The political foundations of party organizational variance

The aim of this contribution is twofold: first, to verify empirically how and to what extent party organizations vary within countries, in time; second, to enhance the role of political factors in explaining organizational variance. While mainstream literature has generally overestimated cross-national party convergence, a renewed interest in the study of variance has recently gained ground. We thus focus on seven European countries, from 1990 to 2010, by combining party organizational data from the Party Organization Data Handbook and the Political Party Database Project, with domestic cultural, socioeconomic, technological data from the European Values Survey and the World Bank, as well as supranational economic data provided by the OECD. We are interested in verifying how much of the variance in party organizations can be explained by resorting to the parameters of the party systems vis-à-vis domestic and supranational extra-political factors. Our results show that the explanatory power of party systems’ parameters is stronger than the predictive ability of contextual variables.