strong>put-specific<br />
economies of scale, unit cost sav<strong>in</strong>gs associated with <strong>the</strong> <strong>in</strong>creased use of physical<br />
capital were found for national societies but not for regional societies. Cost<br />
<strong>in</strong>efficiencies were found to exist for local and regional build<strong>in</strong>g societies <strong>in</strong> mortgage<br />
and non-mortgage product areas. There was apparently no evidence of economies of<br />
scope.<br />
Us<strong>in</strong>g data <strong>from</strong> 1988, Drake and Weyman-Jones (1996) use both parametric<br />
and non-parametric techniques, and found that <strong>in</strong>efficiency <strong>in</strong> <strong>the</strong> build<strong>in</strong>g society sector<br />
was <strong>in</strong> <strong>the</strong> region of 12%-13%. Glass and McKillop (1999) use l<strong>in</strong>ear programm<strong>in</strong>g<br />
techniques and Malmquist productivity <strong>in</strong>dices to estimate total productivity change <strong>in</strong><br />
<strong>the</strong> build<strong>in</strong>g society sector between 1989 and 1993. Total productivity change is<br />
decomposed <strong>in</strong>to efficiency change and technical change: <strong>the</strong> former be<strong>in</strong>g fur<strong>the</strong>r<br />
6 We have <strong>in</strong>cluded efficiency studies of <strong>the</strong> UK build<strong>in</strong>g societies sector <strong>in</strong> <strong>the</strong> literature review because<br />
of <strong>the</strong> build<strong>in</strong>g societies’ mutual characteristics, which are common to o<strong>the</strong>r (although not all) European<br />
sav<strong>in</strong>gs banks. The UK build<strong>in</strong>g societies, however, are not <strong>in</strong>cluded <strong>in</strong> <strong>the</strong> estimations conta<strong>in</strong>ed <strong>in</strong><br />
section 4 of this paper, because <strong>the</strong>y are not legally def<strong>in</strong>ed as sav<strong>in</strong>gs banks and <strong>the</strong>ir activities are<br />
6
decomposed <strong>in</strong>to changes <strong>in</strong> pure technical efficiency, changes <strong>in</strong> scale efficiency and<br />
changes <strong>in</strong> <strong>in</strong>put congestion. Glass and McKillop (1999) found evidence of substantial<br />
productivity growth be<strong>in</strong>g caused <strong>in</strong> <strong>the</strong> ma<strong>in</strong> by progressive shifts <strong>in</strong> technology.<br />
Although improvements <strong>in</strong> efficiency were found, <strong>the</strong>se changes were small and due to<br />
improvements <strong>in</strong> scale efficiency. A third major f<strong>in</strong>d<strong>in</strong>g was that <strong>the</strong>re has been a large<br />
<strong>in</strong>crease <strong>in</strong> <strong>the</strong> atta<strong>in</strong>ment of size efficiency. The technical efficiency estimates of Glass<br />
and McKillop confirmed <strong>the</strong> earlier f<strong>in</strong>d<strong>in</strong>gs of Drake and Weyman-Jones.<br />
The above literature review draws attention to <strong>the</strong> limited number of crosscountry<br />
efficiency studies. It also highlights <strong>the</strong> ma<strong>in</strong> techniques, both parametric and<br />
non-parametric, used to model <strong>the</strong>se relationships. While <strong>the</strong> debate cont<strong>in</strong>ues as to <strong>the</strong><br />
most appropriate methodology, <strong>the</strong>re appears to be a preference <strong>in</strong> recent US studies for<br />
<strong>the</strong> parametric approach, (for example see Kaparakis et al. (1994), Mester (1996),<br />
Mitchell and Onvural (1996) and Mester and Berger (1997)). Resti (1997), <strong>in</strong> his study<br />
of <strong>the</strong> Italian bank<strong>in</strong>g market, has also shown that both l<strong>in</strong>ear programm<strong>in</strong>g and<br />
stochastic cost frontier approaches tend to provide similar cost efficiency results. (A<br />
f<strong>in</strong>d<strong>in</strong>g also confirmed by Drake and Weyman-Jones, 1996.) This study, <strong>the</strong>refore, aims<br />
to use a parametric approach - <strong>the</strong> stochastic cost frontier and Fourier Flexible (FF)<br />
functional form - to approximate <strong>the</strong> underly<strong>in</strong>g cost characteristics of <strong>the</strong> European<br />
sav<strong>in</strong>gs bank <strong>in</strong>dustry <strong>from</strong> which estimates of X-efficiency and scale economies will be<br />
obta<strong>in</strong>ed.<br />
heavily dependent on mortgage f<strong>in</strong>ance, whereas o<strong>the</strong>r European sav<strong>in</strong>gs banks are more diversified <strong>in</strong><br />
terms of <strong>the</strong>ir assets.<br />
7
3. Methodology<br />
While <strong>the</strong>re cont<strong>in</strong>ues to be debate about <strong>the</strong> def<strong>in</strong>ition of outputs used <strong>in</strong> cost<br />
efficiency studies, we follow (like many o<strong>the</strong>r empirical researchers) along <strong>the</strong> l<strong>in</strong>es of <strong>the</strong><br />
traditional <strong>in</strong>termediation approach as suggested by Sealey and L<strong>in</strong>dley (1977), where <strong>the</strong><br />
<strong>in</strong>puts, labour, physical capital and deposits are used to produce earn<strong>in</strong>g assets. Two of<br />
our outputs, total loans and total securities are earn<strong>in</strong>g assets and we also <strong>in</strong>clude total<br />
off-balance sheet items (measured <strong>in</strong> nom<strong>in</strong>al terms) as a third output. Although <strong>the</strong><br />
latter are technically not earn<strong>in</strong>g assets, this type of bus<strong>in</strong>ess constitutes an <strong>in</strong>creas<strong>in</strong>g<br />
source of <strong>in</strong>come for banks and <strong>the</strong>refore should be <strong>in</strong>cluded when model<strong>in</strong>g banks' cost<br />
characteristics, o<strong>the</strong>rwise, total output would tend to be understated (Jagtiani and<br />
Khanthavit, 1996) 7 .<br />
Inefficiency measures are estimated us<strong>in</strong>g <strong>the</strong> stochastic cost frontier approach.<br />
This approach labels a bank as <strong>in</strong>efficient if its costs are higher than those predicted for<br />
an efficient bank produc<strong>in</strong>g <strong>the</strong> same <strong>in</strong>put/output comb<strong>in</strong>ation and <strong>the</strong> difference<br />
cannot be expla<strong>in</strong>ed by statistical noise. The cost frontier is obta<strong>in</strong>ed by estimat<strong>in</strong>g a<br />
cost function with a composite error term, <strong>the</strong> sum of a two-sided error represent<strong>in</strong>g<br />
random fluctuations <strong>in</strong> cost and a one-sided positive error term represent<strong>in</strong>g<br />
<strong>in</strong>efficiency.<br />
Ferrier and Lovell (1990) have shown that <strong>in</strong>efficiency measures for <strong>in</strong>dividual<br />
firms can be estimated us<strong>in</strong>g <strong>the</strong> stochastic frontier approach as <strong>in</strong>troduced by Aigner et al.<br />
7 Mester (1996) has suggested that risk should be controlled for <strong>in</strong> <strong>the</strong> cost function, but because<br />
standardised data on such items as loan-loss provisions and BIS capital ratios were unavailable for many<br />
banks <strong>in</strong> <strong>the</strong> sample, <strong>the</strong> authors could not <strong>in</strong>clude risk terms <strong>in</strong> <strong>the</strong> cost function specification.<br />
8
(1977) and Meeusen and van den Broeck (1977). The s<strong>in</strong>gle-equation stochastic cost<br />
function model can be given as:<br />
TC = TC(Q<br />
i<br />
, P i ) + ε i<br />
(1)<br />
where TC is observed total cost, Q i is a vector of outputs, and P i is an <strong>in</strong>put-price vector.<br />
