The short-term and long-term effects of institutional reforms on party system nationalization

The impact of institutions on party system nationalization has traditionally been examined in a cross-national fashion. However, while in some cases institutional reforms may be expected to immediately affect party nationalization, in others, changes might take place over subsequent elections. In this paper, we argue that reforms affecting mainly elite coordination-such as decentralization-will take a longer time to have an impact on party system nationalization than reforms related to the mechanical effects of electoral laws, i.e. changes in the electoral system. In order to test this argument, we use error-correction models to test the impact of electoral reforms on party system nationalization in democratic elections held in 22 Western and Eastern European countries from 1945 to 2012. In accordance with our arguments, we show that both decentralization and the number of districts elected in the legislative power will have an impact on party system nationalization, but that the impact of the latter will manifest itself earlier