Contenu du sommaire : Etudes sectorielles

The taxation of oil products : an economic analysis, by Patrick Bœuf, Zoé Formery. This paper deals with the taxation of oil products. The analysis is twofold. We first consider that such a taxation regulates the demand of highly imported products ; secondly, that it is a way to internalyze externalities, especially road users' ones. We give some quantitative estimations which are compared with current tax levels.

Redistribution effects and efficiency gain of a program reform of tenants' aid in France, by Véronique Nichèle. The effects of the reform in this aid program on the welfare of tenants are analysed on the basis of the survey : « Households' Budgets in 1979 », carried on by the Inséé. King's methodology (1983) is applied to an expenditure system resulting from a translog indirect utility function which needs the computation of individual prices for housing. The consequences of the reform. ( welfare variation, horizontal and vertical inequality ) are evaluated. The study indicates that poor households or households without children benefit from the reform.

Tentative estimates of qualitative factors of productivity, by Jacques Mairesse, Mohamed Sassenou. Besides taking into account the two main production factors, i.e. capital and labour as usually measured, the present study is an attempt to assess the influence of some qualitative factors explaining the productivity of firms : the age of equipment, the labour force's qualification, the importance of their internal R-D capital stock and the R-D capital intensity of the industry. The estimates are performed on a cross section of about three hundred manufacturing firms ; in spite of specification and measurement problems, they seem satisfactory, being both statistically significant and of a reasonable order of magnitude.

Production factor demand and long-term productivity : the contribution of the quasi-fixed capital production function, by Jean-Guy Devezeaux de Lavergne, Norbert Ladoux. The fixed or quasi-fixed capital functions allow us to distinguish the short run from long run behaviour of the producer, which is not the case in the classical functions. The main contribution of this paper is the explicit calculation of the long run elasticities of substitution. As an empirical application, we estimate a translog quasi-fixed capital function for three sectors of the french economy. Our results show that it is impossible to consider, as it is sometimes done, that the elasticities computed through classical cost functions (in particular the capital-energy elasticity) are long run elasticities. In addition, we give an estimate of the utilization rate of the production capacity, as well as an estimate of the total factors productivity (which are not very different from that obtained when the capital stock is optimal). We also furnish an evaluation of productivity trends affecting each productive factor. Our results include the levels of significance of each computed variable.

Distribution of work in grain producing farms : a Tobit model of semi-fixed labour, by Dominique Vermersch. Conventional models derived from duality theory assume that labour is either a fixed factor or a variable one. In this paper, we examine a more realistic model which uses the Tobit approach. Labour is assumed to be semi-fixed : it is free to vary for some observations and it is fixed for the others. The fast part is devoted to the estimation of this model using a cross-section of farms.

Estimates of production frontier and technical inefficiency in a cross-section of tunisian companies, by Mohamed El Arbi Chaffai. This paper summarizes the methods used to estimate parametric production frontiers and the technical inefficiency of firms. A stochastic production frontier based on a cross-section of 385 companies is estimated for six industrial sectors of the tunisian economy. The translog specification is more significant than the Cobb-Douglas one, and the degree of technical inefficiency in the sectors examined ranges from 24 % to 37 %.

The energy demands in dairy industries : a micro-economic analysis, by Alain Bousquet, Marc Ivaldi, Norbert Ladoux. An empirical analysis examines substitution opportunities for various forms of energy in the dairy industry. First, we estimate a demand function system for energy factors in order to grasp their substituability. It is then possible to understand the trends in the structure of the energy consumption. Zero expenditures in the sample require a special treatment when the model is specified. And this is true for two different stages : the theoretical one as well as the econometric one. The model is similar to qualitative variable models such as the general Tobit model.

An instrument of measurement for agricultural support, by Jean-Jacques Berger. Multilateral negotiations require a common frame of values and instruments in order to measure and control mutual concessions. This paper discusses the main features and the limits of such an approach in the case of the Uruguay-Round.

The reforms in Common Agricultural Policy : economical assessment and perspectives for France, by Xavier Delache, Michel Deroin-Thevenin. Substantial reforms in the Common Agricultural Policy have been achieved since 1984. During these reforms, two alternative guidelines were in balance : — either a decrease in price support, allowing a more efficient resource re-allocation, leading to important productivity gains benefiting the consumer ; — or a supply control in favour of producers' revenue with a direct effect on public expenditures, but threatening efficiency and competitiveness. This paper presents an evaluation of the reforms undertaken and of their consequences.

Example of an application of the Logit model : home ownership by unmarried couples, by Claire Sarma. Unmarried couples own their own dwelling less frequently than the married ones. This paper discusses the usefulness of the Logit model in isolating the specific influence of marital status — and age — on home ownership. The study is based on a sample of 5 600 households.

The reorganization of civil aviation in the United States and in Europe, by Patrick Bœuf. This paper provides a broad overview of the civil aviation deregulation process in the United-States and in Europe. The first part deals with the recent deregulation in the United States as it can be analysed from an economic standpoint. The second part raises the question of how far Europe would benefit from similar reorganization.

Problems arising in the Logit approach : an example from the transportation economy, by Pascal Bouyaux. This article presents a survey of the traditional foundations and interpretations of a Logit approach, applied to the urban travel demand modelling. Using the notion of stochastic rationality introduced by Falmagne (1978), it formalises the theoretical framework from which McFadden (1974) derived the Logit model with the maximisation of a random utility function. This framework, corresponding solely to the modelling of preferences heterogeneousness of a population, is too limited because it doesn't take into account the non-repeated character of the travellers choice's process. Therefore, an alternative model is proposed, originally elaborated by Beggs, Cardell and Hausman (1981) : the ordered Logit model. Beyond the preferences' heterogeneousness, this new approach allows to give back to the urban travel demand modelling all his behavioral character.