Disclaimer. Don't rely on these old notes in lieu of reading the literature, but they can jog your memory. As a grad student long ago, my peers and I collaborated to write and exchange summaries of political science research. I posted them to a wiki-style website. "Wikisum" is now dead but archived here. I cannot vouch for these notes' accuracy, nor can I even say who wrote them. If you have more recent summaries to add to this collection, send them my way I guess. Sorry for the ads; they cover the costs of keeping this online.
Laver and Shepsle. 1990. Coalitions and Cabinet Government. American Political Science Review 84 (Sept): 873-890.
Unlike passing a bill or "dividing a dollar," forming a coalition is not the end of politics, but the beginning. Thus, the last three decades' models about coalition-forming that are based on theories of voting in legislatures have missed the boat. When forming a coalition, "rational actors must entertain expectations of subsequent government behavior." This article presents "a model of rational expectations with an emphasis on the credibility of the policy promises of prospective government partners as determined by the allocation of portfolios in the new government. Portfolio allocation becomes the mechanism by which prospective coalitions make credible promises and so inform the expectations of rational agents in the coalition formation process." In other words, legislators decide whether to support a proposed coalition based on which parties control which portfolios, not based on the coalition's policy promises. The coalition cannot make credible policy promises unless they assign portfolios to parties with reputations consistent with these promises.
This is similar to Shepsle and Weingast's arguments in the 1980s about committee logrolls in the US House.
Research by the same authors
Research on similar subjects