Research Details

Abstract

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 curriculum, and use the pairwise indicator of same-group membership as instrumental variable for friendship. After six months, friendship causes a reduction of differences in opinions by one third of the standard deviation of opinion gap. The evidence is consistent with a homophily-enforced mechanism, by which friendship causes initially politically-similar students to join political associations together, which reinforces their political similarity, without exercising an effect on initially politically-dissimilar pairs. Friendship affects opinion gaps by reducing divergence, therefore polarization and extremism, without forcing individuals' views to converge. Network characteristics also matter to the friendship effect.

Type

Working Paper

Author(s)

Yann Algan, Nicolò Dalvit, Quoc-Anh Do, Yves Zenoou

Date Published

2020

Citations

Algan, Yann, Nicolò Dalvit, Quoc-Anh Do, and Yves Zenoou. 2020. Friendship Networks and Political Opinions: A Natural Experiment among Future French Politicians.