手法を比較

	Government Formation Model	Coalition Formation Analysis
分野	Political Economy	Political Economy
系統	MCDM	MCDM
提唱年	1989	1962
提唱者	David Baron & John Ferejohn; David Austen-Smith & Jeffrey Banks	William Riker; Michael Laver & Norman Schofield
種類	Non-cooperative bargaining model of government formation	Formal theory of coalition selection
原典	Baron, D. P., & Ferejohn, J. A. (1989). Bargaining in Legislatures. American Political Science Review, 83(4), 1181-1206.	Riker, W. H. (1962). The Theory of Political Coalitions. Yale University Press. ISBN: 9780300001754
別名	Legislative Bargaining Model, Baron-Ferejohn Model, Formateur Model, Portfolio Allocation Model	Minimal Winning Coalition Theory, Riker Size Principle, Coalition Theory, Government Coalition Analysis
関連	4	4
概要	The government formation model is a non-cooperative bargaining theory explaining how a cabinet and the division of its portfolios emerge when no party holds a majority. In the canonical Baron-Ferejohn (1989) framework, a head of state or chance mechanism recognizes one party as formateur with a probability often proportional to its seat share; the formateur proposes a government and an allocation of the spoils of office, and the proposal takes effect only if a legislative majority accepts. Austen-Smith and Banks (1988) embed this in an electoral and coalition setting. The model's signature result is a proposer (formateur) advantage: the party that gets to propose secures a disproportionate share of portfolios.	Coalition formation analysis is the formal study of which subset of parties will combine to form a governing or decision-making coalition when no single party commands a majority. William Riker's 1962 The Theory of Political Coalitions supplied the foundational logic: under pure office-seeking, rational politicians form minimal winning coalitions and, by the size principle, the smallest winning coalition possible, so that the spoils of office are divided among as few partners as necessary. Michael Laver and Norman Schofield's 1990 Multiparty Government enriched this with policy-seeking motives, showing that coalitions also tend to be ideologically connected. The framework predicts coalition membership from seat shares and party positions.