The Polarity Problem: Analyzing the Effect of Party Systems on Affective Polarization Schmidt, Cassandra Affective PolarizationTwo-Party SystemPolarizationParty SystemUnited StatesLeader Affective PolarizationParty Affective PolarizationPartisanPolitical ScienceB AAffective polarization, or the phenomenon that captures individuals’ negative feelings towards members of the out-group and positive feelings towards in-group members, has become a staple in modern day politics. It is apparent in everything from media presentations to household conversations. Despite its prevalence in society, research into how it develops and grows is relatively new. This thesis explores the role that the number of parties in a system plays on the amount of affective polarization in a country. Using multiple regressions tests run on data gathered by the Comparative Study of Electoral Systems, I discover that affective polarization rates are higher among partisan voters in countries with fewer parties. Additionally, I discovered that populations tend to deem parties more polarizing than the leaders themselves. These discoveries indicate that the number of parties in a system do affect the overall rates of affective polarization in countries and should be considered a part of its cause and the rapid rate at which it increases in some countries. Joseph Wright, Thesis SupervisorSona N. Golder, Thesis Honors Advisoropen_access2025-03-31T23:50:07Zhttps://honors.libraries.psu.edu/catalog/9689cas7536