A re-examination of the determinants of employment based on microeconomic data: the role of wage rigidities and factor substitution mechanisms.

Summary The objective of this thesis is to compare the behavioral models of the various actors in the labor market with individual data from firms and employees. More precisely, a new light on the structural determinants of employment is shed by estimating at the microeconomic level models of labor supply and demand. In the first part, the rent-sharing mechanism of firms is confirmed by estimating wage equations (chapter I and II), but it turns out to be small. The second part of the thesis studies the substitution mechanisms between factors of production. Chapter III first shows that an increase in the user cost of capital strongly degrades the profitability of firms and the scale of production. A more detailed analysis is conducted by disaggregating the labor factor into two categories of qualification (chapter IV). It confirms that skilled labor is relatively less substitutable for capital than low-skilled labor. Finally, the introduction of working hours would show that the hourly efficiency of employees would be little affected by a variation in hours worked (chapter V). The estimates of the various structural parameters will ultimately be used to calibrate a model of the labor market (chapter VII). The model, which is original compared to pre-existing disaggregated models (chapter VI), is an extension of the matching model, in the case where employees are heterogeneous from the point of view of qualification and can acquire specific human capital. The simulations show that shocks affecting the production function or the labor reallocation process could have a significant impact on the progression of structural unemployment, of a magnitude comparable to a possible shift in the wage curve.