In this chapter, we provide an overview of research on neighborhoods and social networks and their role in shaping behavior and economic outcomes. We include a discussion of empirical and theoretical analyses of the role of neighborhoods and social networks in crime, education, and labor-market...

We consider a model where each individual (or ethnic minority) is embedded in a network of relation-ships and decides whether or not she wants to be assimilated to the majority norm. Each individual wants her behavior to agree with her personal ideal action or norm but also wants her behavior to...

This paper surveys some of the strategic aspects that emerge if players fight in an alliance against an enemy. The survey includes the free-rider problem and the hold-up problem that emerges in the baseline model, the role of supermodularity in alliance members' effort contributions, the role of...

We study peer effects in crime by analyzing co-offending networks. We first provide a credible estimate of peer effects in these networks equal to 0.17. This estimate implies a social multiplier of 1.2 for those individuals linked to only one co-offender and a social multiplier of 2 for those...