Equilibrium job search models.

Summary This thesis is a contribution to the study of equilibrium job search models. It is composed of three chapters. The first one is devoted to a review of the literature on the subject, the next two present the models we have developed which incorporate features already present in the first models of this kind. In particular, they allow an employee to make job-to-job transitions. Two forms of heterogeneity are considered: firm and worker heterogeneity. Chapter II considers only the case of heterogeneous firms while the last chapter considers both forms of heterogeneity in the same market. The equilibrium of the economy is analyzed in detail. It is shown that, when the distribution of firm productivity is continuous, there is a bijective relationship between the wage offered by a firm and labor productivity. Particular attention is paid to the properties of the equilibrium wage distributions induced by these models. Indeed, one of the drawbacks of the previously developed models is to generate a cross-sectional wage distribution that is incompatible with the observed distributions. We show that firm heterogeneity is necessary to obtain a good fit. Other qualitative results concern the influence of the shape of the tails of the productivity distribution on those of the wages offered. Finally, we take into account the introduction of a legal minimum wage and derive necessary and sufficient conditions for the wage distribution to peak at this minimum wage. We develop multi-stage semi-parametric structural estimation methods of these models, based on an inversion of the wage-productivity function. We use these methods to estimate these models on French data from the INSEE employment survey.