Follow<strong>in</strong>g Aigner et al. (1977), we assume that <strong>the</strong> error of <strong>the</strong> cost function is:<br />
ε = u + v (2)<br />
where u and v are <strong>in</strong>dependently distributed; u is assumed to be distributed as half-normal,<br />
2<br />
~ N( 0,<br />
u<br />
)<br />
u σ , that is, a positive disturbance captur<strong>in</strong>g <strong>the</strong> effects of <strong>in</strong>efficiency, and v is<br />
assumed to be distributed as two-sided normal with zero mean and variance, σ 2 v, captur<strong>in</strong>g<br />
<strong>the</strong> effects of <strong>the</strong> statistical noise.<br />
Observation-specific estimates of <strong>the</strong> <strong>in</strong>efficiencies, u, can be estimated by us<strong>in</strong>g<br />
<strong>the</strong> conditional mean of <strong>the</strong> <strong>in</strong>efficiency term, given <strong>the</strong> composed error term, as proposed<br />
by Jondrow et al. (1982). The mean of this conditional distribution for <strong>the</strong> half-normal<br />
model is shown as:<br />
σλ ⎡ f( εi<br />
λ / σ )<br />
E(u | ) = 1+ 1- F( / ) +<br />
i εi 2 ⎢<br />
λ ⎣ εi<br />
λ σ<br />
⎛<br />
⎜<br />
⎝<br />
εi<br />
λ<br />
σ<br />
⎞ ⎤<br />
⎟<br />
⎠ ⎥<br />
⎦<br />
(3)<br />
where λ = σ u /σ v and total variance, σ 2 = σ 2 u + σ 2 v; F(.) and f(.) are <strong>the</strong> standard normal<br />
distribution and density functions, respectively. E(u⏐ε) is an unbiased but <strong>in</strong>consistent<br />
estimator of u i , s<strong>in</strong>ce regardless of N, <strong>the</strong> variance of <strong>the</strong> estimator rema<strong>in</strong>s non-zero (see<br />
Greene, 1993; pp.80-82). Jondrow et al. (1982) have shown that <strong>the</strong> ratio of <strong>the</strong> variability<br />
for u and v can be used to measure a banks' relative <strong>in</strong>efficiency, where λ = σ u /σ v , is a<br />
9
measure of <strong>the</strong> amount of variation stemm<strong>in</strong>g <strong>from</strong> <strong>in</strong>efficiency relative to noise for <strong>the</strong><br />
sample. The X-<strong>in</strong>efficiency term, u, is assumed to rema<strong>in</strong> constant over time for each<br />
bank. Estimates of this model can be computed by maximis<strong>in</strong>g <strong>the</strong> likelihood function<br />
directly (see Olson, Schmidt and Waldman, 1980).<br />
Previous studies modell<strong>in</strong>g <strong>in</strong>ternational bank <strong>in</strong>efficiencies such as, Allen and Rai<br />
(1996) and Vennet (1998) and those which exam<strong>in</strong>e US banks, such as Kaparakis et al.<br />
(1994), and Mester (1996), all use <strong>the</strong> half-normal specification to test for <strong>in</strong>efficiency<br />
differences between bank<strong>in</strong>g <strong>in</strong>stitutions 8 .<br />
The next step, given <strong>the</strong> choice of <strong>the</strong> half-normal <strong>in</strong>efficiency stochastic frontier<br />
approach, relates to choos<strong>in</strong>g <strong>the</strong> underly<strong>in</strong>g cost function specification. In this study, we<br />
use <strong>the</strong> Fourier Flexible (FF) form to exam<strong>in</strong>e <strong>the</strong> specification, which best fits <strong>the</strong><br />
underly<strong>in</strong>g cost structure of EU bank<strong>in</strong>g systems. Gallant (1981, 1982), Mitchell and<br />
Onvural (1996) and Berger et al. (1997) have stated that <strong>the</strong> FF is <strong>the</strong> global<br />
approximation which can be shown to dom<strong>in</strong>ate <strong>the</strong> conventional translog functional<br />
form 9 . Berger et al. (1997) report that local approximations such as <strong>the</strong> translog may<br />
8 See Bauer (1990) for a detailed review of <strong>the</strong> frontier literature and how different stochastic assumptions<br />
can be made. Cebenoyan et al. (1993), for example, uses <strong>the</strong> truncated normal model. Mester (1993) <strong>in</strong><br />
common with many studies uses <strong>the</strong> half-normal distribution. Stevenson (1980) and Greene (1990) have<br />
used <strong>the</strong> normal and gamma model, respectively. Altunba and Molyneux (1994) f<strong>in</strong>d that efficiency<br />
estimates are relatively <strong>in</strong>sensitive to different distributional assumptions when test<strong>in</strong>g <strong>the</strong> half normal,<br />
truncated normal, exponential and gamma efficiency distributions, as all distributions yield similar<br />
<strong>in</strong>efficiency levels for <strong>the</strong> German bank<strong>in</strong>g market. Vennet (1998) uses both <strong>the</strong> half-normal and<br />
exponential distributions to derive <strong>the</strong> efficiencies, but notes that <strong>the</strong>re was little difference between <strong>the</strong><br />
two and so reports <strong>the</strong> half-normal estimates.<br />
9 The translog functional form for a cost function represents a second-order Taylor series approximation of<br />
any arbitrary, twice-differentiable cost function at a given (local) po<strong>in</strong>t. This restrictive property of <strong>the</strong><br />
translog forms part of White’s (1980) critique, which led Gallant (1981) to propose <strong>the</strong> Fourier flexible<br />
functional form. Ivaldi et al. (1996) argue that a second-order approximation is <strong>in</strong>sufficient and at least a<br />
third-order approximation is required to generate a flexible cost function. The translog, however, is nested <strong>in</strong><br />
a third-order approximation for <strong>the</strong> Fourier. Gallant (1981) highlights White’s criticism of <strong>the</strong> translog when<br />
he states that Taylor’s <strong>the</strong>orem leads to misunderstand<strong>in</strong>g of parameter estimates and test statistics. This is<br />
because statistical methods ‘essentially expand <strong>the</strong> true function <strong>in</strong> a (general) Fourier series – not <strong>in</strong> a<br />
Taylor’s series’ (Gallant, 1981, p. 212). Ivaldi et al. (1996) state that fix<strong>in</strong>g <strong>the</strong> order of approximation <strong>in</strong> <strong>the</strong><br />
expansion allows <strong>the</strong> estimation of <strong>the</strong> Fourier flexible form via parametric estimation methods.<br />
10
distort scale economy measurements s<strong>in</strong>ce it imposes a symmetric U-shaped average cost<br />
curve. This feature of <strong>the</strong> translog might not fit very well data that are far <strong>from</strong> <strong>the</strong> mean<br />
<strong>in</strong> terms of output size or mix (Berger and Mester, 1997). The FF alleviates this problem<br />
s<strong>in</strong>ce it can approximate any cont<strong>in</strong>uous function and any of its derivatives (up to a fixed<br />
order). Any <strong>in</strong>ferences that are drawn <strong>from</strong> estimates of <strong>the</strong> FF are unaffected by<br />
specification errors (Ivaldi et al., 1996). S<strong>in</strong>ce <strong>the</strong> FF is a comb<strong>in</strong>ation of polynomial and<br />
trigonometric expansions, <strong>the</strong> order of approximation can <strong>in</strong>crease with <strong>the</strong> size of <strong>the</strong><br />
sample size. This is due to <strong>the</strong> ma<strong>the</strong>matical behaviour of <strong>the</strong> s<strong>in</strong>e and cos<strong>in</strong>e functions<br />
which are mutually orthogonal over <strong>the</strong> [0, 2π] <strong>in</strong>terval and function space-spann<strong>in</strong>g.<br />
Berger and Mester (1997) note that goodness of fit for <strong>the</strong> estimated efficient frontier is<br />
important <strong>in</strong> estimat<strong>in</strong>g efficiency, s<strong>in</strong>ce <strong>in</strong>efficiencies are measured as deviations <strong>from</strong> <strong>the</strong><br />
