Diagnostic de l'efficacité productive par la méthode DEA. Application à des élevages porcins

Résumé En Fr

The measure of productive efficiency of firms interests not only economists but also management specialists who want to make a pertinent diagnosis of the decision making units they manage or advice. The general idea of estimation of efficiency is the following : the efficiency of a production unit is characterized by the distance between the observed production level and the maximal atttainable level of outputs that could be reached by the same unit in case of optimal use of its inputs. This optimal use is defined relatively to the analyzed sample of productive units. In the literature, many parametric and non parametric methods have been developed. In this article, we adopt a specific non parametric method for measuring the productive efficiency (data envelopment analysis method proposed by Charnes, Cooper and Rhodes, 1978) and we show its capacity of establishing an operational diagnosis of firms performance. In such an approach, no functional form is assumed concerning the relationship between the inputs and the outputs and all the distance between the observed data and the production frontier measures the inefficiency. Based on linear programming giving easier interpretation than the econometric methods, DEA establishes a technical and scale efficiencies diagnosis for each decision making unit. The factors savings can be quantified and the origin of the inefficiency can be classified between bad scale of the production and ! or bad use of the inputs. Then the long-run optimal level of activities (most productive scale size) can be calculated. From an application on 62 pig breadings, using data from ITP 's survey (Institut technique du porc) the coherence of the DEA evaluation with the analysis of the usual technical and financial ratios is demonstrated. Our study shows that a simple specification of the production function (one output and six inputs) is able to carry the same information than usual technical and financial ratios but that final diagnosis is built on the best and not on the average practices of the sample. Furthermore, the diagnosis made by DEA tends to respect the production process of the evaluated units.

La mesure de la performance productive des firmes intéresse non seulement les économistes mais aussi les praticiens de la gestion qui souhaitent dresser un diagnostic pertinent des entreprises qu'ils conseillent ou dirigent. Dans cette perspective, cet article présente une méthode de mesure de l'efficacité productive (méthode DEA) et démontre sa capacité à établir un diagnostic opérationnel de performance des entreprises. A partir d'une application sur 62 élevages porcins, il révèle la cohérence du diagnostic DEA avec les démarches usuelles d'analyse de ratios techniques et financiers et la pertinence des informations nouvelles générées.