Assessing the Impact of Age, Cohort and Period Effects on Partisanship and Support for Mainstream Parties: Evidence from Southern Europe

The article examines the link between time effects and dealignment in Southern European countries, which allows us to assess the relative importance of short- and long-term factors on the political instability of the region during the Eurocrisis. First, we analyse life cycle, cohort and period effects on partisan identities across countries. Second, we investigate to what extent time-related factors have been responsible for the erosion of the vote in mainstream parties, especially during the crisis period, thus isolating the impact of time on general patterns of party system change. Our results show that electoral and partisan dealignment is fostered in particular by period effects, whereas age and cohort differences play a more limited role. In addition, there are also important differences across countries in terms of both evolution and intensity of time effects.