frontier. The global property is important <strong>in</strong> bank<strong>in</strong>g where scale, product mix and o<strong>the</strong>r<br />
<strong>in</strong>efficiencies are often heterogeneous, <strong>the</strong>refore, local approximations (such as those<br />
generated by <strong>the</strong> translog) may be relatively poor approximation to <strong>the</strong> underly<strong>in</strong>g true cost<br />
function.<br />
Ivaldi et al. (1996) state <strong>the</strong> Fourier can represent a broader range of cost structures<br />
than o<strong>the</strong>r functional forms. Those authors determ<strong>in</strong>e differences <strong>in</strong> <strong>the</strong> description of a<br />
technology by fitt<strong>in</strong>g Fourier and translog cost functions. They concur that <strong>the</strong> Fourier is<br />
suitable for estimat<strong>in</strong>g cost functions on panel data sets that are characterised by variables<br />
with large variances. For this reason, <strong>the</strong> local po<strong>in</strong>t estimate produced by <strong>the</strong> translog<br />
functional form is <strong>in</strong>appropriate to approximate <strong>the</strong> true technology. The results of <strong>the</strong><br />
tests performed by Ivaldi et al. (1996) f<strong>in</strong>d <strong>the</strong> global approximation of <strong>the</strong> Fourier better<br />
captures <strong>the</strong> heterogeneity of <strong>the</strong>ir sample, whilst <strong>the</strong> translog only revealed average<br />
properties.<br />
11
Hence, <strong>the</strong> FF is a semi-nonparametric approach used to tackle <strong>the</strong> problem aris<strong>in</strong>g<br />
when <strong>the</strong> true functional form of <strong>the</strong> relationship is unknown. As noted above, <strong>the</strong><br />
methodology was first proposed by Gallant (1981, 1982), and later discussed by Elbadawi,<br />
Gallant and Souza (1983), Chalfant and Gallant (1985), Eastwood and Gallant (1991),<br />
Gallant and Souza (1991). It has been applied to <strong>the</strong> analysis of bank cost efficiency by<br />
Spong et al. (1995), Mitchell and Onvural (1996) and Berger et al. (1997). Vennet (1998)<br />
estimates both <strong>the</strong> translog and FF cost function <strong>in</strong> his study of European universal and<br />
specialist banks but reports only <strong>the</strong> translog estimates because <strong>the</strong> results are similar.<br />
To calculate <strong>the</strong> <strong>in</strong>efficiency measures, <strong>the</strong> FF form, <strong>in</strong>clud<strong>in</strong>g a standard translog<br />
and all first, second and third-order trigonometric terms, as well as a two-component error<br />
structure is estimated us<strong>in</strong>g a maximum likelihood procedure. This is shown as:<br />
3<br />
∑[<br />
a<br />
i= 1<br />
i<br />
∑<br />
1 ⎡<br />
⎢<br />
2 ⎣<br />
cos (<br />
3<br />
i= 1<br />
3<br />
∑<br />
j= 1<br />
3<br />
∑<br />
i= 1<br />
3<br />
∑<br />
i= 1<br />
z<br />
) +<br />
i<br />
ln<br />
3<br />
∑<br />
j= 1<br />
3<br />
∑<br />
m= 1<br />
b<br />
δ<br />
ρ<br />
3<br />
∑[<br />
a<br />
k≥<br />
j,<br />
k≠i<br />
s<strong>in</strong> (<br />
i<br />
TC<br />
ij<br />
= α0+<br />
im<br />
lnQ<br />
lnQ<br />
z<br />
ijk<br />
i<br />
)<br />
i<br />
3<br />
∑<br />
lnQ +<br />
i<br />
3<br />
] +∑<br />
cos (<br />
i= 1<br />
i= 1<br />
z<br />
αilnQ+<br />
j<br />
lnPm+<br />
i<br />
+<br />
3<br />
∑<br />
l= 1<br />
3<br />
∑<br />
i= 1<br />
∑<br />
3<br />
∑[<br />
a<br />
j=<br />
1<br />
z<br />
j<br />
+<br />
i<br />
∑<br />
3<br />
3<br />
l= 1<br />
m= 1<br />
γ<br />
β<br />
ψ T lnQ +<br />
z<br />
i<br />
k<br />
ij<br />
) +<br />
lm<br />
l<br />
cos (<br />
b<br />
lnPl+<br />
t1T<br />
+<br />
lnP<br />
i<br />
ijk<br />
z<br />
l<br />
∑<br />
+<br />
s<strong>in</strong> (<br />
lnP<br />
3<br />
l= 1<br />
i<br />
θ lT<br />
lnP l+<br />
z<br />
z<br />
i<br />
) +<br />
j<br />
m<br />
+<br />
+ t11T<br />
z<br />
b<br />
j<br />
ij<br />
+<br />
2<br />
⎤<br />
⎥+<br />
⎦<br />
s<strong>in</strong> (<br />
z<br />
k<br />
)<br />
z<br />
i<br />
+<br />
] +<br />
(4)<br />
where<br />
lnTC = <strong>the</strong> natural logarithm of total costs (Operat<strong>in</strong>g and F<strong>in</strong>ancial cost);<br />
lnQ i = <strong>the</strong> natural logarithm of bank outputs (i.e. loans, securities, off-balance sheet<br />
items);<br />
ε<br />
z<br />
j<br />
)<br />
] +<br />
12
lnP l = <strong>the</strong> natural logarithm of ith <strong>in</strong>put prices (i.e. wage rate, <strong>in</strong>terest rate and physical<br />
capital price);<br />
T = time trend;<br />
Z i = <strong>the</strong> adjusted values of <strong>the</strong> log output lnQ i such that <strong>the</strong>y span <strong>the</strong> <strong>in</strong>terval [0, 2π];<br />
α, β, δ i , γ, Ψ, θ, ρ, a, b and t are coefficients to be estimated.<br />
Follow<strong>in</strong>g Berger et al. (1997), <strong>the</strong> study applies Fourier terms only for <strong>the</strong><br />
outputs, leav<strong>in</strong>g <strong>the</strong> <strong>in</strong>put price effects to be def<strong>in</strong>ed entirely by <strong>the</strong> translog terms. The<br />
primary aim is to ma<strong>in</strong>ta<strong>in</strong> <strong>the</strong> limited number of Fourier terms for describ<strong>in</strong>g <strong>the</strong> scale<br />
and <strong>in</strong>efficiency measures associated with differences <strong>in</strong> bank size. Moreover, <strong>the</strong> usual<br />
<strong>in</strong>put price homogeneity restrictions can be imposed on logarithmic price terms, whereas<br />
<strong>the</strong>y cannot be easily imposed on <strong>the</strong> trigonometric terms 10 .<br />
In addition, <strong>the</strong> scaled log-output quantities, z i , are calculated as z i = µ i (lnQ i +<br />
w i ), lnQ i are unscaled log-output quantities; µ i and w i are scaled factors, writ<strong>in</strong>g <strong>the</strong><br />
periodic s<strong>in</strong>e and cos<strong>in</strong>e trigonometric functions with<strong>in</strong> one period of length 2π before<br />
apply<strong>in</strong>g <strong>the</strong> FF methodology (see Gallant 1981). The µ i s are chosen to make <strong>the</strong> largest<br />
observations for each scaled log-output variable close to 2π; w i s are restricted to assume<br />
<strong>the</strong> smallest values close to zero. In this study, we restricted <strong>the</strong> z i to span between 0.001<br />
10 Mitchell and Onvural (1996; p.181) did not impose restrictions on <strong>the</strong> trigonometric <strong>in</strong>put price<br />
coefficients for computational reasons. Gallant (1982), however, has shown that this should not prevent<br />
an estimated FF cost equation <strong>from</strong> closely approximat<strong>in</strong>g <strong>the</strong> true cost function.<br />
13
and 6 to reduce approximation problems near <strong>the</strong> endpo<strong>in</strong>ts as discussed by Gallant<br />
(1981) and applied by Mitchell and Onvural (1996) 11 .<br />
S<strong>in</strong>ce <strong>the</strong> duality <strong>the</strong>orem requires that <strong>the</strong> cost function is l<strong>in</strong>early homogeneous<br />
<strong>in</strong> <strong>in</strong>put prices and cont<strong>in</strong>uity requires that <strong>the</strong> second order parameters are symmetric, <strong>the</strong><br />
follow<strong>in</strong>g restrictions apply to <strong>the</strong> parameters of <strong>the</strong> cost function <strong>in</strong> equation (4):<br />
3<br />
∑<br />
l= 1<br />
β<br />
l<br />
=<br />
1;<br />
3<br />
∑<br />
l= 1<br />
δ<br />
γ<br />
ij<br />
lm<br />
=<br />
= 0<br />
δ<br />
ji<br />
;<br />
3<br />
∑<br />
l= 1<br />
θ<br />
and γ<br />
l<br />
lm<br />
= 0 ;<br />
= γ<br />
ml<br />
3<br />
∑<br />
m = 1<br />
ρ<br />
im<br />
=<br />
0;<br />
(5)<br />
The cost frontiers are estimated us<strong>in</strong>g <strong>the</strong> random effects panel data approach (as<br />
