More Political Power

Abstract

We continue our study of political power in this chapter, beginning in Sections 9.2 and 9.3 with two more quantitative measures of power. Both of these power indices were introduced in the late 1970s, the first appearing in Johnston (1978) and the second in Deegan-Packel (1978). These indices are similar in some ways to the Shapley-Shubik and Banzhaf indices introduced in Chapter 4, but they also differ in some important respects from these earlier ones as well as from each other. In Section 9.4 we build on work of Brams, Affuso, and Kilgour (1989) in applying all four of these different indices to measure the power of the president in the context of the United States federal system. It turns out, for example, that according to the Deegan-Packel index, the president has less than 1 percent of the power. The Johnston index, however, suggests that the president has 77 percent of the power.