Efficiency analysis of German electricity distribution utilities – non-parametric and parametric tests

This study applies non-parametric and parametric tests to assess the efficiency of electricity distribution companies in Germany. Traditional issues in electricity sector benchmarking are addressed, such as the role of scale effects and optimal utility size, as well as new evidence specific to the situation in Germany. Labour, capital, and peak load capacity are used as inputs, and units sold and the number of customers as output. The data cover 307 (out of 553) German electricity distribution utilities. A data envelopment analysis (DEA) is applied with constant returns to scale (CRS) as the main productivity analysis technique, whereas stochastic frontier analysis (SFA) with distance function is the verification method. The results suggest that returns to scale play but a minor role; only very small utilities have a significant cost advantage. Low customer density is found to affect the efficiency score significantly, in particular in the lower third of all observations. Surprisingly, East German utilities feature a higher average efficiency than their West German counterparts. The correlation tests imply a high coherence of the results.     

On the (in)efficiency of Swiss hospitals

The efficiency of hospitals is of interest to health insurers, government authorities and hospital management itself. However, econometric methods for determining (in)efficiency have severe drawbacks since hospitals are multiproduct firms and because the duality between production and cost functions cannot be assumed. In this work, non-parametric, deterministic data envelopment analysis (DEA) is used to measure the relative inefficiency of 89 Swiss hospitals covering the years 1993–1996 (310 observations). Special attention is given to the role of patient days in the production of health. The findings depend on whether patient days are viewed as an input of patient time or as an output, as in previous studies. While the probability of a unit being inefficient cannot be explained using the available data, the degree of overall inefficiency is shown to significantly depend on the financial incentives faced by management, in particular due to subsidization. Private hospitals do not seem to be less inefficient than public ones; however, this may be caused by their ‘overusing’ inputs that in fact are valued as amenities by patients. This consideration points to an important limitation in applying the purely quantitative criteria of DEA to hospitals.     

Survey on technical efficiency in higher education: A meta-fractional regression analysis

There has been remarkable growth in the number of studies using data envelopment analysis (DEA) in research on higher education. Heterogeneous DEA models have been applied in assessing the performance of higher education institutions (HEIs), and the multi-faceted production process of higher education has further motivated the extension and improvement of the DEA approach. The present study conducts a meta-regression analysis of 109 published DEA applications in higher education at different levels of analysis to provide a better understanding of the relationship between the efficiency results and the attributes of the studies implemented in different nations.     

A BROAD PERFORMANCE BENCHMARK BASED ON CITIZENS' PREFERENCES: THE CASE OF SWEDISH PUBLIC TRANSPORTATION

ABSTRACT ** :  Benchmarks have been recommended for assessing the relative performance of local government services. However, these are often narrowly defined and therefore ignore important welfare dimensions. This paper proposes a framework for benchmarking based on a combination of production and cost characteristics and citizens' subjective perceptions. An evaluation consisting of Data Envelopment Analysis (DEA) and different regression models is applied on all 21 Swedish regional public transport authorities, covering the period 2002–2006 (n = 103). The results indicate that the industry as a whole is about 70% efficient and that efficiency can be improved by increasing the sizes of the urban and the bus vehicle-km shares. The optimal ownership structure is to have one large owner combined with about 25 small owners.     

Modelling superannuation fund management function as a two-stage process for overall and stage-level performance appraisal

We assess superannuation fund performance in a multi-dimensional framework by conceptualizing its management function as a serially linked two sub-process; operational management (OM) and portfolio management (PM). The procedure that we adopt is data envelopment analysis (DEA). We express overall efficiency as a weighted average of the two sub-process efficiencies and assess overall efficiency conditional on their relative importance. We demonstrate application of our model using a sample of Australian superannuation funds. By appraising performance in two sample periods; crisis (2008) and relatively non-crisis (2014), we show that some findings of previous studies may be explained further through the proposed multi-stage framework. The best overall performer in 2008 is public sector funds and in 2014 it is corporate funds. Decomposition of overall efficiency reveals that public sector funds, on average, outperform all other fund categories in OM. However, no specific fund category dominates PM performance in both assessment periods. The driving force behind the observed inverse association between superannuation fund size and performance appears to be PM performance. Number of investment options offered is not associated with overall, OM and PM performance. Here, we demonstrate that performance appraisal from different aspects of management provide insightful information to superannuation fund managers.     

