Dynamic ideal point estimation for the European Parliament, 1980–2009

The European Parliament is one of most prominent substantive applications of NOMINATE to the study of roll call voting outside the U.S., yielding tremendous insights into the voting patterns of the world’s most important transnational parliament. However, this body of research cannot facilitate comparisons of ideological shifts over time, because it exclusively employs scaling models that are static. In this paper, I produce dynamic ideal point estimates for the first six European Parliaments from 1980 to 2009 that can be compared over time. These estimates show a significant amount of ideological shifting for some Members of the European Parliament. I explain the measurement strategy, and compare cross-sectional estimates to existing measures as a validity check. I also offer three applications highlighting the types projects that scholars of the European Parliament might wish to use these dynamic measures to study further.