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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 />

Nelson, R.A., (1984), ‘Regulation, capital v<strong>in</strong>tage, and technical change <strong>in</strong> <strong>the</strong> electric<br />

utility <strong>in</strong>dustry’, Review of Economics and Statistics, 66, (February), 59-69.<br />

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of stochastic frontier production functions’, Journal of Econometrics, 13, 67-82.<br />

25


Resti, A., (1997), ‘Evaluat<strong>in</strong>g <strong>the</strong> cost-efficiency of <strong>the</strong> Italian Bank<strong>in</strong>g system: What<br />

can be learned <strong>from</strong> <strong>the</strong> jo<strong>in</strong>t application of parametric and non-parametric<br />

techniques’, Journal of Bank<strong>in</strong>g and F<strong>in</strong>ance, Vol. 21, 221-250.<br />

Revell, J. (1989), The Future of Sav<strong>in</strong>gs Banks: A Study of Spa<strong>in</strong> and <strong>the</strong> Rest of<br />

Europe, Institute of European F<strong>in</strong>ance, Research Monographs <strong>in</strong> Bank<strong>in</strong>g and<br />

F<strong>in</strong>ance no. 8, (University of Wales, Bangor, UK: Institute of European F<strong>in</strong>ance)<br />

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depository f<strong>in</strong>ancial <strong>in</strong>stitution’, Journal of F<strong>in</strong>ance 32, 1251-1266.<br />

Spong, K., R.J. Sullivan and R. DeYoung, (1995), ‘What makes a bank efficient? - A<br />

look at f<strong>in</strong>ancial characteristics and bank management and ownership structure’,<br />

FRB of Kansas City Review, December, 1-19.<br />

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estimation’, Journal of Econometrics, 13, 57-66.<br />

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banks <strong>in</strong> Europe’, paper presented at <strong>the</strong> SUERF/CFS Colloquim, Franfurt, 15-17<br />

October<br />

White, H, (1980), ‘Us<strong>in</strong>g least squares to approximate unknown regression functions’,<br />

International Economic Review, vol. 21, pp. 149-170.<br />

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

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