<strong>in</strong> Lang and Welzel, 1996). We use <strong>the</strong> panel data approach because technical efficiency<br />
is better studied and modelled with panels (see Baltagi and Griff<strong>in</strong>, 1988; Cornwell,<br />
Schmidt and Sickles, 1990; Kumbhakar, 1993). The random effects model is preferred<br />
over <strong>the</strong> fixed effects model because fixed effects is considered to be <strong>the</strong> more<br />
appropriate specification if we are focus<strong>in</strong>g on a specific set of N firms. Moreover, and<br />
if N is large, a fixed effects model would also lead to a substantial loss of degrees of<br />
freedom (see, for example, Baltagi, 1995). Thus, <strong>the</strong> unbalanced nature of our dataset<br />
determ<strong>in</strong>es <strong>the</strong> use of <strong>the</strong> random effects model.<br />
11 Berger et al. (1997) restricted z i to span [.1; 2, .9; 2], however, <strong>the</strong> use of this <strong>in</strong>terval provided<br />
<strong>in</strong>consistent results <strong>in</strong> <strong>the</strong> present study. While Mitchell and Onvural (1996) adopted a second<br />
trigonometric order <strong>in</strong> <strong>the</strong>ir study, we preferred to use a third trigonometric order follow<strong>in</strong>g Berger et al.<br />
(1997). Accord<strong>in</strong>g to Gallant (1982), <strong>in</strong>creas<strong>in</strong>g <strong>the</strong> number of trigonometric orders, relative to sample<br />
size, reduces approximation errors. Eastwood and Gallant (1991) show that <strong>the</strong> FF cost function produces<br />
consistent and asymptotically normal parameter estimates when <strong>the</strong> number of parameters estimated is set<br />
to <strong>the</strong> number of effective observations raised to <strong>the</strong> two thirds power. However, Gallant (1981) advocates<br />
that even a limited number of trigonometric orders is sufficient to obta<strong>in</strong> global approximations. The<br />
choice of <strong>the</strong> range used by different researchers is, however, subjective and relative to <strong>the</strong> size of data set<br />
analysed.<br />
14
With<strong>in</strong> sample scale economies are calculated as <strong>in</strong> Mester (1996) and are<br />
evaluated at <strong>the</strong> mean output and <strong>in</strong>put price levels for <strong>the</strong> respective size quartiles. A<br />
measure of economies of scale (SE) is given by <strong>the</strong> follow<strong>in</strong>g cost elasticity by<br />
differentiat<strong>in</strong>g <strong>the</strong> cost function <strong>in</strong> equation (4) with respect to output. This gives us:<br />
3<br />
3<br />
3 3<br />
3 3<br />
3<br />
SE = = i+ ij Q j<br />
∑ ∑α<br />
∑∑δ<br />
ln + ∑∑ ρ im<br />
ln Pm+<br />
∑<br />
i=1 ∂ ln Qi<br />
i=1 i=1 j=1<br />
i=1 m=1<br />
i=1<br />
3<br />
∑<br />
i=<br />
1<br />
[ ]<br />
3 3<br />
[ a s<strong>in</strong>( Z ) − b cos( Z )] + a s<strong>in</strong>( Z + Z ) − b cos( Z + Z )<br />
i<br />
3<br />
∑<br />
i=<br />
1<br />
∂ lnTC<br />
i<br />
3<br />
∑<br />
j=<br />
1<br />
i<br />
3<br />
∑<br />
k≥<br />
j,<br />
k ≠i<br />
[ a s<strong>in</strong>( Z + Z + Z ) − b cos( Z + Z + Z )]<br />
ijk<br />
i<br />
∑<br />
i=<br />
1<br />
i<br />
∑<br />
j=<br />
1<br />
j<br />
ij<br />
k<br />
i<br />
ijk<br />
j<br />
i<br />
ij<br />
j<br />
i<br />
k<br />
ψ T +<br />
i<br />
j<br />
+<br />
(6)<br />
If SE < 1 <strong>the</strong>n <strong>in</strong>creas<strong>in</strong>g returns to scale, imply<strong>in</strong>g economies of scale;<br />
If SE = 1 <strong>the</strong>n constant returns to scale;<br />
If SE > 1 <strong>the</strong>n decreas<strong>in</strong>g returns to scale, imply<strong>in</strong>g diseconomies of scale.<br />
4. Data and Results<br />
This study uses banks' balance sheet and <strong>in</strong>come statement data for a sample of<br />
European sav<strong>in</strong>gs banks between 1989 and 1996, obta<strong>in</strong>ed <strong>from</strong> <strong>the</strong> London-based<br />
International Bank Credit Analysis Ltd's 'BankScope' database. Table 1 reports <strong>the</strong><br />
def<strong>in</strong>ition, mean and standard deviation of <strong>the</strong> <strong>in</strong>put and output variables <strong>in</strong> real terms<br />
used <strong>in</strong> <strong>the</strong> cost frontier estimations, all data are <strong>in</strong> real 1996 terms and <strong>the</strong>y have been<br />
converted us<strong>in</strong>g <strong>in</strong>dividual country GDP deflators. (Parameter estimates of <strong>the</strong> cost<br />
frontier are shown <strong>in</strong> Table A1 <strong>in</strong> <strong>the</strong> Appendix.)<br />
Table 1 here.<br />
15
Table 2 shows <strong>the</strong> composition of <strong>the</strong> European sav<strong>in</strong>gs banks sample. It should<br />
be noted that a small number of sav<strong>in</strong>gs banks are represented <strong>in</strong> F<strong>in</strong>land, Luxembourg,<br />
<strong>the</strong> Ne<strong>the</strong>rlands, Portugal and Sweden. This is due partly to <strong>the</strong> fact that <strong>the</strong>re are a<br />
number of very small sav<strong>in</strong>gs banks <strong>in</strong> F<strong>in</strong>land and Sweden for which data are difficult<br />
to obta<strong>in</strong>, and because <strong>the</strong> sav<strong>in</strong>gs bank sectors <strong>in</strong> Luxembourg, <strong>the</strong> Ne<strong>the</strong>rlands, and<br />
Portugal are dom<strong>in</strong>ated by a relatively large s<strong>in</strong>gle sav<strong>in</strong>gs bank. In contrast, <strong>the</strong> German<br />
sav<strong>in</strong>gs banks sector is most heavily represented followed by Italy, Spa<strong>in</strong>, Denmark,<br />
Austria and Belgium. The large number of German sav<strong>in</strong>gs banks <strong>from</strong> 1993 onwards<br />
are due to limited data availability prior to that date. The table also shows that <strong>the</strong> most<br />
comprehensive data were available for 1994-1996 and that sav<strong>in</strong>gs banks with assets<br />
size rang<strong>in</strong>g between ECU 500 million and ECU 2,500 million accounted for over half<br />
<strong>the</strong> sample.<br />
Table 2 here.<br />
Tables 3 and 4 show <strong>the</strong> scale economy estimates and mean <strong>in</strong>efficiencies of<br />
national sav<strong>in</strong>gs banks sectors for different sizes of banks over <strong>the</strong> years 1989 to 1996.<br />
Generally, scale economies are prevalent across <strong>the</strong> sector and typically vary between 7<br />
and 10 percent. Thus, a 100 percent <strong>in</strong>crease <strong>in</strong> <strong>the</strong> level of all outputs would lead to<br />
about a 93 to 90 percent <strong>in</strong>crease <strong>in</strong> total costs, respectively. The bottom part of Table 3<br />
shows that larger sav<strong>in</strong>gs banks, across all European countries, realise greater scale<br />
economies compared with <strong>the</strong>ir smaller counterparts. Overall, banks under ECU 200<br />
million <strong>in</strong> assets experience constant returns to scale, <strong>the</strong>reafter, economies <strong>in</strong>crease<br />
systematically with size. In o<strong>the</strong>r words, scale economies become larger with size and<br />
16
optimal bank size appears to be <strong>in</strong>exhausted 12 . The magnitude of <strong>the</strong>se scale economy<br />
estimates accord with <strong>the</strong> f<strong>in</strong>d<strong>in</strong>gs of previous studies of <strong>the</strong> US bank<strong>in</strong>g market (for<br />
example, see Berger et al. 1993), although only a handful of studies f<strong>in</strong>d evidence of<br />
<strong>in</strong>exhaustable scale economies (see, for example, McAllister and McManus, 1993;<br />
Hughes et al., 1995; and Lang and Welzel, 1996).<br />
Table 3 here.<br />
