bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficacité dans la production céréalière : une approche non paramétrique
Authors: Perrigne Isabelle , Simioni Michel 
Published: March 2022

La détermination de la taille minimale efficace d'une unité de production joue un rôle crucial dans l'étude de la concentration d'un secteur productif. Cet article propose d'utiliser le cadre d'analyse développé par Baumol, Panzar et Willig (1982), en vue de mesurer, via l'estimation des économies d'échelle, la taille minimale efficace d'une telle unité. Le recouvrement des économies d'échelle y est réalisé en utilisant la technique non paramétrique appelée méthode du noyau de convolution afin d'estimer une fonction de coût multiproduit et ses dérivées partielles par rapport aux prix des inputs.
Cette approche est illustrée à partir d'un échantillon d'exploitations céréalières françaises en 1986. Celles-ci sont ainsi en majorité caractérisées par des économies d'échelle croissantes. Ce résultat suggère qu'en moyenne, ces exploitations ont une taille insuffisante. De plus, leur nombre apparaît trop élevé par rapport à celui correspondant à une structure efficace du secteur pour la production totale observée. Ces résultats semblent corroborer la tendance observée vers une plus grande concentration dans la production céréalière.
Short and long-run elasticities of nitrogen demand : an application of cointegration to Italian data
Authors: Tiezzi Silvia 
Published: March 2022

Nous nous efforçons d'évaluer l'élasticité prix de la demande d'azote minéral en Emilie-Romagne, l'une des régions les plus touchées par l'eutrophisation des eaux. Il est important de savoir, pour des besoins de politique économique, si la demande d'engrais est élastique par rapport à son prix, lorsque l'on souhaite réduire la consommation d'intrants polluants. Or, les auteurs ne sont pas d'accord sur le niveau de l'élasticité prix de la demande d'azote. Nous utilisons un modèle dynamique à une équation, sous contrainte de maximisation du profit, où la demande optimale d'azote dépend de son prix, des prix escomptés à la production et des surfaces occupées. Les modèles dynamiques à une équation sont utilisés depuis longtemps pour mesurer la demande d'engrais, la relation d'équilibre étant associée à une hypothèse d'ajustement partiel. Afin d'éviter les problèmes afférents à cette hypothèse, nous estimons les paramètres d'équilibre à l'aide d'un modèle à correction d'erreurs (ECM). Pour cela, il est indispensable que les variables utilisées soient cointégrées. Nous vérifions la cointégration de deux façons : en utilisant les régressions statiques d'Engle-Granger ou la méthode du maximum de vraisemblance mise au point par Johansen.
Avec ce modèle à correction d'erreur :
1) l'ajustement à une situation d'équilibre de court terme est d'environ 29% par an ;
2) l'élasticité prix de la demande d'azote est de -0,87 à court terme, et de -1,82 à l'équilibre ;
3) une hausse de 2% du prix réel de l'engrais conduirait à faire baisser sa demande de 1,6% à court terme et de 3,8% à long terme 4) une réduction prolongée des surfaces utilisées aboutit à réduire la consommation d'azote à long terme, même si l'élasticité par rapport aux facteurs fixes est nettement inférieure à 1. En simulant la mise en vigueur d'une taxe verte, nous montrons que la consommation d'azote a des chances d'être considérablement réduite quand on augmente son prix de 10 à 20%. Nous constatons aussi que le recours à une taxe peu élevée, mais sur une longue période, a plus d'incidence sur la consommation d'azote qu'une taxe plus élevée. Cela signifierait donc qu'une évolution de la technologie peut être induite par une hausse prolongée des prix.
Nouvelles estimations des pertes de bien-être et de surplus du consommateur dans l'industrie agro-alimentaire américaine
Authors: Connor John M. , Peterson Everett B. 
Published: March 2022

