The politics of coalition formation and survival in multi-party presidential democracies - The case of Uruguay, 1989-1999

The study of coalition formation has primarily focused on the analysis of parliamentary regimes. This article examines the dynamics of coalition formation and breakdown under presidential regimes using evidence from Uruguay (1989-99). Using logistic regression I show that while coalitions are more likely to form immediately after a presidential election, the probability of a political group remaining in an executive coalition decreases as the presidential term elapses. As a result, cycles of cooperation and stalemate among political actors are likely to occur. I also conclude that not only the prospects for political cooperation but also the likelihood of a given fraction leaving a governing coalition are explained by the following variables: ideological affinity between the president's fraction and another political group; presidential approval ratings; affiliation of a fraction with the president's party; proximity of the coming election; and the fairness of the coalition agreement.