Measuring Efficiency: A Comparison of Multilevel Modelling and Data Envelopment Analysis in the Context of Higher Education

Data envelopment analysis (DEA) and multilevel modelling (MLM) are applied to a data set of 54,564 graduates from UK universities in 1993 to assess whether the choice of technique affects the measurement of universities’ performance. A methodology developed by Thanassoulis and Portela (2002; Education Economics, 10(2), pp. 183–207) allows each individual's DEA efficiency score to be decomposed into two components: one attributable to the university at which the student studied and the other attributable to the individual student. From the former component, a measure of each institution's teaching efficiency is derived and compared to the university effects from various multilevel models. The comparisons are made within four broad subjects: pure science, applied science, social science and arts. The results show that the rankings of universities derived from the DEA efficiencies which measure the universities’ own performance (i.e., having excluded the efforts of the individuals) are not strongly correlated with the university rankings derived from the university effects of the multilevel models. The data were also used to perform a university‐level DEA. The university efficiency scores derived from these DEAs are largely unrelated to the scores from the individual‐level DEAs, confirming a result from a smaller data set (Johnes, 2006a; European Journal of Operational Research, forthcoming). However, the university‐level DEAs provide efficiency scores which are generally strongly related to the university effects of the multilevel models.     

The internal market and hospital efficiency: a stochastic distance function approach

The UK internal market was one of the first European attempts to introduce a competitive mechanism in the provision of hospital services. The assumption was that competition would have led hospitals to increase efficiency in the use of their resources. The aim of this paper is to analyse the effectiveness of this kind of reform by measuring the changes in technical efficiency of a panel of 52 acute Scottish hospitals observed from 1991/92 to 1996/97. The time period covers the whole duration of the internal market and the sample contains a different mix of both trusts and non-trusts, where the former embed the proper working of the reform. The selected model is a stochastic output distance function that includes an interaction dummy variable to allow for parameters to change over time. The results show a structural break after which hospitals change not only the way in which they provide their services, but also the kind of services they provide, favouring the quicker treatment of patients on a day basis. No significant improvement in technical efficiency is detected instead over time, nor any significant difference in efficiency between trusts and non-trusts.     

基于三阶段超效率DEA的港口运行效率研究

港口作为国内和国际贸易的关键节点,如何提高其运行效率成为焦点话题.针对目前国内港口效率低下的问题,使用超效率DEA模型来测度2007—2016年我国主要沿海港口的运行效率,研究发现港口的超效率平均值呈上升趋势,个别年份存在明显的下滑现象.由于2016年是航运港口整合的关键一年,本文对2016年的港口数据单独采用三阶段超效率DEA方法进行效率测度,第一阶段利用超效率DEA模型得出的结果进行分析,第二阶段利用随机前沿模型(SFA)将影响港口效率的腹地GDP等环境变量纳入模型,尽可能剔除随机误差和外部环境对效率的影响.第三阶段使用调整后的投入产出值重新评估港口效率,获得更加准确的港口效率排名,与第一阶段的超效率结果比较发现,前后数值存在明显差异,除青岛港和上海港外其他港口都未达到DEA有效,港口效率提升的空间较大.最后基于吞吐量-效率矩阵将港口划分为精干型、强壮型、肥胖型和瘦弱型4种类型,针对性的对每种类型的港口提出改进建议.     

An international comparison of hospital efficiency: does institutional environment matter?

The consensus among many health economists is that no meaningful performance differences exist among for-profit and non-profit hospitals in the US, but this topic has continued to be a matter of academic, judicial, and public policy interest. A similar debate has ensued internationally, regarding the potential efficiency gains from privatization of public enterprises. In this paper, we examine empirical evidence from the public, highly regulated Norwegian hospital sector and the private, highly competitive and unregulated California hospital sector to ascertain whether institutional environment and level of market competition significantly affect the degree of productive efficiency in hospitals. We compare and discuss the productive efficiency of four similar sets of hospitals operating in different institutional and competitive environments. The four samples are carefully matched in the dimensions of sample size, hospital size, and average lengths of stay. Heterogeneity in output definition is used to control for other dimensions (casemix, age distribution of patients). We use Data Envelopment Analysis (DEA) to estimate and compare average long-run as well as short-run efficiency measures across groups. We find that scale and scope regulation of Norwegian hospitals improves long-run efficiency, primarily due to better utilization of capital.     

