We study the effects of informal social interactions on academic achievement and behaviour using idiosyncratic variation in peer groups stemming from changes in bus routes across elementary, middle, and high school. Our results suggest that student interactions outside the classroom—especially...

Inequality of opportunity, particularly when overlaid with racial, ethnic, or cultural differences, increases the social distance between individuals, which is widely believed to limit the scope of cooperation. A central question, then, is how to bridge such divides. We study the effects of a...

Observability has been demonstrated to influence the adoption of pro-social behavior in a variety of contexts. This study implements a field experiment to examine the influence of observability in the context of a novel pro-social behavior: peer-to-peer solar. Peer-to-peer solar offers an...

We merge experimental data on competitiveness of a large sample of students with their complete educational history for up to ten years after the initial assessment. Exploiting quasi-random class assignments, we find that having competitive peers as classmates makes students choose and secure...

Democratic societies are challenged by various violent and organized groups, be they terrorists, gangs or organized hooligans. In exchange for offering an identity, leaders in such groups typically require members to be violent. We introduce a simple model to capture these stylized facts, and...

For a country fractionalized in competing factions, each owning part of the stock of natural exhaustible resources, or with insecure property rights, we analyze how resources are transformed into productive capital to sustain consumption. We allow property rights to improve as the country...

The present paper analyzes situations in which groups compete for rents. A major result in the literature has been that there are both cases where larger groups have advantages and cases where they have disadvantages. The paper provides two intuitive criteria which for groups with homogenous...