Heterogeneous peer effects in education

We investigate whether, how, and why individual education attainment depends on the educational attainment of schoolmates. Specifically, using longitudinal data on students and their friends in a nationally representative set of US schools, we consider the influence of different types of peers on educational outcomes. We find that there are strong and persistent peer effects in education, but peers tend to be influential in the long run only when their friendships last more than a year. This evidence is consistent with a network model in which convergence of preferences and the emergence of social norms among peers require long-term interactions.