Measuring Political Polarization in Comparative Perspective

Abstract

I show that the available measures of polarization proposed in the economics and political science literatures present shortcomings when applied to the measurement of party system polarization, and I introduce a new measure of ideological polarization that displays desirable properties in line with the political science concept. The measure is applied to data from voters surveys, expert party placements, and manifesto data. I then present an application, detecting systematic patterns in the relationship between electoral rules, income distribution, and party system polarization.