Arnold Harberger, in a seminal 1954 paper, was the first to estimate empirically the deadweight social losses due to imperfect competition. By imposing five key assumptions (linear demand, unit price-elasticity, effective cartel pricing, constant marginal costs, and competitive profits = average profits), he concluded that US welfare losses were insignificant. In the past 15 years, advances in oligopoly theory have produced new algorithms that permit the calculation of economic losses and that relax some Harberger' s restrictive assumptions. Having accurate estimates of interindustry losses is important for the enforcement of competition laws.
This paper examines the sensivity of economic losses due to market power across different oligopoly models with a variety of parametric values, data sources, and time periods. The alternative structural models include monopoly pricing, Cournot pricing with homogeneous or heterogeneous products, various forms of price leaderships, and general industry-wide oligopoly pricing. Own-price demand or supply elasticities may be fixed or may vary accross industries. All the estimates examined in this paper utilise US Census Bureau concentration indexes for the food manufacturing for various years between 1967 and 1987. Most estimates rely on Census price-cost margins , while others calculate price ratios from commercial micro-data sets. Finally, most estimates adopt perfect competition as the measurement criterion, whereas others prefer «workable»
In view of these many differences in estimation methods, it is not surprising that average economic losses due to market power range widely. As expected from theory, the deadweight welfare losses are higher under monopoly pricing and under Cournot pricing ; average losses are greater when de¬ mand is convex to origin that when it is linear ; and consumer income transfers are about 40 times higher than the deadweight welfare losses. Somewhat surprising are the implausably high welfare losses when price leadership among the top four firms is assumed (equilibrium prices are frequently infinite), but we suspect the losses would be lower if the demand or supply elasticities were higher.
We further analyzed the cross-industry correlations of the alternative loss estimates. We find that cardinal estimates vary substantially, but ordinal results very little. Thus, from the point of view of the enforcement of competition laws, the theoretical and empirical progress of the past 15 years has done little to alter the rank of the principal target industries. While the positive correlations among economic-loss estimates is comforting, much work remains to be done to improve estimation techniques and to decide rationally which behavorial models are correct.
Formation et répartition des gains de productivité dans l'agriculture française. Analyse par produit
Authors: Butault Jean-Pierre , Delame Nathalie , Rousselle Jean-Marc 
Published: March 2022

Productivity increases in some French agricultural sectors and their distribution.
A lot of studies concern the measurement of the productivity growth of the whole agricultural sector. These analyses are often limited because the evolution of the conditions of production are very different according to the products. This paper aims at analysing the generation and the distribution of productivity increases in some French agricultural sectors (soft wheat, corn , greenhouse vegetables, fruits, cattle, sheep, milk, pig, and poultries ), between 1979 and 1991. First, a simple econometric model is used to build the different products accounts, from the French RICA (FADN). Then, volumes, prices and productivity indexes are calculated for these products and the surplus accounting method is applied to study how the productivity increases are distributed.
The results show that the conditions of the generation and distribution of productivity increases are very different according to the sectors. In the cereals sector, the productivity increases are very important : for the wheat, the rate of labour productivity is 6 % per year and the total rate of productivity 3 % per year. This productivity surplus is completely absorbed by the fall in prices, benefitting to customers of the cereal sector. It induces a great contribution in the surplus accounting of the animal sector : for example, the fall of prices of the intermediate consumptions represents, in the milk and pig sectors, half of the whole distributed surplus. In some animal sectors (cattle , for example ). the productivity increases are low but the costs of production fall, following the drop of prices of the intermediate consumptions. One of the interest of the surplus accounting method consists in allowing to study these relations between the different sectors and it may be used to follow the effects of the CAP reform.
Migrations ville-campagne et chômage : un test d'interdépendance
Authors: Tahar Gabriel 
Published: March 2022

A test of interdependence between urban-rural migrations and unemployment.
A considerable amount of migrations appears to be economically motivated. The behavior of individuals at the micro level is not only an expression of preferences but reflects their situations vis-a-vis the labor market. In particular, the problem of correlation between unemployment and migration is always raised but it is often evacuated by lack of suitable data.
We present here a straightforward statistical method, relied on multivariate counting processes theory, which allows to study the interdependence between two couples of states : to be or not to be unemployed, to reside in an urban or a rural area. We use an adapted test procedure which compares two "parallel" transitions intensities to point out significative differences between the couples of transitions and then to detect the interaction between participation and migration processes. In an application to data from the INSEE Training-Professionnal Qualification survey of 1985, we find that the urban or rural localization affects heavily the probability of falling unemployed with a significantly higher "risk" in town. On the opposite, the exit from unemployment does not depend on the localization. We improve the accuracy of our results by splitting our sample into respectively men or women and young or older people, as the various transitions are very inequally distributed among ages and sexes.
Frontière de production et données de panel : application aux exploitations céréalières
Authors: Perrigne Isabelle 
Published: March 2022

