Effects of Specification Choices on Efficiency in DEA and SFA
Michael Koetter, Aljar Meesters
Efficiency and Productivity Growth: Modelling in the Financial Services Industry,
2013
Abstract
This chapter assesses the sensitivity of bank cost-efficiency scores obtained with stochastic frontier analysis and data envelopment analysis. We compare CE scores of either type for a large cross-country sample of EU banks from 1996 until 2010. The results show that CE measures differ considerably depending on specification choices across parametric and nonparametric methods. The chapter documents the reasons for these differences in terms of theoretical, sample, and further specification choices.
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ICT Adoption and Heterogeneity in Production Technologies: Evidence for Chilean Retailers
Gaaitzen J. de Vries, Michael Koetter
Oxford Bulletin of Economics and Statistics,
Nr. 4,
2011
Abstract
The adoption of information and communication technology (ICT) can have far-reaching effects on the nature of production technologies. Because ICT adoption is incomplete, especially in developing countries, different groups of firms will have different production technologies. We estimate a latent class stochastic frontier model, which allows us to test for the existence of multiple production technologies across firms and consider the associated implications for efficiency measures. We use a unique data set of Chilean retailers, which includes detailed information on ICT adoption. We find three distinct production technologies. The probability of membership in a more productive group is positively related to ICT use.
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Handling Losses in Translog Profit Models
J. W. B. Bos, Michael Koetter
Applied Economics,
Nr. 3,
2011
Abstract
In this article, we compare standard approaches used to handle losses in logarithmic profit models with a simple novel approach. We estimate translog stochastic profit frontiers, and discuss discriminatory power, rank stability and the precision of Profit Efficiency (PE) scores. Contrary to existing methods, our approach does not result in a loss of observations. Our new method enhances rank stability and discriminatory power, and improves the precision of PE scores.
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Technology Clubs, R&D and Growth Patterns: Evidence from EU Manufacturing
Claire Economidou, J. W. B. Bos, Michael Koetter
European Economic Review,
Nr. 1,
2010
Abstract
This paper investigates the forces driving output change in a panel of EU manufacturing industries. A flexible modeling strategy is adopted that accounts for: (i) inefficient use of resources and (ii) differences in the production technology across industries. With our model we are able to identify technical, efficiency, and input growth for endogenously determined technology clubs. Technology club membership is modeled as a function of R&D intensity. This framework allows us to explore the components of output growth in each club, technology spillovers and catch-up issues across industries and countries.
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Do All Countries Grow Alike?
Claire Economidou, J. W. B. Bos, Michael Koetter, James W. Kolari
Journal of Development Economics,
Nr. 1,
2010
Abstract
This paper investigates the driving forces of output change in 77 countries during the period 1970–2000. A flexible modeling strategy is adopted that accounts for (i) the inefficient use of resources, and (ii) different production technologies across countries. The proposed model can identify technical, efficiency, and input change for each of three endogenously determined regimes. Membership in these regimes is estimated, rather than determined ex ante. This framework enables explorations into the determinants of output growth and convergence issues in each regime.
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Effects of Heterogeneity on Bank Efficiency Scores
J. W. B. Bos, Michael Koetter, James W. Kolari, Clemens J. M. Kool
European Journal of Operational Research,
Nr. 1,
2009
Abstract
Bank efficiency estimates often serve as a proxy of managerial skill since they quantify sub-optimal production choices. But such deviations can also be due to omitted systematic differences among banks. In this study, we examine the effects of heterogeneity on bank efficiency scores. We compare different specifications of a stochastic cost and alternative profit frontier model with a baseline specification. After conducting a specification test, we discuss heterogeneity effects on efficiency levels, ranks and the tails of the efficiency distribution. We find that heterogeneity controls influence both banks’ optimal costs and profits and their ability to be efficient. Differences in efficiency scores are important for more than only methodological reasons. First, different ways of accounting for heterogeneity result in estimates of foregone profits and additional costs that are significantly different from what we infer from our general specification. Second, banks are significantly re-ranked when their efficiency is estimated with a specification other than the preferred, general specification. Third, the general specification gives the most reliable estimates of the probability of distress, although differences to the other specifications are low.
