Semi-radial technical efficiency measurement

Semi-radial efficiency measurement combines technical efficiency, as captured by the classical Farrell measure, with an economically meaningful mix efficiency component. The semi-radial evaluation we propose proceeds in two steps. First, we build on the price interpretation of the generally accepted Koopmans efficiency notion to characterize appropriate benchmarks. Next, we present both a quantity-based distance measure and its dual (price-based) equivalent to evaluate the mix efficiency factor. The type of measures we propose may, e.g., be used to provide a price rationale for the Zieschang technical efficiency evaluation procedure.     

Measuring the efficiency of NBA teams: additive efficiency decomposition in two-stage DEA

This paper evaluates the efficiency of National Basketball Association (NBA) teams under a two-stage DEA framework. Applying the additive efficiency approach, we decompose overall team efficiency into first-stage wage efficiency and second-stage on-court efficiency and find out the individual endogenous weights for each stage. The empirical results show that NBA teams present a better performance on wage efficiency than for on-court efficiency, as on-court efficiency is influenced by many uncontrollable factors. Moreover, NBA teams, on average, tend to possess a higher weight on the first stage, suggesting that teams’ managers can enhance organizational efficiency more efficaciously by prudentially recruiting players.     

时间效益分析法在教学质量评价中的应用

文章在回顾教学质量评价方法的基础上 ,介绍了时间效益分析方法的基本原理并应用此方法 ,利用同一地区两所学校 95年中考成绩和 98年高考成绩对两所学校的教学质量进行了分析比较。文章最后还采用齐次马尔可夫链分析法和协方差分析方法对这两所学校的教学质量进行了评价 ,三种方法得出了相同的结论 ,从而验证了时间效益分析方法的可行性     

The hyperbolic-oriented efficiency measure as a remedy to infeasibility of super efficiency models

The infeasibility problem in traditional super efficiency models has been well established. A generalization of traditional input- or output-oriented super efficiency models, the directional distance function also suffers from infeasibility and related problems. The hyperbolic-oriented efficiency measure provides an alternative to the input-oriented, output-oriented, and directional efficiency measures in super efficiency models and it has the distinct advantage of eliminating the infeasibility problem for positive input/output data. We also show that using a hyperbolic orientation in a super efficiency model allows us to find feasible solutions for certain cases when the requirement for all data to be positive is relaxed. Further we demonstrate the hyperbolic orientated super efficiency method in an outlier detection application. Together, these results establish the use of the hyperbolic orientation in super efficiency analysis as a realistic alternative in practice.     

Aggregation of scale efficiency

In this article we generalize the aggregation theory in efficiency and productivity analysis by deriving solutions to the problem of aggregation of individual scale efficiency measures, primal and dual, into aggregate primal and dual scale efficiency measures of a group (e.g., industry). The new aggregation result is coherent with aggregation framework and solutions that were earlier derived for other related efficiency measures and can be used in practice for estimation of scale efficiency of an industry or other groups of firms within it.     

Measurement of multiperiod aggregative efficiency

This article proposes a new method for measuring an aggregative efficiency of multiple period production systems. Every organization or firm generates a time series of data that represent its performances in the resource utilization and output production over multiple periods, and often desires an aggregated measure of efficiency for several periods of interest. Data envelopment analysis (DEA) has become an accepted and well-known approach to evaluating efficiency performance in a wide range of cases. However, most of the DEA studies have dealt primarily with ways to gauge the efficiency of production in only a single period so this efficiency reflects the insufficient or partial performance of multiple period productions. The new method is developed through extensions of the concept of Debreu–Farrell technical efficiency and is applied to evaluating the efficiency of cable TV service units with 3-year data.     

Social efficiency in microfinance institutions

Microfinance institutions (MFIs) are a special case in the financial world. They have a double financial and social role and need to be efficient at both. In this paper, we try to measure the efficiency of MFIs in relation to financial and social outputs using data envelopment analysis. For the analysis of financial efficiency, we rely on existing literature for traditional financial institutions. To this we have added two indicators of social performance: impact on women and a poverty reach index. We have studied the relationship between social and financial efficiency, and the relationship between efficiency and other indicators, such as profitability. Other aspects studied are the relation between social efficiency and type of institution—Non-Governmental Organization (NGO)—, non-NGO, and the importance of geographical region of activity. The results reveal the importance of social efficiency assessment.     

On value efficiency

Value efficiency analysis (VEA) is a data envelopment analysis (DEA)-based approach that measures the efficiency of decision-making units, incorporating the decision maker's preferences explicitly. If the functional form of the value function is assumed pseudoconcave, then a tangent cone where the most preferred point is its vertex can be used to recognize value inefficient points. In this article, we consider the value function assumptions and show that the pseudoconcavity assumption can be extended to also cover nonsmooth value functions in VEA using a known class of limiting subdifferentials in nonsmooth analysis. The focus of this article is to show that the tangent cone approach to recognize value inefficient points is a valid approach even if the value function assumptions are more general than pseudoconcavity. Moreover, we show that continuity is needed in the case of true value efficiency.     

Multi-directional efficiency analysis of efficiency patterns in Chinese banks 1997–2008

DEA-type efficiency studies are often used to investigate levels of efficiencies, differences in those levels between subgroups within a data set and possible determinants of such differences. In the current paper we show how differences in the efficiency patterns between different subgroups within a data set can be investigated using the more recent MEA methodology.     