Production frontier and panel data : application to grain farmers.
This paper deals with the issue of estimating a stochastic production frontier and of measuring technical efficiency from a complete panel of grain farmer from 1982 to 1986.
A survey of classical panel data econometric methods (Within and GLS) and their applications underline the limits of their use with respect to the empirical results and the characteristics of our data set. Moreover, the Hausman test shows a correlation between inputs and the error term which represents inefficiency, which invalidates GLS estimation. The use of a new method proposed by Ivaldi, Perrigne and Simioni (1994) based on a co-variance structural analysis allows to reveal correlations between regressors and the individual effect as well as to estimate an individual time-varying technical efficiency. Empirical evidences show a negative correlation between materials and efficiency and a declining trend for efficiency between 1982 and 1986.
Economie de la perception et qualité des produits. L'exemple des contrefaçons dans le domaine agro-alimentaire
Authors: Bessy Christian , Chateauraynaud Francis 
Published: March 2022

Perception and product quality as exemplified by counterfeit products in the food industry.
Many contemporary developments have focused on the way in which the quality of food industry products is engineered. Analysis in terms of quality conventions allows us to formalise the processes by which series of product characteristics with set definitions are formed. A lthough the conventional aspect of a product's properties serves to limit uncertainty about the behaviour of agents, it does not always explicitly include the terms of their attachment, i.e. the conditions by which agents can grasp the actual substance of products in the course of a learning process and on which evaluation indicators can be based. Counterfeiters of food industry products slip into this conventional economy through the gap, which is more-or-less wide depending on the setup, between representations and perceptual abilities. Using the issue of perception and memory as a point of entry, the idea is to enquire into these modes of learning and of acquiring expert evaluation skills. An attempt has been made to supplement the examination of rules and conventions by perception economics, meaning the different ways of drawing on sensations in a perceptual system that leads from sensations to judgments, from corporeal tests to representations.
The significance of the authentification tests that we have analysed comes out clearty : it is a matter of underwriting evaluation and judgement by returning to the primary experiences that are used to test both the skills of agents and to try out the soundness of products that serve as bench marks or standards -even if this means converting them in a negotiated manner if they no longer manage to make the transition between sensations and collective representations. By varying the situations, we have insisted here on showing that such tests were conducted not only with reference to a legal framework (patent infringement suits or approval or certification procedures ) involving acknowledged experts, but also in the course of everyday life whenever we had misgivings about a food product. Such empirical variation can be used to accurately describe the constraints weighing on the learning process and to provide a definition of tacit knowledge.
L'affectation du travail dans les exploitations agricoles : une application du modèle du ménage producteur et consommateur
Authors: Benjamin Catherine 
Published: March 2022

Labour allocation on the farm : an application of the agricultural household model
This paper is based on the neo-classical farm-household model. The aim is to show how this theoretical framework allows to characterize all the labour decisions of the farm household : the decision to use hired labour on farm and the decision to work off farm. Indeed, these decisions are joint and the model takes into account their simultaneity. An important feature of the analysis arises from the fact that we consider the labour market might be imperfect : hence, the cost of hired labour can be different from the off-farm wage rate. The farm household is defined as an economic entity and is assumed to maximise its utility function subject to income, time and non-negativity constraints. On-farm and off-farm family labour are assumed to be perfect substitutes in the utility function as well as family labour and hired labour in the production function despite their differential opportunity costs. The farm household model characterizes the rule for off-farm participation : the household will not work off farm when its marginal value of time from not participating in the off-farm labour market (its reservation wage) is greater than the wage rate offered off-farm. Hired labour is used on farm when the marginal value of hired labour equals its cost. Rational choice by agricultural households lead them to choose differential labour strategies and thus to belong to different labour regimes. The reduced form of the model defines six labour regimes depending on the value of the labour variables. The model is illustrated with the use of functional forms (Cobb-Douglas forms) for the utility and the production functions. This example allows to derive the different regimes and to point out on the case when the production decisions depend on the preferences of the household i.e. when the recurs ivity of the household behaviour does not hold. Furthermore the impact of the new Common Agricultural Policy on the labour decisions of the farm-household is studied. The comparative static of the reservation wage with respect to the instruments used in the new CAP regime allow the formation of hypotheses regarding how CAP will affect labour decisions.
Efficacité privée et publique de la gestion du risque phytosanitaire : le rôle de l'information
Authors: Carpentier Alain 
Published: March 2022

