FONTAINE Francois

The objective of this thesis is to study the contractual dualism existing in the French labor market.I am interested in the flows taking place in the French labor market by highlighting the importance of fixed-term contracts in these flows.French employment protection legislation seems a priori to be clear and concise and firms are subject to strict rules regarding the management of their labor force.However, it would seem that in practice, the constraints on firms in terms of the use of temporary contracts are not so clear and that the vision of the open-ended contract as a "normal" form of employment relationship is not so obvious for firms. Indeed, we observe that their use is very frequent and concerns jobs of increasingly short duration. The objective of this thesis is therefore to better understand the functioning of the French labor market and the impact of contractual dualism. To this end, this thesis is composed of three chapters. The first chapter assesses the magnitude of job and worker flows over the period 1998-2012 by highlighting the impact of the 2008 crisis on these flows as well as the potential strengthening of contractual dualism after this date.I take into account sectoral specificities by isolating the sectors authorized to use so-called contracts of use in order to study the behavior of firms in terms of hiring in these particular sectors.I also detail the evolution of these job and worker flows as a function of firm size. In addition, I study the evolution of the duration of fixed-term contracts over this same period. Finally, I implement an econometric model to shed light on the main determinants of fixed-term contract hiring. In the second chapter, I measure the state-to-state transitions taking place in the French labor market and their impact on the volatility of the unemployment rate. For this purpose, I use a three-state model (employed, unemployed, inactive) as well as a four-state model (permanent contract, fixed-term contract, unemployed, inactive) allowing to take into account the contractual dualism characterizing many European labor markets. This type of four-state model is a real novelty in the sense that it has never been implemented for France. Finally, the third article aims to analyze the consequences of the introduction of a tax on fixed-term contracts in order to encourage firms to hire more permanent employees and to increase the duration of contracts. This measure has recently been introduced in various forms in several European countries. For France, this tax was introduced by the National Interprofessional Agreement signed in 2013.To do so, a matching model is estimated on French data from UNEDIC relying on the model proposed by Cahuc, Charlot and Malherbet (2016).