American Economic Review
ISSN 0002-8282 (Print) | ISSN 1944-7981 (Online)
Friendship Networks and Political Opinions
American Economic Review
(pp. 2202–41)
Abstract
We examine how social interactions and friendships shape students' political opinions in a natural experiment at Sciences Po, a leading French university specializing in social and political sciences. The quasi-random assignment of students into short-term integration groups before their academic curriculum reduces political opinion gaps and fosters friendship formation. Using same-group membership as an instrumental variable for friendship, we find that friendship reduces opinion differences by 44 percent of the mean opinion gap. Our evidence supports a homophily-enforced mechanism: Friendships form among initially politically similar students, leading them to join political associations together, reinforcing their similarity.Citation
Algan, Yann, Nicolò Dalvit, Quoc-Anh Do, Alexis Le Chapelain, and Yves Zenou. 2026. "Friendship Networks and Political Opinions." American Economic Review 116 (6): 2202–41. DOI: 10.1257/aer.20231344Additional Materials
JEL Classification
- C93 Field Experiments
- D72 Political Processes: Rent-seeking, Lobbying, Elections, Legislatures, and Voting Behavior
- Z13 Economic Sociology; Economic Anthropology; Language; Social and Economic Stratification