We provide the first empirical application of a new approach proposed by Lee (2007) to estimate peer effects in a linear-in-means model. This approach allows to control for group-level unobservables and to solve the reflection problem. We investigate peer effects in student achievement in...

I look at the equilibrium effects of homophily in network formation games having positive externalities. I show that very weak preferences for network effects (such as preference for being part of a clique) may result in very high levels of homophily at equilibrium. I present an empirical...

We propose a model of intergenerational transmission of education wherein children belong to either highly educated or low-educated families. Children choose the intensity of their social activities while parents decide how much educational effort to exert. Using data on adolescents in the...

We introduce uncertainty and risk aversion to the study of international environmental agreements. We consider a simple model with identical agents and linear payoffs. We show that a stable treaty with positive action always exists. While uncertainty lowers the actions of signatories, we find...

We study peer effects on the formation of beliefs regarding college participation. We present a structural model of learning in friendship networks. We show that the model is identified and we present a Bayesian estimation procedure. We estimate the model using data on teenagers’ beliefs...

Why are some cities specialised and others diversified? What are the advantages and disadvantages of urban specialisation and diversity? To what extent does the structure of cities, and the activities of firms and people in them, change over time? How does the sectoral composition of cities...