Mean <strong>in</strong>efficiencies are shown <strong>in</strong> Table 4 by national sav<strong>in</strong>gs banks sectors. The<br />
general f<strong>in</strong>d<strong>in</strong>g is that <strong>in</strong>dustry <strong>in</strong>efficiency rose between 1989 and 1991 (<strong>from</strong> 22.3% to<br />
22.7%), <strong>the</strong>reafter fall<strong>in</strong>g to a level of 21.6% <strong>in</strong> 1996. This suggests that <strong>the</strong> same level<br />
of output could be produced with approximately 78% of current <strong>in</strong>puts if sav<strong>in</strong>gs banks<br />
were operat<strong>in</strong>g on <strong>the</strong> efficient frontier. This is <strong>in</strong> <strong>the</strong> same range as those found <strong>in</strong> <strong>the</strong><br />
US literature as well as <strong>the</strong> studies undertaken by Resti (1997) on Italian banks and<br />
Grifell-Tatje and Lovell (1996) on Spanish sav<strong>in</strong>gs banks.<br />
Table 4 here.<br />
The lower panel of Table 4 shows <strong>the</strong> distribution of mean X-<strong>in</strong>efficiencies by<br />
bank asset size. As noted above, smaller sav<strong>in</strong>gs banks are found to be more cost X-<br />
efficient than larger sav<strong>in</strong>gs banks. Sav<strong>in</strong>gs banks with assets less than ECU 99.9<br />
million and between ECU 100-199.9 million, have mean X-<strong>in</strong>efficiency of 20.8% and<br />
21.2%, respectively, compared with larger sav<strong>in</strong>gs banks, with assets between ECU<br />
2,500-4999.9 and greater than ECU 5,000 million, and mean X-<strong>in</strong>efficiencies of 22.2%<br />
and 22.1%, respectively. Yet, <strong>the</strong> two smallest classes of sav<strong>in</strong>gs banks realise<br />
12 Our f<strong>in</strong>d<strong>in</strong>g of <strong>in</strong>exhausted optimal bank size might be due to <strong>the</strong> relatively small size of most sav<strong>in</strong>gs<br />
banks. Similar f<strong>in</strong>d<strong>in</strong>gs appear elsewhere <strong>in</strong> <strong>the</strong> bank<strong>in</strong>g literature, for example, Lang and Welzel (1996),<br />
who <strong>in</strong> a study of German co-operative banks, attribute a f<strong>in</strong>d<strong>in</strong>g of scale economies <strong>in</strong> all size classes to<br />
<strong>the</strong> relatively small size of banks <strong>in</strong> <strong>the</strong>ir sample.<br />
17
diseconomies of scale <strong>in</strong> all countries (except Austria and Italy). This f<strong>in</strong>d<strong>in</strong>g suggests<br />
<strong>the</strong>re are unrealised benefits that could be achieved through <strong>in</strong>creased size for small<br />
sav<strong>in</strong>gs banks, or through consolidation. The fact that scale economies <strong>in</strong>crease with<br />
size and that optimal bank size is <strong>in</strong>exhausted supports an argument for fur<strong>the</strong>r<br />
consolidation.<br />
Consider<strong>in</strong>g that <strong>the</strong> years 1993 to 1996 conta<strong>in</strong> <strong>the</strong> most data, Table 4 shows<br />
that <strong>the</strong> smallest size group is <strong>the</strong> most mean cost X-efficient between 1993 and 1996,<br />
despite mean X-<strong>in</strong>efficiency deteriorat<strong>in</strong>g over this period. At 1996, however, <strong>the</strong> most<br />
cost-efficient sav<strong>in</strong>gs banks had assets between ECU 200-299.9 million, followed by<br />
size classes ECU 100-199.9 (21.3%), ECU 1-99.9 million (21.4%) and ECU 1,000–<br />
2,499.9 million (21.5%). The least X-efficient size class <strong>in</strong> 1996 was <strong>the</strong> largest class<br />
(above ECU 5,000 million) with a mean X-<strong>in</strong>efficiency of 22%. The data for 1996,<br />
however, show first, that smaller sav<strong>in</strong>gs banks are los<strong>in</strong>g <strong>the</strong>ir apparent cost efficiency<br />
advantage, second, slightly larger sav<strong>in</strong>gs banks are becom<strong>in</strong>g more X-efficient (ECU<br />
200-299.9 million), which could reflect policy makers earlier decision to create sav<strong>in</strong>gs<br />
banks of greater mass. F<strong>in</strong>ally, <strong>the</strong> range of X-<strong>in</strong>efficiencies across sav<strong>in</strong>gs banks of<br />
different size class has narrowed suggest<strong>in</strong>g that previously visible cost efficiency<br />
advantages perta<strong>in</strong><strong>in</strong>g to asset size may be dissipat<strong>in</strong>g over time (see Table 4).<br />
There are four organisational and economic models that are commonly be<strong>in</strong>g<br />
followed by European sav<strong>in</strong>gs banks 13 . These models are not entirely heterogeneous<br />
with several common elements, <strong>in</strong>clud<strong>in</strong>g commitment to social and economic activities<br />
with<strong>in</strong> localities and <strong>the</strong> shar<strong>in</strong>g of technology. Generally, <strong>the</strong> models reflect a spectrum<br />
of different ownership types, rang<strong>in</strong>g <strong>from</strong> state to private ownership and non-profit<br />
18
orientation to profit. The first model is <strong>the</strong> ‘state’ model <strong>in</strong> which sav<strong>in</strong>gs banks,<br />
generally, are non-profit <strong>in</strong>stitutions owned by mutual authorities and subject to some<br />
operational and geographic boundaries (for example, Germany). The second ‘mixed’<br />
model has a more diverse ownership structure than <strong>the</strong> ‘state’ model, <strong>in</strong>clud<strong>in</strong>g<br />
municipal authorities, depositors and employees (for example, Spa<strong>in</strong>). Under <strong>the</strong> ‘state’<br />
and ‘mixed’ models sav<strong>in</strong>gs banks have limited means of rais<strong>in</strong>g equity capital due to<br />
<strong>the</strong>ir ownership. This is not <strong>the</strong> case <strong>in</strong> <strong>the</strong> two rema<strong>in</strong><strong>in</strong>g models, <strong>the</strong> ‘<strong>in</strong>-transition’<br />
model and <strong>the</strong> ‘marketised model’ (for example, Italy and <strong>the</strong> UK, respectively). In <strong>the</strong><br />
former model, sav<strong>in</strong>gs banks are <strong>in</strong> <strong>the</strong> process of convert<strong>in</strong>g <strong>the</strong>ir organisational form<br />
to jo<strong>in</strong>t stock company status, first to reduce public fiscal responsibility to sav<strong>in</strong>gs<br />
banks, and second to allow sav<strong>in</strong>gs banks to raise private equity capital through <strong>the</strong><br />
issue of shares. The latter ‘marketised’ model is <strong>the</strong> f<strong>in</strong>al outcome of <strong>the</strong> ‘<strong>in</strong>-transition’<br />
model. It is characterised by <strong>the</strong> demutualisation of a large proportion of <strong>the</strong> sav<strong>in</strong>gs<br />
banks sector with <strong>in</strong>creas<strong>in</strong>g competitive pressures on rema<strong>in</strong><strong>in</strong>g mutuals.<br />
There is no strong evidence to suggest that one model dom<strong>in</strong>ates <strong>the</strong> o<strong>the</strong>rs <strong>in</strong><br />
terms of ei<strong>the</strong>r X-efficiency or economies of scale. In cases where <strong>the</strong> average size 14 of<br />
sav<strong>in</strong>gs banks has <strong>in</strong>creased (for example, as a result of restructur<strong>in</strong>g <strong>in</strong> France and<br />
through consolidation <strong>in</strong> Spa<strong>in</strong>), evidence that larger average size conveys translates <strong>in</strong>to<br />
greater X-efficiencies is ambiguous. Interest<strong>in</strong>gly, <strong>the</strong> least X-efficient sav<strong>in</strong>gs banks<br />
are <strong>in</strong> sectors that can be classified as ‘<strong>in</strong>-transition’ and ‘marketised’ (for example, <strong>the</strong><br />
