Integration and segregation of immigrants in the labor market.

Summary The issues related to the integration of immigrants in host countries are positioned in an international context characterized by an increase in population flows over the last few decades. The mechanisms identified as determining the integration of immigrants in the labor market depend on individual, social and economic characteristics. Based on this observation, we analyze in this thesis the role of social relations as a determinant influencing both the integration of immigrants into the labor market and the professional mismatch of immigrants. Concerning the role of social networks as a means of job search, we analyze, using French data, the relationship between the network effect and the business cycle. Our results show that the network effect is countercyclical. The mobilization of intermediaries to find a job is stronger in periods of economic recession than in periods of economic growth. We extend our analysis by studying the relationship between occupational mismatch and the network effect. Beyond individual characteristics that may help explain the probability of being over/undereducated, we hypothesize that finding a job through an intermediary influences the educational match between immigrants and the jobs they hold. We find an ambiguous effect between the role of intermediaries and occupational mismatch by immigrant origin.