Determinants of Party Systems Size: Evidence from Europe and Latin America

Studies of party systems size have looked at institutional and sociological factors in their attempt to explain what determines the number of parties. Electoral rules and ethnic heterogeneity have been pointed out for years as the main factors affecting the number of parties that compete in elections. Furthermore, it has been shown that rules, beyond the district magnitude have a significant impact on, amongst others, new party entry. Rules however, differ substantially among countries and so does the existing party structure. Yet, we know very little about whether certain rules matter more in some societies than they do in others. Here, we study the extent to which party finance rules affect party system size and differentiate the effect between new and established democracies. We expect that in countries with more established democratic systems will be less vulnerable to the restrictive finance rules, than will new democracies, and that in addition to the effect of rules per se, there is also an effect related to the amount of change in the rules of the game. We test our expectations on data from Europe and Latin America.