Ethnic Discrimination in Germany's Labour Market: A Field Experiment

Abstract. This paper studies ethnic discrimination in Germany's labour market with a correspondence test. We send two similar applications to each of 528 advertisements for student internships, one with a Turkish‐sounding and one with a German‐sounding name. A German name raises the average probability of a callback by about 14%. Differential treatment is particularly strong and significant in smaller firms at which the applicant with the German name receives 24% more callbacks. Discrimination disappears when we restrict our sample to applications including reference letters which contain favourable information about the candidate's personality. We interpret this finding as evidence for statistical discrimination.     

我国省域产学研合作效率及效率持续性——基于省域面板数据和DEA-Malmquist生产率指数法

以DEA模型、DEA-Malmquist生产率指数为研究工具,利用2006—2011年我国30个省(自治区、直辖市)的截面数据,对我国省域层面的产学研合作效率及效率持续性进行了实证分析。研究结果显示:我国产学研合作效率较低,产学研合作为DEA有效、弱DEA有效和非DEA有效的省区数量分别占样本省区总数的26.7%、10%和63.3%,其中非DEA有效的省区存在不同程度的投入冗余和产出不足问题;83.3%的样本省区的产学研合作全要素生产率有程度不同的增长,说明省域产学研合作效率保持了较好的增长态势,这种增长主要来自于技术进步,63.3%的样本省区的产学研合作技术效率呈下降趋势。最后,针对存在的问题提出政策建议,包括加强产学研合作、实现产学研成果的技术转移和有效应用、提高产学研合作的管理水平等。     

Economies of scale in the US computer industry: An empirical investigation using data envelopment analysis

Up to recently, economists have had no good tools to measure the returns to scale of individual corporations in an industry. Data envelopment analysis (DEA) is a linear programming technique for determining the efficiency frontier (the envelope) to the inputs and outputs of a collection of individual corporations or other productive units. While DEA offers an avenue for calculating the returns to scale of individual corporations, the approach has been riddled by mathematical complications arising from the possibility of alternate optima. The present paper develops theory for calculating the entire range of these alternate optima. Furthermore, in a quite ambitions empirical application, DEA is employed to determine the time path of returns to scale of all publicly held U.S. computer companies over the time period 1980–1991. For the great majority of companies, a unique time path is obtained; only in less than 4 percent of the linear programming calculations is an entire range of alternate optima obtained. The results indicate that the computer industry was polarized into two camps: large aging corporations with decreasing returns to scale, and swarms of small upstart companies with advanced technology exhibiting increasing returns to scale.     

Economic capacity estimation in fisheries: A non-parametric ray approach

Data envelopment analysis (DEA) has generally been adopted as the most appropriate methodology for the estimation of fishing capacity, particularly in multi-species fisheries. More recently, economic DEA methods have been developed that incorporate the costs and benefits of increasing capacity utilisation. One such method was applied to estimate the capacity utilisation and output of the Scottish fleet. By comparing the results of the economic and traditional DEA approaches, it can be concluded that many fleet segments are operating at or close to full capacity, and that the vessels defining the frontier are operating consistent with profit maximising behaviour.     

A ‘technically level playing-field’ profit efficiency analysis of enforced competition between publicly funded institutions

The study demonstrates how recent advances in the data envelopment analysis (DEA) of profit efficiency, and in combining DEA and stochastic frontier analysis (SFA) to measure producer performance, can be used to obtain a ‘technically level playing-field’ profit efficiency performance measure. A three-stage analysis is used to provide an empirical investigation of public-sector universities facing regulatory pressures to attain both profit efficiency and output quality. Stage one employs directional distance function analysis to decompose DEA profit efficiency measures into technical and allocative components. As these performance measures incorporate the impacts of managerial inefficiency, the operating environment and luck (statistical noise), stage two applies SFA to total (radial and non-radial) slacks to obtain a degree of disentanglement from the latter two impacts. The stage-two results are used to define a common environment and common luck scenario, thus permitting university producers’ inputs to be adjusted so as to reflect operation within this more level playing-field scenario. Stage three recomputes the first-stage DEA for this scenario, to yield an (input-focused) ‘technically level playing-field’ measure of profit efficiency that unifies the regulatory financial audit and output-quality indicators in a single, best-practice-benchmarked, performance measure.     

The efficiency of the Spanish police service: an application of the multiactivity DEA model

In this paper the efficiency of the Spanish Police Service is analysed using Data Envelopment Analysis (DEA). The analysis concentrates on the police activities related to the solving of crimes. The theoretical and empirical study of the police production function under this dimension leads to a consideration of the units analysed as centres which carry out their activities with nonidentical technologies and using common inputs. Accordingly, the multiactivity DEA model developed by Mar Molinero (Journal of the Operational Research Society, 47, 1996, 1273-9) is applied, one that is designed to estimate the efficiency of institutions which face several production functions using shared inputs. The results demonstrate the important differences that exist between the centres with respect to the distinct activities analysed, both as regards the efficiency rates and the factors which determine them.     

