”Data Challenges in Empirical Political Research: Experiments, Legislative Data, and Comparative Surveys” by Marta Gallina (Catholic University of Lille) and Stefano Camatarri (Catholic University of Louvain) , July 9 at 13:10-

リール・カトリック大学のMarta Gallina准教授とルーヴァン・カトリック大学のStefano Camatarri博士をお迎えし、ワークショップを開催します。
どなたでもご参加いただけます。事前登録は不要です。ぜひご参加下さい。
We are very pleased to host Associate Professor Marta Gallina (Catholic University of Lille) and Dr. Stefano Camatarri (Catholic University of Louvain) for a special talk. Pre-registration is not required. We look forward to your participation. 

日時：2026年7月9日（木）13:10 pm – 14:50 pm 

Date and Time: Thursday, July 9, 2026, 13:10 pm – 14:50 pm

場所：3号館1106
Venue： Room 1106, Building 3, Waseda Campus, Waseda University

言語 Language：英語English

タイトル Title： Reducing Affective Polarization through Diversity Exposure: Evidence from a VAA Field Experiment in Japan

Collaborators: 
Airo Hino (Waseda University), Marta Gallina (Catholic University of Lille), Stefano Camatarri (Catholic University of Louvain), Robert Andrew Fahey (Waseda University), Uwe Serdült (Ritsumeikan University and University of Zurich) 

要旨Abstract：
This paper investigates whether Voting Advice Applications (VAAs), by exposing voters to a diverse set of politically relevant alternatives, can reduce affective polarization. While VAAs are primarily designed to inform electoral choices and increase political knowledge, we argue that their personalized presentation of ideologically diverse parties may also mitigate negative attitudes toward political outgroups. Drawing on a randomized field experiment conducted in 2024 in Japan, a context characterized by a long-term reign of a governing party and a dominant-party system, we find that exposure to a VAA significantly reduces affective polarization. Notably, the effect is strongest among voters who typically rely on valence-based evaluations rather than issue-based reasoning, i.e. supporters of the dominant Liberal Democratic Party (LDP). These findings suggest that VAAs, beyond their intended informational and educational functions, can serve as effective tools for mitigating partisan hostility by broadening voters’ perceived political choice set. However, the effect appears to be short-lived, fading after the election period.

共催：
早稲田大学高等研究所
Waseda Institute for Advanced Study (WIAS)
現代政治経済研究所　世論・メディアデータ研究部会
Public Opinion and Media Data Research Group, WINPEC, Waseda University

Contact： 日野愛郎（早稲田大学） Airo Hino (Waseda University)  [email protected]