Technical efficiency and economies of scale: A non-parametric analysis of REIT operating efficiency

This study measures technical efficiency and economies of scale for real estate investment trusts (REITs) by employing data envelopment analysis (DEA), a linear-programming technique. Using data from the National Association of Real Estate Investment Trusts (NAREITs) for the years 1992–1996, we find that REITs are technically inefficient, and the inefficiencies are a result of both poor input utilization and failure to operate at constant returns to scale. With respect to scale inefficiency, most REITs are operating at increasing returns to scale, suggesting that REITs could improve performance through expansion. Moreover, we employ regression analysis to determine what characteristics influence the efficiency measures obtained. The results show that internal REIT management is positively related to all measures of efficiency. Increasing leverage is negatively related to REIT input utilization. Finally, increasing REIT diversification across property types enhances scale efficiency (SE) but reduces input usage efficiency.     

Concepts of proper efficiency

The centrol concept of proper efficiency has been largely that of Geoffrion. There are, however, other concepts, and this paper considers two of them, viz. those of Klinger and Kuhn and Tucker, in relationship to each other and to Geoffrion. This is done in terms of various properties which characterise the efficient sets. Geoffrion's concept is a global one, whereas the other two concepts are local ones, and their significance is somewhat different. This is examined specifically in the context of optimal solutions, where, for example, it is shown that Geoffrion and Kuhn and Tucker proper efficiency fails to meet an optimality condition, which is satisfied by Klinger proper efficiency.     

Fuzzy scores of technical efficiency

This paper suggests to extend scores of technical efficiency as used in, for example, Data Envelopment Analysis (DEA) to efficiency scores defined as so-called fuzzy intervals. Fuzzy scores allow the decision maker to use scores of technical efficiency in combination with other sources of available performance information e.g. expert opinions, key figures etc. In this sense fuzzy scores become formal images of the evaluation otherwise done implicitly by the decision maker and may therefore enhance a more consistent evaluation. It is shown how to rank a set of fuzzy scores.     

The selection efficiency of tournaments

We discuss tournaments in terms of their efficiency as probabilistic mechanisms that select high-quality alternatives (“players”) in a noisy environment. We characterize the selection efficiency of three such mechanisms – contests, binary elimination tournaments, and round-robin tournaments – depending on the shape of the distribution of players’ quality, the number of players, and noise level. The results have implications as to how, and under what circumstances, the efficiency of tournament-based selection can be manipulated.     

Resolving a strange case of efficiency

In a recent paper in the Journal of the Operational Research Society, Tone proposes an alternative to the Farrell cost efficiency index to avoid the ‘strange case’ problem in which firms with identical inputs and outputs but with input prices differing by some factor (eg, one has input prices twice another) will have the same Farrell cost efficiency. We provide an alternative cost efficiency indicator that avoids this problem, allows for decomposition into technical and allocative efficiency, and is easily estimated using DEA type models.     

A game theoretical model of DEA efficiency

Motivated by the inherent competitive nature of the DEA efficiency assessment process, some effort has been made to relate DEA models to game theory. Game theory is considered not only a more natural source of representing competitive situations, but also beneficial in revealing additional insights into practical efficiency analysis. Past studies are limited to connecting efficiency games to some particular versions of DEA models. The generalised DEA model considered in this study unifies various important DEA models and presents a basic formulation for the DEA family. By introducing a generalised convex cone constrained efficiency game model in assembling the generalised DEA model, a rigorous connection between game theory and the DEA family is established. We prove the existence of optimal strategies in the generalised efficiency game. We show the equivalence between game efficiency and DEA efficiency. We also provide convex programming models for determination of the optimal strategies of the proposed games, and show that the game efficiency unit corresponds to the non-dominated solution in its corresponding multi-objective programming problem. Our study largely extends the latest developments in this area. The significance of such an extension is for research and applications of both game theory and DEA.     

Allocative efficiency of technically inefficient production units

We discuss how to measure allocative efficiency without presuming technical efficiency. This is relevant when it is easier to introduce reallocations than improvements of technical efficiency. We compare the approach to the traditional one of assuming technical efficiency before measuring allocative efficiency. In particular, we develop necessary and sufficient conditions in the technology to ensure consistent measures, we suggest alternative interpretations of the approaches, and we relate them to motivational and organizational change perspectives.     

Solving the puzzles of structural efficiency

Since the concept of “structural efficiency” first appeared in Farrell [Farrell, M.J., 1957. The measurement of productive efficiency. Journal of the Royal Statistical Society, Series A, Part III 120, 253–281], attempts have been made to derive measures for the performance of a group of production units (often referred to an industry with many firms). Many empirical studies used the technical efficiency of an average unit to measure the structural efficiency of a group, but researchers have been puzzled by the discrepancies between the average of individual efficiency scores and the performance of the group as a whole. In this paper, we point out that the “shadow price model” provides a useful framework for understanding the economic meaning of the structural efficiency as well as its components. By recognizing these components, the puzzles related to the inconsistencies between the individual and group performance can be solved readily.     

Super efficiency evaluations based on potential slack

Super efficiency evaluations are introduced along the lines of the potential improvements approach in Journal of Productivity Analysis 12 (1999) 233. Both a reference selection and a related super efficiency index are defined. The new (potential slack) super efficiency index is compared to a Farrell-based super efficiency index (as in Management Science 39 (1993) 1261) with respect to convex envelopment technologies.     

Allocative efficiency in branch banking

Bank branch efficiency and organization change is analyzed using data from 50 savings bank branches in Sweden. First, technical and allocative efficiencies are analyzed, using non-priced and priced inputs. Secondly, by grouping the branches according to their organizational designation, efficiency is examined by level of service. Trends in performance over two time periods are also analyzed.