Voting Weights and Formateur Advantages in the Formation of Coalition Governments

Abstract

We examine the relationship between parliamentary seats and cabinet posts in European governments between 1946 and 2001. Our specification improves on past studies in two respects. First, it derives and uses the voting weights of the underlying coalition formation games. This reduces the measurement error introduced when seat shares are used to proxy for voting weights. Second, the statistical model allows us to nest the predictions of different formal theories of the distribution of posts. We find that for non-formateur parties in the government, there is a linear relationship between their share of the voting weight in parliament and their share of cabinet posts. Additionally, the formateur party receives a substantial bonus relative to its voting weight. The latter finding is more consistent with proposal-based bargaining models of coalition formation, and less so with demand-bargaining models.