Measuring and explaining the efficiencies of the United Arab Emirates banking system

Using newly collected data from a survey distributed to all banks in the United Arab Emirates (UAE), this article measures economic efficiency in the banking industry, namely allocative, technical, pure technical and scale efficiency. Employing a nonparametric Data Envelopment Analysis (DEA) approach, the study estimates the efficiency for a cross section of the UAE banks in 2004. The results indicate that the dominant source of inefficiency in the UAE banking is stemming from allocative inefficiency rather than technical inefficiency. Furthermore, the main source of the relatively small size, technical inefficiency in the UAE banking industry is not the scale inefficiency but rather pure technical inefficiency. The results further indicate that the UAE banks are able to use their input resources more efficiently when they have more branches, and that newer banks are performing better than older banks on average. Moreover, the results also show that short experiences of employees affect efficiencies negatively and government ownership tends to reduce efficiency (as the government shares increase in the bank, the efficiency scores get lower). Finally, the most interesting results have to do with finding higher average efficiencies in banks that employ more women, more managers and less national citizens of the UAE.     

中国保险机构资金运用效率研究:基于资源型两阶段DEA模型

本文采用中国保险机构1999—2006年共246个样本数据,通过建立资源型两阶段DEA的效率评估模型,测算了保险机构资金运用过程的两阶段效率水平和变化轨迹。研究发现,中国保险业无论是资金筹集阶段和资金收益阶段的子效率,还是资金运用全过程的整体效率,得分都不高,全行业仍有大量的资源因管理不善而被浪费掉。与外资机构相比,中资保险机构在资金运用上的整体效率优势表现出"V"型趋势,具体表现为中资保险机构在资金筹集阶段的效率优势不再显著,在资金收益阶段则被外资机构反超并表现出一定效率差距。进一步的分析发现,虽然中资寿险机构在资金筹集阶段的效率占有一定优势,但在收益阶段的效率亟待提高,而中资财险机构在资金筹集阶段和收益阶段均面临着相当严峻的考验。     

基于DEA和因子分析法的安徽省物流发展现状实证分析--基于安徽省2011年各地市物流相关统计数据

基于DEA模型,通过建立物流投入指标,分析2011年安徽省16个地市的物流投入产出效率。结论表明：以合肥为代表的7个地市物流投入产出达到DEA有效;以阜阳为代表的9个地市存在投入和产出冗余;总体来看,安徽省物流投入产出平均总体效率、平均纯技术效率、平均规模效率分别为0.83、0.89、0.92,说明安徽省物流效率偏低的主要原因是纯技术效率偏低造成的,物流投入存在浪费现象,产出还有很大发展空间。为了提升物流效率,使用因子分析法对安徽省物流产业发展影响因素进行分析,根据3个主要影响因子,提出了物流发展改进策略。     

A comparative study of efficiency in European banking

This paper investigates whether there has been an improvement in and convergence of productive efficiency across European banking markets since the creation of the Single Internal Market. Using efficiency measures derived from DEA estimation, the determinants of European bank efficiency are evaluated using the Tobit regression model approach. The established literature on modelling the determinants of bank efficiency is then extended by recognizing the problem of the inherent dependency of DEA efficiency scores when used in regression analysis. To overcome the dependency problem, a bootstrapping technique is applied. Overall, the results suggest that since the EU's Single Market Programme there has been a small improvement in bank efficiency levels, although there is little evidence to suggest that these have converged. The results also suggest that inference on the determinants of bank efficiency drawn from non-bootstrapped regression analysis may be biased and misleading.     

Comparing structural efficiency of unbalanced subsamples: A resampling adaptation of data envelopment analysis

This paper investigates the performance of a bootstrapping enhanced DEA to measure the relative structural efficiency of unbalanced subsamples. Although this issue plays an important role in applied DEA, it is often ignored, resulting in misleading conclusions concerning relative efficiency. It is shown, that a reasampling approach to DEA can cope with this problem and also allows the use of pooled samples. The distribution of a statistic to test the hypotheses of equal structural efficiency is derived from Monte Carlo simulations and compared with the corresponding statistic calculated from standard DEA results. While the resampling variant of DEA justifies the use of the normal approximation, this is not the case for standard DEA.