Mehdi Farsi

Regulation and Measuring Cost-Efficiency with Panel Data Models: Application to Electricity Distribution Utilities

This paper examines the performance of panel data models in measuring cost-efficiency of electricity distribution utilities. Different cost frontier models are applied to a sample of 59 utilities operating in Switzerland from 1988 to 1996. The estimated coefficients and inefficiency scores are compared across different specifications. The results indicate that while the average inefficiency is not sensitive to the econometric specification, the efficiency ranking varies significantly across models. The reasonably low out-of-sample prediction errors suggest that panel data models can be used as a prediction instrument in order to narrow the information gap between the regulator and regulated companies.

Fuel choices in urban Indian households

This paper applies an ordered discrete choice framework to model fuel choices and patterns of cooking fuel use in urban Indian households. The choices considered are for three main cooking fuels: firewood, kerosene, and LPG (liquid petroleum gas). The models, estimated using a large microeconomic dataset, show a reasonably good performance in the prediction of households’ primary and secondary fuel choices. This suggests that ordered models can be used to analyze multiple fuel use patterns in the Indian context. The results show that lack of sufficient income is one of the main factors that retard households from using cleaner fuels, which usually also require the purchase of relatively expensive equipments. The results also indicate that households are sensitive to LPG prices. In addition to income and price, several socio-demographic factors such as education and sex of the head of the household are also found to be important in determining household fuel choice.

Unobserved heterogeneity in stochastic cost frontier models: an application to Swiss nursing homes

This paper applies a number of stochastic cost frontier models to a panel data set and compares their ability to distinguish unobserved heterogeneity from inefficiency variation among firms. The main focus is on Greenes 2005 panel data model that incorporates firm-specific effects in a stochastic frontier framework. In cases where the unobserved heterogeneity is correlated with explanatory variables, while the random effects estimators can be biased the fixed effects model may overestimate inefficiency. In line with Mundlak, a simple method is proposed to include such correlations in random effects specification. The sample includes 36 Swiss nursing homes operating from 1993 to 2001. The results suggest that the proposed specification can avoid the inconsistency problem while keeping the inefficiency estimates unaffected.

Application of Panel Data Models in Benchmarking Analysis of the Electricity Distribution Sector

This paper explores the application of several panel data models in measuring productive efficiency of the electricity distribution sector. Stochastic Frontier Analysis has been used to estimate the cost-efficiency of 59 distribution utilities operating over a nine-year period in Switzerland. The estimated coefficients and inefficiency scores are compared across three different panel data models. The results indicate that individual efficiency estimates are sensitive to the econometric specification of unobserved firm-specific heterogeneity. When these factors are considered as a separate stochastic term, the efficiency estimates are substantially higher indicating that conventional models could confound efficiency differences with other unobserved variations among companies. The results suggest that alternative panel models such as the “true” random effects model proposed by Greene (2005) could be used to evaluate the possible impacts of unobserved factors such as network effects on efficiency estimates.

Changes in Hospital Quality after Conversion in Ownership Status

This paper examines the effects of conversions between For-Profit and Not-For-Profit forms on quality of medical care in California hospitals. The sample includes elderly patients treated in Californias private hospitals from 1990 to 1998 for Acute Myocardial Infarction and Congestive Heart Failure. The results suggest that converted hospitals have experienced quality changes before conversion and that ignoring these changes may bias the estimates of conversion effects. Both conversions are found to have some adverse consequences: Hospitals that converted to FP form show an increase in AMI mortality rates, while those converted to NFP status indicate an increase in CHF mortality outcomes.

Context effects and heterogeneity in voluntary carbon offsetting – a choice experiment in Switzerland

Voluntary carbon offsets allow individuals to neutralise the CO emissions from their consumption. In a choice experiment among more than a thousand Swiss consumers, we analyse how the propensity to offset varies with consumption contexts and offset project attributes. The adopted latent class model accounts for heterogeneity in consumers’ preferences and in their motivations to buy carbon offsets. We find that consumers are not only responsive to project type and quality aspects – such as government certification – but also to the consumption context. Our results suggest that carbon offsets are perceived as differentiated rather than homogeneous goods. Estimating a single willingness to pay measure for offsets, as previous studies have done, may thus be misleading. To complement our analysis, we provide a characterisation of offset customers as well as insights into the relationship between carbon offsetting and other voluntary mitigation behaviour.

