The Owen and Shapley spatial power indices: A comparison and a generalization.

Spatial games take into account the position of any voter in the space. In this class of games, two main indices of political power were defined. The first by Owen (1971) and the second, by Shapley (1977), later on extended in a two-dimensional space by Owen and Shapley (1989). We propose a generalization of Owen index. We show that the method proposed by this later in which players ordering is based on the distance between bliss and political issues points, yields the Shapley index if issues can be any point in the space.