Authors: Nohlen
Summary: In about 1300 words the entry contrasts narrow political understandings of the term with more general social conceptions, discusses factors influencing the form political party- coalitions take, and reflects on the foundational studies in game-theory and their critics. The entry cites several definitions that understand the term as a general social phenomenon and contrasts those with conceptions that focus on the political arena. The word coalition is commonly used to describe any group of people that comes together for a certain end. More narrow conceptions focus on the process of party-coalition building. For the latter, four influential determinants of the form coalitions take and the process of coalition-building are identified. The structure of the political system (parliamentary vs. presidential), the electoral system (majority vs. representational), the structure of the party system (two-party vs. multi-party), and the societal cleavages and conflict potential are identified as factors on which a theory of political coalition-building could rest. But so far no general theory has been developed. Game theorists have studied the problem of how and why coalitions are formed since the 1960s and 1970s, and understand coalition building as a common form of social organization in and outside of the domestic and international political realm. Efforts have focused to simulate coalition games in order to determine the variables influential on actors coalition decisions. But as the entry clarifies, so far primarily normative theories have been developed, that tell actors what they should do. Game theory has been rather unsuccessful in specifying the coalitional behavior of actors in reality. Critics have, therefore, pointed out that game theoretic approaches to understand coalition building processes underestimate the importance of factors such as ideology and identity on the one hand, and institutional structure on the other.