We study how friendship shapes students' political opinions in a natural experiment. We use the indicator whether two students were exogenously assigned to a short-term \integration group", unrelated to scholar activities and dissolved before the school year, as instrumental variable for their...

We study how social interaction and friendship shape students' political opinions in a natural experiment at Sciences Po, the cradle of top French politicians. We exploit arbitrary assignments of students into short-term integration groups before their scholar cursus, and use the pairwise...

This paper uses the unique social structure of Arab communities to examine the effect of social identity on voter turnout. We first show that voters are more likely to vote for a candidate who shares their social group (signified by last name) as compared to other candidates. Using last name as...

We consider the spread of a harmful state through a population divided into two groups. Interaction patterns capture the full spectrum of assortativity possibilities. We show that a central planner who aims for eradication optimally either divides equally the resources across groups, or...