Description:
This chapter discusses power and stability in politics and describes the applications of cooperative game theory to political science. The focus of the chapter is on the idea of power. The use of the Shapley and Banzhaf values for simple games to measure the power of political actors in voting situations, with a number of illustrative applications, is presented in the chapter. A voting situation can be modeled as a cooperative game in characteristic function form in which the value 1 is assigned to any coalition which can pass a bill and 0 to any coalition that cannot. The resulting game is known as a simple game. The coalitions that can pass bills are called winning coalitions, and the game is completely determined by its set of winning coalitions. If politics is the shaping of power, political actors might act to increase their power, and the rational choice assumption that they do so might have some explanatory efficacy in political dynamics. The chapter describes three possible situations of this type.