The analysis of farmers' phytosanitary information use requires the specification of information as an input that is produced and used on the farm. The information input is assumed to consist in a signal that is correlated with (future) pest infestation of the farmers' fields. This signal is received by farmers before they choose their pest applications. The quality of information is measured by the accuracy of the signal in predicting the actual infestation. Using this approach it is easily shown that farmers' attitude toward risk, information quality and pesticide application costs play crucial roles in farmers' crop protection decisions.
In order to study farmers' information use decisions we also consider the production cost of this input for farmers. Within this framework, although they appear inefficient from a public standpoint, it is assumed that systematic pesticide applications may be chosen by economically efficient farmers. Showing that the information production cost is likely to be high for a large part of French farmers' population we conclude that this cost is likely to be one of the most determinant factor explaining the current use of systematic pesticide applications by French farmers.
Despite their weaknesses, the models developed in this paper provide some guidelines for pesticide use reduction policy design. Within the current European economic context, the use of information relative to pest infestation should result in a decrease in farmers' pesticide uses. This result is, to a large extent, supported by the fact that pesticides appear relatively cheap. As a consequence, the implementation of instruments aimed at the promotion of the use of phytosanitary information could be used as a policy intended to decrease farmers' pesticide applications. However, the promotion of information use can only be viewed as a medium or long term policy. Infortnation use by farmers requires adjustments in quasi-fixed factors (human capital, labour) and/or structural adjustments (creations of public or private firms producing expertise services). It is also shown that farmers' willingness to pay for phytosanitary information is an increasing function of pest application costs. This result implies that farmers' pesticide demand elasticity could be important (in absolute value) in the long run, i.e. due to adjustments in information uses. It also implies that a tax on the price of pesticide would strengthen the effects of policies aimed at reducing the information production costs for farmers.
L'évaluation contingente : controverses et perspectives
Authors: Amigues Jean-Pierre , Desaigues Brigitte , Vuong Quang H. 
Published: March 2022

Contingent valuation : controversial issues and perspectives
In recent years, increasing public awareness of the detrimental effects of the economy on the environment has forced policymakers to assess the value of various public goods such as clean air and water, plant and animal species preservation, recreational sites and activities, scenic beauties, etc....
Over the last two decades, economists have developed and applied the method of contingent valuation to measure the value of various public goods. Recently a debate has raised among economists about the validity and rationality of the method. This debate pointed out some difficulties of contingent valuation studies. Measurement of the so called non use or preservation values has proved difficult. People may be sensitive to the warm-glow effect, and their answers may reflect more their willingness to pay for the environment in general than for the environmental good they are asked to value. Various solutions have been proposed to deal with these problems. We present and discuss them and we analyse the prominent elements of the current debate around the contingent valuation method. We develop the idea that currently used referendum methods have a too poor information content to provide reliable answers when the value of the good exhibits an important non use value component. We then explore the conjecture that the lack of imitations in the procedure may be a cause of unreliability of answers in contingent studies. Going back to the auction tradition of contingent valuation, we propose alternative ways of resolving some of the difficulties encountered in the practice of contingent valuation studies.
Nouvelle PAC et nouveaux projets d'irrigation
Authors: Cohen Juliette , Dupraz Pierre , Vermersch Dominique 
Published: March 2022

New CAP and investments in irrigation facilities
In France, there is an increasing trend in irrigated land, especially where there are cereal and oil seed crops. In connection with the reform of the Common Agricultural Policy, major changes have affected irrigating farmers. This reform combines a decrease in farm prices with compensatory direct payments and a land set-aside scheme (restricted to professional farm operators). The implementation of the scheme takes into account regional diversity since payments are based on a flat rate per hectare which is determined using a reference yield for each "départements". Besides, special reference yields concerning irrigated crops are set apart in 55 "départements" to reflect the higher yields of irrigated land. Nevertheless there is an upper limit for this compensation, since only land equipped with irrigation facilities by 1992, is considered. The potential behaviour of a representative farmer facing this scheme is derived from a single microeconomic model. There is some evidence that it would not be profitable to develop facilities in order to irrigate more land. This conclusion holds for a drop in price as well as for the upper limit of total subsidy. It is questionable where there is a significant difference between reference and actual yields. A dramatic increase in world prices similar with the increase of 1995 could make profitable investing in irrigation facilities.
This scheme involves a top premium part on water input which benefits irrigating farmers. They are entitled with property rights over water resources which are revealed through the payment scheme. Farmers' rights may prevail upon the rights of other categories of water users. This distribution of property rights does not reflect the social value of water in its alternative uses. Thus the CAP reform leads to paying pecuniary externalities, and results in a monetary transfer which benefits intensive cropping systems. This scheme does not benefit low input farming which creates amenities. Such a mechanism supports farm concentration, cost-competitive farming systems while environmental friendly practices are not encouraged.