방법 비교

	Government Formation Model	Voting Power Index Analysis
분야	Political Economy	Political Science
계열	MCDM	MCDM
기원 연도	1989	1954
창시자	David Baron & John Ferejohn; David Austen-Smith & Jeffrey Banks	Lloyd Shapley & Martin Shubik; John F. Banzhaf III
유형	Non-cooperative bargaining model of government formation	Cooperative game-theoretic measure of a priori voting power
원전	Baron, D. P., & Ferejohn, J. A. (1989). Bargaining in Legislatures. American Political Science Review, 83(4), 1181-1206.	Shapley, L. S., & Shubik, M. (1954). A Method for Evaluating the Distribution of Power in a Committee System. American Political Science Review, 48(3), 787-792.
별칭	Legislative Bargaining Model, Baron-Ferejohn Model, Formateur Model, Portfolio Allocation Model	Voting Power Index, Shapley-Shubik Index, Banzhaf Power Index, A Priori Voting Power Analysis
관련	4	4
요약	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.	Voting power index analysis measures the a priori capacity of each member of a weighted voting body to influence collective decisions, defined as the probability that the member is pivotal — that their vote turns a losing coalition into a winning one. The two canonical indices are the Shapley-Shubik index, introduced by Lloyd Shapley and Martin Shubik in 1954 as a specialization of the Shapley value to simple voting games, and the Banzhaf index, formalized by John Banzhaf in 1965. Both reveal that a player's share of power generally differs sharply from its share of votes.