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The Stability of Bank Efficiency Rankings when Risk Preferences and Objectives are Different
Michael Koetter
European Journal of Finance,
Nr. 2,
2008
Abstract
We analyze the stability of efficiency rankings of German universal banks between 1993 and 2004. First, we estimate traditional efficiency scores with stochastic cost and alternative profit frontier analysis. Then, we explicitly allow for different risk preferences and measure efficiency with a structural model based on utility maximization. Using the almost ideal demand system, we estimate input- and profit-demand functions to obtain proxies for expected return and risk. Efficiency is then measured in this risk-return space. Mean risk-return efficiency is somewhat higher than cost and considerably higher than profit efficiency (PE). More importantly, rank–order correlation between these measures are low or even negative. This suggests that best-practice institutes should not be identified on the basis of traditional efficiency measures alone. Apparently, low cost and/or PE may merely result from alternative yet efficiently chosen risk-return trade-offs.
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Inflation and the Divergence of Relative Prices: Evidence from a Cointegration Analysis
Juliane Scharff
AStA - Advances in Statistical Analysis,
Nr. 2,
2007
Abstract
The relation between inflation and RPV plays a prominent role in explaining the costs of inflation. This study investigates whether the CPI subcategories drift apart more over a period of high inflation rates than during one of low inflation. The wider dispersion of the subcategories is reflected in an increasing number of common stochastic trends in the system of sub price indices. The results for US data as well as for cross-country comparisons indicate that the influence of inflation on the dispersion of relative prices cannot be revealed by counting cointegrating relations. Thus, the number of stochastic trends or cointegrating relations is not a reliable indicator for the distorting effect of inflation on the dispersion of relative prices.
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Measurement Matters — Alternative Input Price Proxies for Bank Efficiency Analyses
Michael Koetter
Journal of Financial Services Research,
Nr. 2,
2006
Abstract
Most bank efficiency studies that use stochastic frontier analysis (SFA) employ each bank’s own implicit input price when estimating efficient frontiers. But at the same time, most studies are based on cost and/or profit models that assume perfect input markets. Traditional input price proxies therefore contain at least substantial measurement error. We suggest here two alternative input market definitions to approximate exogenous input prices. We have access to Bundesbank data, which allows us to cover virtually all German universal banks between 1993 and 2003. The use of alternative input price proxies leads to mean cost efficiency that is significantly five percentage points lower compared to traditional input prices. Mean profit efficiency is hardly affected. Across models, small cooperative banks located in large western states perform best while large banks and those located in eastern states rank lowest.
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Quality of Service, Efficiency, and Scale in Network Industries: An Analysis of European Electricity Distribution
Christian Growitsch, Tooraj Jamasb, Michael Pollitt
IWH Discussion Papers,
Nr. 3,
2005
Abstract
Quality of service is of major economic significance in natural monopoly infrastructure industries and is increasingly addressed in regulatory schemes. However, this important aspect is generally not reflected in efficiency analysis of these industries. In this paper we present an efficiency analysis of electricity distribution networks using a sample of about 500 electricity distribution utilities from seven European countries. We apply the stochastic frontier analysis (SFA) method on multi-output translog input distance function models to estimate cost and scale efficiency with and without incorporating quality of service. We show that introducing the quality dimension into the analysis affects estimated efficiency significantly. In contrast to previous research, smaller utilities seem to indicate lower technical efficiency when incorporating quality. We also show that incorporating quality of service does not alter scale economy measures. Our results emphasise that quality of service should be an integrated part of efficiency analysis and incentive regulation regimes, as well as in the economic review of market concentration in regulated natural monopolies.
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