restructured F<strong>in</strong>nish and demutualised Belgian sectors, respectively). Never<strong>the</strong>less, this<br />
13 See Gardener et al. (1997).<br />
14 The average assets size of sav<strong>in</strong>gs banks as classified by <strong>the</strong> five models is as follows. French, ECU<br />
5,699 m; German, ECU 1,427 m; Italian, ECU 3,779 m; Spanish, ECU 5,372 m; UK build<strong>in</strong>g societies,<br />
ECU 2,486 m. The data are at 1997 (Gardener et al. 1999).<br />
19
f<strong>in</strong>d<strong>in</strong>g should be treated with caution s<strong>in</strong>ce <strong>the</strong> relative importance of sav<strong>in</strong>gs banks is<br />
much reduced <strong>in</strong> such countries, and <strong>the</strong> future prospects for <strong>the</strong> rema<strong>in</strong><strong>in</strong>g sav<strong>in</strong>gs<br />
banks are unclear.<br />
Overall, <strong>the</strong> results suggest that for <strong>the</strong> sector as a whole, that greater cost<br />
sav<strong>in</strong>gs are to be obta<strong>in</strong>ed if sav<strong>in</strong>gs banks focus <strong>the</strong>ir attentions on reduc<strong>in</strong>g<br />
managerial, technological and o<strong>the</strong>r <strong>in</strong>efficiencies, compared with <strong>in</strong>creas<strong>in</strong>g size.<br />
Never<strong>the</strong>less, <strong>the</strong>re are still cost reductions of between 7 and 10 percent that can be<br />
realised through <strong>in</strong>creas<strong>in</strong>g output size.<br />
To fur<strong>the</strong>r <strong>in</strong>vestigate <strong>the</strong> determ<strong>in</strong>ants of European sav<strong>in</strong>gs banks X-<br />
<strong>in</strong>efficiency we use a logistic regression model as suggested <strong>in</strong> Mester (1993 and 1996).<br />
S<strong>in</strong>ce <strong>the</strong> values of estimated <strong>in</strong>efficiencies range between zero and one <strong>the</strong> logistic<br />
functional form is preferred over <strong>the</strong> l<strong>in</strong>ear regression model. We model <strong>the</strong> X-<br />
<strong>in</strong>efficiency values aga<strong>in</strong>st various firm-specific characteristics. The <strong>in</strong>dependent<br />
variables used <strong>in</strong>clude TASSET = bank total assets size measured <strong>in</strong> millions of ECU,<br />
CRATIO = equity/total assets, ROAA = return on average assets, NL/TASSET = net<br />
loans/total assets, OBS/TASSET = off-balance sheet items (nom<strong>in</strong>al value)/total assets<br />
and f<strong>in</strong>ally, LA/C&SF= liquid assets / customer and short-term fund<strong>in</strong>g. TASSET<br />
controls for <strong>the</strong> overall size of <strong>the</strong> bank. CRATIO is <strong>the</strong> f<strong>in</strong>ancial capital ratio and this<br />
should be <strong>in</strong>versely related to <strong>in</strong>efficiency on <strong>the</strong> grounds that banks with low<br />
<strong>in</strong>efficiency will have higher profits and hence will be able to (hold<strong>in</strong>g dividends<br />
constant) reta<strong>in</strong> more earn<strong>in</strong>gs as capital. ROAA is a performance measure and this<br />
should be <strong>in</strong>versely related to <strong>in</strong>efficiency. NL/TASSET, OBS/TASSET, and LA/C&SF<br />
are proxies for bus<strong>in</strong>ess mix. The logistic parameter estimates are shown <strong>in</strong> Table 5.<br />
Table 5 here.<br />
20
In accordance with Mester's (1996) f<strong>in</strong>d<strong>in</strong>gs, <strong>in</strong>efficiencies are <strong>in</strong>versely<br />
correlated with <strong>the</strong> f<strong>in</strong>ancial capital variable (CRATIO) and bank performance (ROAA).<br />
This is, of course, to be expected given that banks with low <strong>in</strong>efficiency will have more<br />
profits as <strong>the</strong>y will be able to (hold<strong>in</strong>g dividends constant) reta<strong>in</strong> more earn<strong>in</strong>gs as<br />
capital. The estimates also reveal that <strong>the</strong>re is an <strong>in</strong>verse relationship between asset size<br />
(TASSET) and efficiency. Efficient banks also appear to have lower loan-to-assets ratios<br />
and higher liquidity ratios. The level of sav<strong>in</strong>gs banks off-balance sheet bus<strong>in</strong>ess is not<br />
statistically related to X-efficiency.<br />
5. Conclusion<br />
This paper advances <strong>the</strong> established literature on modell<strong>in</strong>g <strong>the</strong> cost<br />
characteristics of bank<strong>in</strong>g markets by apply<strong>in</strong>g <strong>the</strong> Fourier Flexible functional form and<br />
stochastic cost frontier methodologies to estimate scale economies and X-<strong>in</strong>efficiencies<br />
for a large sample of European sav<strong>in</strong>gs banks between 1989 and 1996. As far as we are<br />
aware this is <strong>the</strong> only cross-country study that compares X-efficiencies and scale<br />
economies <strong>in</strong> <strong>the</strong> sector. The results reveal that scale economies are widespread across<br />
different countries and <strong>the</strong>y <strong>in</strong>crease with bank size. In general, scale economies are<br />
found to range between 7 and 10 percent, while X-<strong>in</strong>efficiency measures appear to be<br />
much larger, around 22 percent. These results are similar to those found <strong>in</strong> earlier US<br />
and European studies, and <strong>the</strong>y suggest that European sav<strong>in</strong>gs banks can obta<strong>in</strong> cost<br />
reductions through reduc<strong>in</strong>g managerial and o<strong>the</strong>r <strong>in</strong>efficiencies and also by <strong>in</strong>creas<strong>in</strong>g<br />
<strong>the</strong> scale of production. Overall, large sav<strong>in</strong>gs banks have scale economy advantages<br />
over <strong>the</strong>ir smaller counterparts. Size, however, does not appear to confer advantages <strong>in</strong><br />
terms of X-efficiency. Given that larger banks realise greater scale economies this may<br />
be an important factor promot<strong>in</strong>g consolidation <strong>in</strong> <strong>the</strong> European sav<strong>in</strong>gs banks <strong>in</strong>dustry.<br />
21
Several important and <strong>in</strong>terest<strong>in</strong>g f<strong>in</strong>d<strong>in</strong>gs are reported <strong>in</strong> this study. It appears<br />
that <strong>the</strong> different organisational models followed by European sav<strong>in</strong>gs banks do not<br />
convey any obvious difference <strong>in</strong> <strong>the</strong> level of X-<strong>in</strong>efficiency and economies of scale. In<br />
some sectors that are ‘<strong>in</strong>-transition’ and/or are ‘marketised’, sav<strong>in</strong>gs banks are less X-<br />
efficient than those organised under o<strong>the</strong>r models. It is unclear whe<strong>the</strong>r this relates to<br />
<strong>the</strong> authority’s dim<strong>in</strong>ish<strong>in</strong>g commitment to a viable sav<strong>in</strong>gs banks sector, or to one<br />
organisational model be<strong>in</strong>g superior to ano<strong>the</strong>r. These results, however, are important<br />
<strong>in</strong> terms of <strong>the</strong> demutualisation debate that surrounds <strong>the</strong> <strong>in</strong>dustry.<br />
Our results <strong>in</strong>dicate that smaller sav<strong>in</strong>gs banks are more X-efficient than larger<br />
banks. Whilst this f<strong>in</strong>d<strong>in</strong>g implies relative managerial quality <strong>in</strong> small sav<strong>in</strong>gs banks,<br />
we generally f<strong>in</strong>d that sav<strong>in</strong>gs banks with less than ECU 199.9 million worth of assets<br />
do not achieve economies of scale. Hence, <strong>the</strong>re is a tension between <strong>the</strong> X-efficiency<br />
