Coalition governments in a model of parliamentary democracy

We analyse a model of coalition government in a parliamentary democracy where parties care both for ideology and perks from office, and examine how the magnitude of this tradeoff affects the nature of coalitions that form. It is shown that equilibrium coalitions can be minimal winning, minority or surplus and they may be ideologically disconnected. The types of coalitions that emerge depend upon the relative importance of rents from office and the distribution of party ideologies. Further, there is a non-monotonic relationship between ideological connectedness of coalitions and rents from office.