We survey the literature on social networks by putting together the economics, sociological and physics/applied mathematics approaches, showing their similarities and differences. We expose, in particular, the two main ways of modeling network formation. While the physics/applied mathematics...

We show how small initial wealth differences between low skilled black and white workers can generate large differences in their labor-market outcomes. This even occurs in the absence of a taste for discrimination against blacks or exogenous differences in the distance to jobs. Because of the...

This paper explores a novel mechanism of gender identity formation. Specifically, we explore how the work behavior of a teenager's own mother, as well as that of her friends' mothers, affect her work decisions in adulthood. The first mechanism is commonly included in economic models. The second,...

This article consists in three parts. The first part deals with theory. We evaluate the pros and cons of government involvement in urban housing and of renting versus ownership. In the second part, we summarize the different housing policies that have been implemented in the United States,...

We develop a model where the unemployed workers in the city can find a job either directly or through weak or strong ties. We show that, in denser areas, individuals choose to interact with more people and meet more random encounters (weak ties) than in sparsely populated areas. We also...

This paper studies the role of strong versus weak ties in the rural-to-urban migration decision in China. We first develop a network model that puts forward the different roles of weak and strong ties in helping workers to migrate to the city. We then use a unique longitudinal data that allows...

We study the causal impact of network centrality on educational outcomes using field experiments in primary schools in Bangladesh. After obtaining information on friendship networks, we randomly allocate students into groups and give them individual and group assignments. We find that groups...

Using unique geo-coded information on the residential address of a representative sample of American adolescents and their friends, we revisit the importance of geographical proximity in shaping education outcomes. Our findings reveal no evidence of residential neighborhood effects. Social...

We study a structural model of R&D alliance networks in which firms jointly form R&D collaborations to lower their production costs while competing on the product market. We derive the Nash equilibrium of this game, provide a welfare analysis and determine the optimal R&D subsidy program that...

We develop a model where workers both choose their residential location (geographical space) and their social interactions (social space). In equilibrium, we show under which condition some individuals reside close to the job center while others live far away from it. Even though the two...