We examine peer effects in early education by estimating value added models with school fixed effects that control extensively for individual, family, peer, and teacher characteristics to account for the endogeneity of peer group formation. We find statistically significant and robust spillover...

This paper develops a model of social interactions with endogenous association. People are assumed to invest in relationships to maximize their utility. Even in a linear-in-means model, when associations are endogenous, the effect of macro-group composition on behavior is non-linear and varies...

Concerns over the perceived negative impacts of computers on social development among children are prevalent but largely uninformed by plausibly causal evidence. We provide the first test of this hypothesis using a large-scale randomized control experiment in which more than one thousand...

In the past decade, nearly 20 studies have found a strong, persistent pattern in surveys and behavioral experiments from over 40 countries: individual exposure to war violence tends to increase social cooperation at the local level, including community participation and prosocial behavior. Thus...

This paper provides a systematic analysis of identification in linear social interactions models. This is both a theoretical and an econometric exercise as the analysis is linked to a rigorously delineated model of interdependent decisions. We develop an incomplete information game that...

We examine the combined effects of popularity and feelings of being important to reaching a goal by testing how people react to situations in which their own behavior is pivotal or not, as well as the popularity of the action. We conduct a laboratory experiment to cleanly fix beliefs about the...

We study risky behavior of adolescents. Concentrating on smoking and alcohol use, we structurally estimate a dynamic social interaction model in the context of students' school networks included in the National Longitudinal Study of Adolescent Health (Add Health). The model allows for...

How do information interventions affect individual efforts to expand social networks? We study a randomized controlled trial of a program providing information on settling in the U.S. for new immigrants from the Philippines. Improved information leads new immigrants to acquire fewer new social...