Friendship Networks and Political Opinions

• 成果类型: Article
• 署名作者: Algan, Yann; Dalvit, Nicolo; Do, Quoc-Anh; Le Chapelain, Alexis; Zenou, Yves
• 署名单位: Hautes Etudes Commerciales (HEC) Paris; Centre for Economic Policy Research - UK; The World Bank; Monash University; Leibniz Association; Ifo Institut; University of Southampton
• 刊物名称: AMERICAN ECONOMIC REVIEW
• ISSN/ISSBN: 0002-8282; 1944-7981
• DOI: 10.1257/aer.20231344
• 发表日期: 2026-06
• 页码: 2202-2241
• 关键词: media; socialization; polarization; BEHAVIOR; IMPACT; memory; BIAS

摘要

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. (JEL C93, D72, Z13)