Coalition Formation Theories Revisited: An Empirical Investigation of Aumann's Hypothesis.

In one of the earliest attempts to examine the effect of a priori voting power on actual political phenomena, Riker (1959) looked at changes in party affiliation in the French National Assembly in 1953-54, and used these data to test the hypothesis that deputies who switched parties were seeking thereby to increase their a priori voting power. His findings were negative, or at best inconclusive. [ABSTRACT FROM AUTHOR]