and economies of scale results for small sav<strong>in</strong>gs banks with <strong>the</strong> latter f<strong>in</strong>d<strong>in</strong>g suggest<strong>in</strong>g<br />
that smaller sav<strong>in</strong>gs banks could benefit <strong>from</strong> <strong>in</strong>creased consolidation. Indeed, <strong>the</strong><br />
results <strong>in</strong>dicate that <strong>the</strong> differential <strong>in</strong> X-efficiency across different sized banks is<br />
narrow<strong>in</strong>g over time. Hence, <strong>the</strong> mean smaller sav<strong>in</strong>gs banks are becom<strong>in</strong>g less costefficient<br />
whilst <strong>the</strong> average larger sav<strong>in</strong>gs banks have become more X-efficient. There<br />
are various possible explanations for this f<strong>in</strong>d<strong>in</strong>g. A more competitive environment<br />
may exert relatively greater pressure on smaller sav<strong>in</strong>gs banks, whereas larger sav<strong>in</strong>gs<br />
banks may be able to take advantage of <strong>the</strong>ir size whilst simultaneously target<strong>in</strong>g<br />
reduc<strong>in</strong>g cost <strong>in</strong>efficiencies. Sav<strong>in</strong>gs banks participate <strong>in</strong> many shar<strong>in</strong>g arrangements,<br />
for example, <strong>in</strong> payments systems both at national and pan-European levels. It is<br />
possible that this feature of <strong>the</strong> <strong>in</strong>dustry might convey benefits <strong>in</strong> terms of economies of<br />
scale but have little or no impact on X-efficiency.<br />
22
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efficiency <strong>in</strong> giant Japanese banks’, Journal of Bank<strong>in</strong>g and F<strong>in</strong>ance, 20, 1651-<br />
1671.<br />
McKillop, D.G. and J.C. Glass (1994), ‘A cost model of build<strong>in</strong>g societies as producers of<br />
mortgages and o<strong>the</strong>r f<strong>in</strong>ancial products’, Journal of Bus<strong>in</strong>ess, F<strong>in</strong>ance and<br />
Account<strong>in</strong>g, 21(7), pp. 1031-1046.<br />
Meeusen, W. and J. van den Broeck, (1977), ‘<strong>Efficiency</strong> estimation <strong>from</strong> Cobb-Douglas<br />
production functions with composed error, International Economic Review, 18, 435-<br />
444.<br />
Mester, L.J., (1993), ‘<strong>Efficiency</strong> <strong>in</strong> <strong>the</strong> sav<strong>in</strong>gs and loan <strong>in</strong>dustry’, Journal of Bank<strong>in</strong>g and<br />
F<strong>in</strong>ance, 17, 267-286.<br />
Mester, L.J., (1996), ‘A study of bank efficiency tak<strong>in</strong>g <strong>in</strong>to account risk-preferences’,<br />
Journal of Bank<strong>in</strong>g and F<strong>in</strong>ance, 20, 1025-1045.<br />
Mitchell, K. and N.M. Onvural, (1996), ‘Economies of scale and scope at large<br />
comercial banks: <strong>Evidence</strong> <strong>from</strong> <strong>the</strong> Fourier Flexible functional form’, Journal of<br />
Money, Credit and Bank<strong>in</strong>g, Vol. 28, No. 2, 178-199.<br />
Molyneux, P., Y. Altunba and E.P.M. Gardener, (1996), <strong>Efficiency</strong> <strong>in</strong> European<br />
Bank<strong>in</strong>g, (Chichester, UK: John Wiley & Sons).<br />
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25
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techniques’, Journal of Bank<strong>in</strong>g and F<strong>in</strong>ance, Vol. 21, 221-250.<br />
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October<br />
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26
Table 1 Descriptive statistics of <strong>the</strong> outputs and <strong>in</strong>put variables used <strong>in</strong> <strong>the</strong> model,<br />
1989-1996 *<br />
Variables Description Mean StDev M<strong>in</strong> Max<br />
TC Total cost (operat<strong>in</strong>g and f<strong>in</strong>ancial cost) 138.2 437.1 0.6 9407.5<br />
(ECU m)<br />
P 1 Price of labour (%) (total personnel 0.015 0.005 0.001 0.049<br />
expenses/total assets)<br />
P 2 Price of funds (%) (total <strong>in</strong>terest 0.051 0.016 0.019 0.246<br />
expenses/total funds (demand, sav<strong>in</strong>g,<br />
time <strong>in</strong>ter-bank deposits, long-term debt,<br />
subord<strong>in</strong>ated debt and o<strong>the</strong>r))<br />
P 3 Price of physical capital (total 0.472 0.166 0.062 0.992<br />
depreciation and o<strong>the</strong>r capital<br />
expenses/total fixed assets)<br />
Q 1 The ECU value of total aggregate loans 1007.0 2648.9 3.6 45481.0<br />
(all types of loans) (ECU m)<br />
Q 2 The ECU value of total aggregate 790.2 3144.9 2.1 88368.6<br />
securities (short term <strong>in</strong>vestment, equity<br />
and o<strong>the</strong>r <strong>in</strong>vestments and public sector<br />
securities) (ECU m)<br />
Q 3 The ECU value of <strong>the</strong> off-balance sheet 261.0 3714.0 0.0 159290.0<br />
activities (nom<strong>in</strong>al values) (ECU m)<br />
Number of observations: 4,083<br />
* The figures have been deflated us<strong>in</strong>g country specific GDP deflators with 1996 as a base year.<br />
27
Table 2 European sav<strong>in</strong>gs banks sample: Number and size distribution across<br />
countries 1989-1996<br />
1989 1990 1991 1992 1993 1994 1995 1996 All<br />
Austria 4 4 4 6 6 9 16 16 65<br />
Belgium 1 1 1 5 13 14 15 14 64<br />
Denmark 3 3 5 14 24 29 36 34 148<br />
F<strong>in</strong>land 0 0 0 0 1 1 1 1 4<br />
France 0 0 1 8 17 20 18 18 82<br />
Germany 51 53 68 224 605 655 627 584 2867<br />
Italy 36 38 40 46 61 62 64 62 409<br />
Luxembourg 1 1 1 2 4 4 3 3 19<br />
Ne<strong>the</strong>rlands 0 0 0 1 1 2 3 3 10<br />
Portugal 1 1 2 3 3 2 3 3 18<br />
Spa<strong>in</strong> 43 45 47 50 52 52 51 51 391<br />
Sweden 0 0 1 1 1 1 1 1 6<br />
All 140 146 170 360 789 852 840 791 4083<br />
Asset size ECU m 1989 1990 1991 1992 1993 1994 1995 1996 All<br />
1 - 99.9 2 2 3 12 26 25 27 23 120<br />
100 - 199.9 4 3 4 22 69 76 61 50 289<br />
200 - 299.9 4 5 7 23 89 88 77 61 354<br />
300 - 499.9 11 12 13 38 132 135 124 108 573<br />
500 - 999.9 32 31 34 84 215 244 240 232 1112<br />
1,000 - 2,499.9 45 48 57 113 169 181 190 194 997<br />
2,500 - 4,999.9 24 25 28 38 52 61 72 72 372<br />
5,000 + 18 20 24 30 36 41 47 50 266<br />
All 140 146 170 360 789 852 840 791 4083<br />
28
Table 3 Scale economies for European sav<strong>in</strong>gs banks, 1989-1996<br />
1989 1990 1991 1992 1993 1994 1995 1996 All<br />
Austria 0.931* 0.929* 0.932* 0.931* 0.921* 0.932* 0.918* 0.912* 0.922*<br />
Belgium 0.882* 0.882* 0.881* 0.914* 0.944* 0.946* 0.939* 0.923* 0.933*<br />
Denmark 0.980* 0.990* 0.981* 1.029* 1.030* 1.030* 1.034* 1.033* 1.028*<br />
F<strong>in</strong>land -- -- -- -- 0.915* 0.908* 0.904* 0.890* 0.904*<br />
France -- -- 0.885* 0.896* 0.886* 0.881* 0.872* 0.871* 0.879*<br />
Germany 0.909* 0.907* 0.907* 0.926* 0.931* 0.929* 0.927* 0.924* 0.926*<br />
Italy 0.902* 0.901* 0.902* 0.908* 0.912* 0.913* 0.908* 0.904* 0.907*<br />
Luxembourg 0.842* 0.828* 0.827* 0.906* 0.977* 0.969* 0.928* 0.924* 0.929*<br />
Ne<strong>the</strong>rlands -- -- -- 0.924* 0.905* 0.999* 0.990* 0.997* 0.979*<br />
Portugal 0.943* 0.953* 1.002 0.922* 0.913* 0.883* 0.910* 0.907* 0.923*<br />
Spa<strong>in</strong> 0.915* 0.913* 0.913* 0.912* 0.906* 0.902* 0.900* 0.899* 0.907*<br />
Sweden -- -- 0.878* 0.891* 0.881* 0.875* 0.895* 0.878* 0.883*<br />
All 0.911* 0.909* 0.910* 0.924* 0.930* 0.929* 0.927* 0.924* 0.925*<br />
Assets Size (ECU million)<br />
1 - 99.9 100 - 199.9 200 - 299.9 300 – 499.9 500 - 999.9 1,000 - 2,499.9 2,500 - 4,999.9 5,000 + All<br />
Austria -- 0.994 0.992 0.929* 0.890* 0.949* 0.913* 0.830* 0.922*<br />
Belgium 1.096* -- 0.939* 0.922* 0.880* 0.883* 0.869* 0.848* 0.933*<br />
Denmark 1.082* 1.020* 0.972* 0.961* 0.903* 0.891* -- -- 1.028*<br />
F<strong>in</strong>land -- -- -- -- -- 0.904* -- -- 0.904*<br />
France -- -- 0.956* -- 0.929* 0.909* 0.876* 0.846* 0.879*<br />
Germany 1.079* 1.027* 0.985* 0.943* 0.905* 0.898* 0.899* 0.886* 0.926*<br />
Italy 1.103* 0.997* 0.963* 0.934* 0.901* 0.893* 0.897* 0.868* 0.907*<br />
