Multiple choice: Policy substitution and complementarity with heterogeneity

Despite significant attention to the determinants of policy choices, the heterogeneity of the policymakers and the relations among policies have received scant attention. Bringing these two underdeveloped areas of scholarship together, this dissertation weaves together four essays modeling foreign policy choice in the presence of multiple related instruments with heterogeneous agents, examining choice under constraints implied by theories from international macroeconomics, international relations, and partisan political economy.; The first essay develops and tests a choice-theoretic Mundell-Fleming model. I derive the expectation that the relationship among capital controls and the exchange rate regime should differ on the basis of government partisanship. Quantitative evidence reveals that governments representing the political Left are more likely to implement controls on international capital and fix the exchange rate, while other governments prefer open capital markets or more flexible exchange rates.; Turning to a global sample, a multinomial Markov model demonstrates strong influences of domestic politics on de facto exchange rate regimes. Democratic governments are significantly more likely to avoid fixed de facto exchange rate regimes; Left governments are more likely to seek fixed exchange rates because of inherent credibility problems that arise from the preferences of Left governments.; In a reevaluation of studies relating political instability and exchange rate regime choice, I demonstrate that political instability is related to exchange rate regime choice, but this relationship critically depends on political institutions. Democracies facing political instability seek intermediate, and manipulable, exchange rate policies while nondemocracies respond to instability with an increasing likelihood of polar exchange rate regimes.; I conclude by presenting Monte Carlo evidence of the efficacy of simultaneous pro-bit models for studying policy substitution. Applying these models, I show that Democratic presidents complement economic sanctions with military force while Republican presidents substitute among sanctions and force, but employ a coercive tool with considerably greater frequency.; These essays showcase the importance of models for multiple interrelated policies and the importance of characteristics of the decision maker for understanding choice in international politics. I provide novel theoretical and empirical insights into the determinants and interrelations among important choices facing policy makers in the international arena.