Explaining coalitions: A taxonomy of formal models of government formation and breakdown

Abstract

CCoalition theory is one of the fields that has extensively benefited from formal modelling in political science. Since the publication of William Riker’s (1962) seminal book, a variety of coalition models has been developed to explain government formation and breakdown. Nevertheless, despite the diversity of models, the literature seems to judge their predictability solely in terms of empirical tests, usually deriving hypotheses from their propositions and testing via statistics. In this work, I survey classical and more recent formal models in coalition theory, demonstrating how they serve different purposes. I build a taxonomy of models that acknowledges these purposes, and, more importantly, the roles they play in building explanations about coalitions. I identify three types of models: conceptual models, whose conceptual and theoretical value relies on the mathematical deductions entailed in the model; quasi-conceptual models, which formalise explanations of regularities in the real world; and extrapolative models, which allow for an empirical test of formal models via a variety of statistical methods. All of these types of models coexist, generating explanations and setting research agendas.