Benchmarking and Firm Heterogeneity in Electricity Distribution: A Latent Class Analysis of Germany

In January 2009 Germany introduced incentive regulation for the electricity distribution sector based on results obtained from econometric and nonparametric benchmarking analysis. One main problem for the regulator in assigning the relative efficiency scores are unobserved firm-specific factors such as network and technological differences. Comparing the efficiency of different firms usually assumes that they operate under the same production technology, thus unobserved factors might be inappropriately understood as inefficiency. To avoid this type of misspecification in regulatory practice estimation is carried out in two stages: in a first stage observations are classified into two categories according to the size of the network operators. Then separate analyses are conducted for each sub-group. This paper shows how to disentangle the heterogeneity from inefficiency in one step, using a latent class model for stochastic frontiers. As the classification is not based on a priori sample separation criteria it delivers more robust, statistical significant and testable results. Against this backround we analyze the level of technical efficiency of a sample of 200 regional and local German electricity distribution companies for a balanced panel data set (2001-2005). Testing the hypothesis if larger distributors operate under a different technology than smaller ones we assess if a single step latent class model provides new insights to the use of benchmarking approaches within the incentive regulation schemes.Stochastic frontiers, latent class model, electricity distribution, incentive regulation

Potential Gains from Mergers in Local Public Transport: An Efficiency Analysis Applied to Germany

We analyze potential gains from hypothetical mergers in local public transport using the non-parametric Data Envelopment Analysis with bias corrections by means of bootstrapping. Our sample consists of 41 public transport companies from Germany's most densely populated region, North Rhine-Westphalia. We merge them into geographically meaningful, larger units that operate partially on a joint tram network. Merger gains are then decomposed into individual technical efficiency, synergy and size effects following the methodology of Bogetoft and Wang [Bogetoft, P., Wang, D., 2005. Estimating the Potential Gains from Mergers. Journal of Productivity Analysis, 23(2), 145-171]. Our empirical findings suggest that substantial gains up to 16 percent of factor inputs are present, mainly resulting from synergy effects.Merger, Public Transport, Efficiency, Data Envelopment Analysis

Next Stop: Restructuring?: A Nonparametric Efficiency Analysis of German Public Transport Companies

In this paper, we present a nonparametric comparative efficiency analysis of 179 communal public transport bus companies in Germany (1990-2004). We apply both deterministic data envelopment analysis (DEA) and bootstrapping to test the robustness of our estimates and to test the hypothesis of global and individual constant returns to scale. We find that the average technical efficiency of German bus companies is relatively low. We observe that the industry appears to be characterized by increasing returns to scale for smaller companies. These results would imply increasing pressure on bus companies to restructure.Public transport, buses, efficiency analysis, nonparametric methods, DEA, bootstrapping

"Kyrios” As Designation for the Oral Tradition Concerning Jesus (Paradosis and Kyrios)

The work of the form-critics on the Gospel has directed our A attention more than ever before to the historical development of the material of the tradition, which took place before the fixing of our Gospels in writing. Collections of single or several words of Jesus, and narratives about Jesus, were establishing themselves already in the early Church, and were passed on by it. How far this tradition was already in part written down, or, as with the oldest Jewish traditions, was only orally transmitted, is not a question of importance for us here, but in any case it could never be solved with certainty. That is also true, as M. Dibelius has rightly stressed, of the much quoted "Q source”. It is indeed very probable that already before the composition of our Gospels, there were smaller writings, above all collections of words of Jesus, but it is in no way possible to define or demarcate them more exactly. On principle, this whole stream of tradition, whether it is transmitted in written or oral fashion, in so far as it is not yet channelled in our Gospels, can and must be handled as a unit. When in the title we speak of an "oral” tradition concerning Jesus, we mean simply the tradition concerning Jesus which existed before the Gospels. Similarly, in the Jewish tradition of the Old Testament law, the interpretations of the law were at first orally handed down from Rabbi to pupil, and then later written, but neither the fact of this taking place, nor the time when it took place, are of any fundamental importance for this Jewish traditio

Overcoming Data Limitations in Nonparametric Benchmarking: Applying PCA-DEA to Natural Gas Transmission

