When explaining the polarization of party systems, Satori’s (1976) typology represents one of the central concepts. Here the direction of party competition is affected by an occupied political centre and a bilateral opposition. The macro-level explanans and explanandum are based on the behavior of parties and voters. A party system will only polarize if the voting behavior and/or the party positions change. Thus, the following research question arises: Which influences on actors in party competition determine the correlation on the macro-level?
In the first step the link between coalition formation and the behavior of parties and voters is discussed. In the logic of Sartori the accountability of coalition parties, the cooperation of parties and the possible dissatisfaction of voters with the coalition are plausible factors. Secondly, these causal mechanisms are tested in an agent-based model. Lastly, the deduced hypotheses are tested in an empirical analysis.