Luxembourg 1.079* 1.001 0.978* 0.961* -- -- -- 0.818* 0.929*<br />
Ne<strong>the</strong>rlands -- 1.088* -- -- 0.937* -- -- 0.919* 0.979*<br />
Portugal 1.089* 1.001 -- 0.959* 0.938* 0.936* -- 0.842* 0.923*<br />
Spa<strong>in</strong> 1.097* 1.035* 1.004 0.961* 0.910* 0.895* 0.890* 0.861* 0.907*<br />
Sweden -- -- -- -- -- -- -- 0.883* 0.883*<br />
All 1.086* 1.026* 0.981* 0.943* 0.905* 0.898* 0.895* 0.866* 0.925*<br />
Assets Size (ECU m) 1989 1990 1991 1992 1993 1994 1995 1996 All<br />
1 – 99.9 1.104* 1.103* 1.096* 1.085* 1.086* 1.087* 1.083* 1.084* 1.086*<br />
100 – 199.9 1.024* 1.028* 1.026* 1.031* 1.021* 1.023* 1.031* 1.032* 1.026*<br />
200 – 299.9 0.977* 0.987 0.993 0.992 0.979* 0.976* 0.981* 0.986 0.981*<br />
300 – 499.9 0.960* 0.954* 0.951* 0.953* 0.939* 0.938* 0.942* 0.945* 0.943*<br />
500 – 999.9 0.907* 0.904* 0.907* 0.911* 0.904* 0.903* 0.904* 0.905* 0.905*<br />
1,000 – 2,499.9 0.901* 0.900* 0.898* 0.897* 0.896* 0.899* 0.898* 0.898* 0.898*<br />
2,500 – 4,999.9 0.893* 0.895* 0.895* 0.898* 0.893* 0.894* 0.896* 0.894* 0.895*<br />
5,000 + 0.872* 0.872* 0.873* 0.870* 0.865* 0.862* 0.863* 0.862* 0.866*<br />
All 0.911* 0.909* 0.910* 0.924* 0.930* 0.929* 0.927* 0.924* 0.925*<br />
Note: *denotes statistically significantly different <strong>from</strong> 1.0 at <strong>the</strong> 5% level<br />
29
Table 4 Mean <strong>in</strong>efficiency levels for European sav<strong>in</strong>gs banks, 1989-1996<br />
1989 1990 1991 1992 1993 1994 1995 1996 All<br />
Austria 0.212 0.207 0.228 0.229 0.201 0.200 0.193 0.190 0.202<br />
Belgium 0.402 0.391 0.440 0.274 0.256 0.249 0.256 0.250 0.262<br />
Denmark 0.199 0.222 0.253 0.216 0.205 0.220 0.215 0.227 0.219<br />
F<strong>in</strong>land -- -- -- -- 0.292 0.337 0.329 0.318 0.319<br />
France -- -- 0.275 0.221 0.225 0.234 0.234 0.233 0.231<br />
Germany 0.216 0.214 0.215 0.216 0.217 0.209 0.212 0.212 0.213<br />
Italy 0.222 0.226 0.221 0.221 0.220 0.231 0.232 0.222 0.225<br />
Luxembourg 0.209 0.219 0.230 0.259 0.239 0.244 0.316 0.272 0.256<br />
Ne<strong>the</strong>rlands -- -- -- 0.212 0.223 0.253 0.269 0.268 0.255<br />
Portugal 0.349 0.372 0.255 0.303 0.311 0.251 0.285 0.275 0.292<br />
Spa<strong>in</strong> 0.230 0.231 0.240 0.235 0.232 0.230 0.228 0.232 0.232<br />
Sweden -- -- 0.171 0.176 0.165 0.178 0.179 0.165 0.172<br />
All 0.223 0.225 0.227 0.221 0.219 0.214 0.216 0.216 0.218<br />
Assets Size (ECU million)<br />
1 - 99.9 100 - 199.9 200 - 299.9 300 – 499.9 500 – 999.9 1,000 - 2,499.9 2,500 - 4,999.9 5,000 + All<br />
Austria -- 0.200 0.204 0.196 0.166 0.226 0.183 0.204 0.202<br />
Belgium 0.200 -- 0.230 0.219 0.264 0.250 0.389 0.256 0.262<br />
Denmark 0.209 0.223 0.233 0.231 0.225 0.208 -- -- 0.219<br />
F<strong>in</strong>land -- -- -- -- -- 0.319 -- -- 0.319<br />
France -- -- 0.221 -- 0.228 0.224 0.233 0.236 0.231<br />
Germany 0.195 0.207 0.210 0.219 0.215 0.211 0.208 0.210 0.213<br />
Italy 0.211 0.212 0.220 0.229 0.231 0.219 0.219 0.222 0.225<br />
Luxembourg 0.169 0.248 0.477 0.394 -- -- -- 0.240 0.256<br />
Ne<strong>the</strong>rlands -- 0.297 -- -- 0.231 -- -- 0.254 0.255<br />
Portugal 0.169 0.203 -- 0.251 0.284 0.347 -- 0.257 0.292<br />
Spa<strong>in</strong> 0.230 0.232 0.240 0.221 0.218 0.235 0.251 0.226 0.232<br />
Sweden -- -- -- -- -- -- -- 0.172 0.172<br />
All 0.208 0.212 0.215 0.220 0.218 0.218 0.222 0.221 0.218<br />
Assets Size (ECU m) 1989 1990 1991 1992 1993 1994 1995 1996 All<br />
1 - 99.9 0.210 0.233 0.199 0.194 0.203 0.210 0.211 0.214 0.208<br />
100 - 199.9 0.215 0.215 0.226 0.212 0.213 0.212 0.208 0.213 0.212<br />
200 - 299.9 0.214 0.215 0.248 0.223 0.217 0.211 0.217 0.209 0.215<br />
300 - 499.9 0.228 0.236 0.229 0.223 0.223 0.214 0.220 0.219 0.220<br />
500 - 999.9 0.217 0.221 0.220 0.220 0.218 0.215 0.218 0.218 0.218<br />
1,000 - 2,499.9 0.227 0.226 0.230 0.223 0.222 0.213 0.214 0.215 0.218<br />
2,500 - 4,999.9 0.231 0.229 0.228 0.224 0.220 0.225 0.215 0.217 0.222<br />
5,000 + 0.218 0.217 0.223 0.231 0.221 0.215 0.224 0.220 0.221<br />
All 0.223 0.225 0.227 0.221 0.219 0.214 0.216 0.216 0.218<br />
30
Table 5 Logistic parameter estimates: determ<strong>in</strong>ants of sav<strong>in</strong>gs banks <strong>in</strong>efficiency<br />
Variable Coefficient Standard Error T-ratio<br />
Constant 0.2841 0.00340 83.463<br />
TASSET 0.0012 0.00042 2.774<br />
CRATIO -0.0307 0.01406 -2.185<br />
ROAA -0.3267 0.11105 -2.942<br />
NL/TASSET -0.0936 0.00374 -24.999<br />
OBS/TASSET -0.0052 0.00479 -1.089<br />
LA/C&SF 0.0507 0.00404 12.570<br />
Number of observations 4088.0<br />
Log likelihood function 8338.5<br />
31
APPENDIX<br />
Table A1 Maximum likelihood parameter estimates for European sav<strong>in</strong>gs banks us<strong>in</strong>g FF stochastic<br />
cost frontier<br />
Variable<br />
Para<br />
mete<br />
r<br />
Coefficie<br />
nt<br />
Standard<br />
Error<br />
T-<br />
Value<br />
Variable<br />
Para<br />
mete<br />
r<br />
Coefficie<br />
nt<br />
Standard<br />
Error<br />
T-<br />
Value<br />
Constant α0 1.66480 0.05306 31.373 cos (z1) a1 0.01275 0.00439 2.901<br />
lnQ1 α1 0.51787 0.01682 30.783 s<strong>in</strong> (z1) b1 -0.01828 0.00367 -4.987<br />
lnQ2 α2 0.49463 0.01522 32.497 cos (z2) a2 0.00703 0.00431 1.632<br />
lnQ3 α3 0.01489 0.01039 1.433 s<strong>in</strong> (z2) b2 0.02513 0.00391 6.424<br />
lnP1 β1 0.36888 0.02361 15.622 cos (z3) a3 -0.01959 0.00498 -3.935<br />
lnP2 β2 0.58789 0.02225 26.417 s<strong>in</strong> (z3) b3 0.01207 0.00419 2.884<br />
lnQ1 lnQ1 /2 δ11 -0.01899 0.00347 -5.480 cos (z1+z1) a11 0.00794 0.00358 2.219<br />
lnQ1 lnQ2 δ12 -0.01995 0.00217 -9.213 s<strong>in</strong> (z1+z1) b11 -0.01347 0.00342 -3.942<br />
lnQ1 lnQ3 δ13 0.00201 0.00193 1.040 cos (z1+z2) a12 -0.02179 0.00504 -4.327<br />
lnQ2 lnQ2 /2 δ22 -0.01991 0.00311 -6.407 s<strong>in</strong> (z +z2) b12 0.00598 0.00418 1.429<br />
lnQ2 lnQ3 δ23 -0.01570 0.00161 -9.726 cos (z1+z3) a13 0.01757 0.00385 4.563<br />
lnQ3 lnQ3 /2 δ33 0.00573 0.00168 3.407 s<strong>in</strong> (z1+z3) b13 0.02723 0.00429 6.345<br />
lnP1 lnP1 /2 γ11 0.01158 0.00539 2.150 cos (z2+z2) a22 0.00272 0.00351 0.775<br />
lnP1 lnP2 γ12 -0.01017 0.00372 -2.736 s<strong>in</strong> (z2+z2) b22 0.00235 0.00338 0.696<br />
lnP2 lnP2 /2 γ22 0.00493 0.00129 3.822 cos (z2+z3) a23 -0.01345 0.00429 -3.134<br />
lnP1 lnQ1 ρ11 0.04127 0.00394 10.476 s<strong>in</strong> (z2+z3) b23 -0.03347 0.00410 -8.163<br />
lnP1 lnQ2 ρ12 -0.02049 0.00398 -5.150 cos (z3+z3) a33 0.00440 0.00264 1.666<br />
lnP1 lnQ3 ρ13 -0.01913 0.00279 -6.850 s<strong>in</strong> (z3+z3) b33 0.00264 0.00322 0.820<br />
lnP2 lnQ1 ρ21 -0.03700 0.00359 -10.292 cos (z+z1+z2) a112 0.00504 0.00316 1.595<br />
lnP2 lnQ2 ρ22 0.04554 0.00336 13.539 s<strong>in</strong> (z1+z1+z2) b112 -0.00027 0.00350 -0.077<br />
lnP2 lnQ3 ρ23 0.01519 0.00302 5.023 cos (z1+z1+z3) a113 -0.00830 0.00376 -2.207<br />
T τ -0.00419 0.00554 -0.756 s<strong>in</strong> (z1+z1+z3) b113 0.01632 0.00369 4.426<br />
T*T τ11 -0.00156 0.00028 -5.503 cos (z1+z2+z2) a122 -0.00876 0.00345 -2.543<br />
lnQ1T ψ1τ -0.00247 0.00097 -2.545 s<strong>in</strong> (z1+z2+z2) b122 -0.00731 0.00342 -2.136<br />
lnQ2T ψ2τ 0.00232 0.00083 2.790 cos (z1+z2+z3) a123 0.01670 0.00456 3.663<br />
lnQ3T ψ3τ -0.00062 0.00074 -0.838 s<strong>in</strong> (z1+z2+z3) b123 -0.00449 0.00479 -0.937<br />
lnP1T θ1τ 0.01230 0.00124 9.881 cos (z1+z3+z3) a133 -0.00881 0.00344 -2.559<br />
lnP2T θ2τ -0.01514 0.00131 -11.555 s<strong>in</strong> (z1+z3+z3) b133 0.00232 0.00359 0.647<br />
lnP3 β3 0.04323 0.01224 3.532 cos (z2+z2+z3) a223 0.00645 0.00348 1.851<br />
lnP1lnP3 γ13 -0.00140 0.00187 -0.749 s<strong>in</strong> (z2+z2+z3) b223 0.00246 0.00402 0.611<br />
lnP2lnP3 γ23 0.00524 0.00212 2.472 cos (z2+z3+z3) a233 -0.01323 0.00330 -4.006<br />
lnP3lnP3 γ33 -0.00384 0.00254 -1.512 s<strong>in</strong> (z2+z3+z3) b233 -0.00095 0.00389 -0.244<br />
lnP3lnQ1 ρ31 -0.00427 0.00356 -1.199 σ²u/ 2.94580 0.10190 28.909<br />
σ²v<br />
lnP3lnQ2 ρ32 -0.02506 0.00668 -3.751 σ²v 0.11419 0.00089 127.80<br />
lnP3lnQ3 ρ33 0.00394 0.00345 1.142<br />
lnP3T θ3τ 0.00284 0.00120 2.367<br />
32