This paper provides an empirical demonstration for a practical approach of efficiency evaluation against the background of limited data availability in some regulated industries. Here, traditional DEA may result in a lack of discriminatory power when high numbers of variables but only limited observations are available. We apply PCA-DEA for radial efficiency measurement to US natural gas transmission companies in 2007. This allows us to reduce dimensions of the optimization problem while maintaining most of the variation in the original data. Our results suggest that the PCA-DEA methodology reduces the probability of over-estimation of the individual firm-specific performance. It also allows for a large number of original variables without substantially reducing the discriminatory power of the model.Efficiency analysis, DEA, PCA, company regulation, natural gas transmission

Fine-Grain Iterative Compilation for WCET Estimation

Compiler optimizations, although reducing the execution times of programs, raise issues in static WCET estimation techniques and tools. Flow facts, such as loop bounds, may not be automatically found by static WCET analysis tools after aggressive code optimizations. In this paper, we explore the use of iterative compilation (WCET-directed program optimization to explore the optimization space), with the objective to (i) allow flow facts to be automatically found and (ii) select optimizations that result in the lowest WCET estimates. We also explore to which extent code outlining helps, by allowing the selection of different optimization options for different code snippets of the application

Unobserved Heterogeneity and International Benchmarking in Public Transport

We analyze the technical efficiency of German and Swiss urban public transport companies by means of SFA. In transport networks we might face different network structures or complexities, not observed, but influencing the production process. The unobserved factors are typically modeled as separable factors. However, we argue that the entire production process is organized around different network structures. Therefore, they are inevitably non-separable from the observed inputs and outputs. The adopted econometric model is a random coefficient stochastic frontier model. We estimate an input distance function for the years 1991 to 2006. The results underline the presence of unobserved non-separable factors.

L'Evangile Johannique et l'Histoire du Salut

Si nous énoncions notre sujet sous forme d'une question: l'évangile johannique connaît-il une histoire du salut, nous serions tentés, de prime abord, d'y donner une réponse négative. En effet, le quatrième évangile ne se distingue-t il pas des autres évangiles précisément par le fait que tout se passe, ici, en dehors d'une histoire ‘horizontale'? Ne s'agit-il pas d'un ‘nunc aeternum', d'une irruption du ‘tout autre' dans chaque instant, d'une histoire dont le symbole ne serait pas la ligne, mais le point? Le prologue de cet évangile ne place-t-il pas, à priori, la pensée johannique sur un plan opposé à celui de l'histoire du salut? L'affirmation concernant la relation entre Jésus et Jean-Baptiste à la fin de ce prologue: ‘celui qui vient après moi a été avant moi, car il a été le premier par rapport à moi', ne prouve-t-elle pas que Jésus-Christ, pour cet évangéliste, signifie ‘fin de l'histoire'? La déclaration du Christ johannique au chap. viii. 58: ‘avant qu'Abraham ne füt, je suis', ne confirme-t-elle pas que la perspective n'est plus celle de l'histoire du salut? D'autre part, la tension entre ‘ce qui est déjà accompli' et ‘ce qui n'est pas encore achevé', cette tension si caractéristique de toute la pensée du Nouveau Testament et qui marque une évolution temporelle, ne disparaît-elle pas dans notre évangile, puisque tout y est accompli en Christ? Le jugement qui a lieu déjà (chap. xii. 31, νυν κρίσıς έστίν), la résurrection déjà réalisée (chap. xi. 25), ne mettent-ils pas en évidence que l'eschatologie johannique n'est plus une eschatologie temporelle dans le sens d'une histoire du salut

Efficiency Analysis of German Electricity Distribution Utilities : Non-Parametric and Parametric Tests

This paper applies parametric and non-parametric and parametric tests to assess the efficiency of electricity distribution companies in Germany. We address traditional issues in electricity sector benchmarking, such as the role of scale effects and optimal utility size, as well as new evidence specific to the situation in Germany This paper applies parametric and non-parametric and parametric tests to asses the efficiency of electricity distribution companies in Germany. We use labor, capital, and peak load capacity as inputs, and units sold and the number of customers as output. The data covers 307 (out of 553) German electricity distribution utilities. We apply a data envelopment analysis (DEA) with constant returns to scale (CRS) as the main productivity analysis technique, whereas stochastic frontier analysis (SFA) with distance function is our verification method. The results suggest that returns to scale play a minor role; only very small utilities have a significant cost advantage. Low customer density is found to affect the efficiency score significantly 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. --Efficiency analysis,econometric methods,electricity distribution,benchmarking,Germany