Incertitude, concentration industrielle et relation structure-performance
Institution:
CaenDisciplines:
Directors:
Abstract EN:
The main target of this thesis is to propose, in term of demand uncertainty, an explanation of the increasing role played by the small firms in the industry since the seventries and of the structure-performance relation deterioration abserved in the empirical studies during the same period. The first part introduces the competitive models used to show random demand effect on the industrial concentration. The eventual diversity ( the coexistence of firms different efficiency) arises from the technological choice of the firms, and the uncertainty promotes the smaller firms which are supposed to be more flexible than the larger ones. The second part introduces some models with dominant firms and competitive fringe. The eventual industrial diversity results then from the strategy selected by the larger firms (the dominant firms). Moreover, we show how the uncertainty is able to spoil the structure-performance relation. Finally, the empirical part first, tests the influence of uncertainty on industrial concentration and on the subcontracting degree, and second, shows that the structureperformance relation deterioration results from the industries characterized by a high degree of uncertainty.
Abstract FR:
L'objectif principal de cette these est de proposer une explication en terme d'incertitude de la demande, d'une part, de la participation croissante des petites firms a l'activite economique depuis le milieu des annees soixante-dix et, d'autre part, de l'alteration de la relation structures-performance observee dans les etudes empiriques depuis cette meme epoque. La premiere partie presente des modeles concurrentiels destines a degager l'influence de l'incertitude de la demande sur la concentration industrielle. La diversite eventuelle de l'industrie (la coexistence de firmes difference) provient alors de l'hypothese de choix de technologie par les firmes et l'incertitude favorise les petites firmes (supposees plus flexibles que les grandes). La seconde partie presente des modeles de marches a firmes dominantes et frange concurrentielle. La diversite eventuelle de l'industrie est alors due a la strategie des grandes firmes (dominantes) vis-a-vis de leurs rivales concurrentielles. De plus, on montre comment l'incertitude altere la relation concentration-performance. Enfin, la troisiele partie, empirique, d'une part, teste l'influence de l'incertitude sur la concentration et le taux de sous-traitance (suppose refleter une recherche de flexibilite externe de la part des grandes firmes) et, d'autre part, montre que l'alteration de la relation sturcture-performance est due aux industries a forte incertitude.