There is a large literature on social interactions and still little is known about the economic mechanisms leading to the high level of clustering in behavior that is so commonly observed in the data. In this paper we present a model in which agents are allowed to interact according to three...

Aid programs in developing countries are likely to affect all households living in the treated areas, both eligible and non-eligible ones. Studies that focus on the treatment effect on the treated may fail to capture important spillover effects. We exploit the unique design of an aid program's...

The enlargement of the European Union has increased concerns about the role of generous welfare transfers in attracting migrants. This paper explores the issue of welfare migration across the 15 countries of the pre-enlargement Union and finds a significant but small effect of the generosity of...

"In this paper we investigate whether peers' behavior influences the choice of college major. Using a unique dataset of students at Bocconi University and exploiting the organization of teaching at this institution, we are able to identify the endogenous effect of peers on such decision through...