Advances in understanding energy consumption behavior and the governance of its change : outline of an integrated framework

Transforming today’s energy systems in industrialized countries requires a substantial reduction of the total energy consumption at the individual level. Selected instruments have been found to be effective in changing people’s behavior in single domains. However, the so far weak success story on reducing overall energy consumption indicates that our understanding of the determining factors of individual energy consumption as well as of its change is far from being conclusive. Among others, the scientific state of the art is dominated by analyzing single domains of consumption and by neglecting embodied energy. It also displays strong disciplinary splits and the literature often fails to distinguish between explaining behavior and explaining change of behavior. Moreover, there are knowledge gaps regarding the legitimacy and effectiveness of the governance of individual consumption behavior and its change. Against this backdrop, the aim of this paper is to establish an integrated interdisciplinary framework that offers a systematic basis for linking the different aspects in research on energy related consumption behavior, thus paving the way for establishing a better evidence base to inform societal actions. The framework connects the three relevant analytical aspects of the topic in question: (1) It systematically and conceptually frames the objects, i.e. the energy consumption behavior and its change (explananda); (2) it structures the factors that potentially explain the energy consumption behavior and its change (explanantia); (3) it provides a differentiated understanding of change inducing interventions in terms of governance. Based on the existing states of the art approaches from different disciplines within the social sciences the proposed framework is supposed to guide interdisciplinary empirical research.

Retail demand for voluntary carbon offsets – a choice experiment among Swiss consumers

Using a choice experiment conducted among more than a thousand Swiss consumers, we analyze the individual demand for voluntary carbon offsets in different contexts. The analysis is used to identify the consumers’ underlying motives for offsetting emissions, the context effects on their willingness to pay and the influence of the offsetting project characteristics on their propensity for contribution. Furthermore, the characteristics of potential buyers as well as the possibilities of behavioral rebound are explored. To support our results, we assess whether the hypothetical preferences are consistent with the revealed behavior. The adopted latent class model accounts for heterogeneity of preferences with respect to offset products offered in the market. The results provide a quantitative assessment of consumers’ marginal valuation of carbon offsets and a better understanding of individual preferences. The results also point to strong heterogeneity among individuals favoring targeted policy measures to induce voluntary contribution.

Economies of scale and efficiency measurement in Switzerland's Nursing homes

SummaryThis paper examines the cost efficiency in the nursing home industry, an issue of concern to Swiss policy makers because of the explosive growth of national expenditure on elderly care and the aging of the population. A stochastic cost frontier model has been applied to a panel of 1780 observations from 356 nursing homes operating over 1998–2002 in Switzerland. We compare the estimation results from different econometric techniques focusing on the specification of unobserved heterogeneity across firms. The potential effects of such unobserved factors on the estimation results and their interpretation have been discussed. The findings suggest that the economies of scale are an important potential source of cost reduction in a majority of Swiss nursing homes. Moreover the average performance of a representative nursing home is very close to the estimated best practice.

The economies of scale in the French power distribution utilities

The aim of this study is to provide some empirical evidence in support of the ongoing re-structuring initiated in 2005, toward re-grouping certain activities across several distribution units, by exploring the cost structure of the electricity distribution units operating in France over the three year period between 2003 and 2005. The sample includes 279 observations from 93 distribution units operating within the French electricity distribution network ERDF. A Cobb-Douglas cost function is estimated using several specifications focusing on the analysis of the economies of scale and customer density. In order to account for the unobserved heterogeneity and its impacts on the economies of scale, we use a latent class specification. The results suggest that a majority of the distribution units can exploit statistically significant economies of scale. Further, the empirical analysis indicates that the unexploited economies of scale can vary considerably from one unit to another, not only because of variations in outputs but also because of the unobserved differences in networks and technological characteristics. In particular, the latent class approach can identify a group of distribution units that do not show any significant economies of scale. Further analysis suggests that such distributors are often located in metropolitan areas with high customer density.