Re-evaluating the Theoretical Progress of Oversized Coalition Models from a Set Theoretical Perspective. An Analysis of Government Formation in Parliamentary Democracies

This article provides a set theoretical assessment of oversized coalition models. Coalition theory was established in the 1960s based on a minimalist approach and expects government formation by the smallest possible majority, the so-called ‘minimum winning coalition’. However, this approach neglects the question of why political parties sometimes seek to form oversized coalitions. A lot of studies from the 1970s onward attempted to give a systematic explanation of this puzzle that can be described as oversized coalition models. Although these models are confirmed by various statistical tests, there is no systematic evaluation through set theoretical methods, which can be understood as an alternative to correlation-based research strategies. Therefore, this article evaluates the models from a set theoretical perspective through Qualitative Comparative Analysis (QCA). Using the recently published powerful R package ‘QCA’, we finally capture both static (negated outcome) and dynamic characteristics (model development) of oversized coalition models.