   Imposing monotonicity on outputs in parametric distance function estimationsPerelman, Sergio  ; in Applied Economics (2011) Detailed reference viewed: 14 (4 ULg) Tracking the stepwise effects of regulatory reforms over time: a "back-door" approach; Perelman, Sergio ; in Applied Economics (2009), 41(2), 211-218 Most of the literature on the efficiency effects of regulatory reforms ignores the gradual nature of the implementation of these reforms. This article describes a new simple data manipulation that ... [more ▼] Most of the literature on the efficiency effects of regulatory reforms ignores the gradual nature of the implementation of these reforms. This article describes a new simple data manipulation that minimizes data requirements to measure econometrically the impact on efficiency of each stage of multi-stages regulatory reforms. The approach can easily be implemented using standard stochastic frontier software programs. It is illustrated with data on the Spanish port system, which went through a two-stage reform during the 1990s. [less ▲] Detailed reference viewed: 70 (17 ULg)Imposing monotonicity in parametric distance functions; Perelman, Sergio in Applied Economics (2008) Detailed reference viewed: 18 (9 ULg)Technical efficiency of European railways: a distance function approach; Perelman, Sergio in Applied Economics (2000), 32 This study has two principal objectives. The first objective is to measure and compare the performance of European railways. The second objective is to illustrate the usefulness of econometric distance ... [more ▼] This study has two principal objectives. The first objective is to measure and compare the performance of European railways. The second objective is to illustrate the usefulness of econometric distance functions in the analysis of production in multioutput industries, where behavioural assumptions such as cost minimization or profit maximization, are unlikely to be applicable. Using annual data on 17 railways companies during 1988± 1993, multioutput distance functions are estimated using corrected ordinary least squares (COLS). The resulting technical efficiency estimates range from 0.980 for the Netherlands to 0.784 for Italy, with a mean of 0.863. The distance function results are also compared with those obtained from single-output production functions, where aggregate output measures are formed using either total revenue or a Tornqvist index. The results obtained indicate substantial differences in parameter estimates and technical efficiency rankings, casting significant doubt upon the reliability of these single-output models, particularly when a total revenue measure is used to proxy aggregate output. [less ▲] Detailed reference viewed: 61 (2 ULg)Efficiency measurement, multiple-output technologies and distance functions: with application to European Railways; Perelman, Sergio in Applied Economics (2000), (32), 1967-1976 The single-output production function has long been regarded as one of the principle limitations of the econometric approach to technical efficiency measurement. If one wished to investigate efficiency in ... [more ▼] The single-output production function has long been regarded as one of the principle limitations of the econometric approach to technical efficiency measurement. If one wished to investigate efficiency in a multiple-output industry using econometric methods one would usually either: (a) aggregate outputs into a single index of output (e.g., total revenue or a multilateral Tornqvist output index); or (b) attempt to model the technology using a dual cost function. The first of these methods require that output prices be observable (and reflect revenue maximising behaviour), while the latter approach requires an assumption of cost-minimising behaviour. There are a number of instances, however, when neither of these requirements are met (the public sector contains many examples). In this study we outline the recently developed distance function solution to the multi-output problem. The method is illustrated using data on European railways. Output-orientated, input-orientated and constant returns to scale distance functions are estimated using corrected ordinary least squares. The distance function estimates are also compared with production function estimates involving aggregate output measures. These comparisons indicate that, for the case of European railways, a production function involving a multilateral Tornqvist output index exhibits substantially less aggregation bias relative to a production function that uses total revenue as a measure of aggregate output. [less ▲] Detailed reference viewed: 52 (1 ULg)Economic growth and exchange rate uncertaintyTharakan, Joseph in Applied Economics (1999) Detailed reference viewed: 37 (6 ULg) |
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