Why do states choose multilateralism? We develop an argument focused on the burden-sharing versus control dilemma of principal-agent (PA) models. We also present two alternative theoretical frames that could explain this choice: a normative logic of appropriateness and hegemonic self binding. We examine the political bases of support for sending foreign aid through multilateral versus bilateral channels. First, we clarify the concept of multilateralism. We show that the choices for internationalism and multilateralism are distinct. Second, we develop hypotheses from each of the three theories and examine how public opinion data allow us to shed light on these different theories about multilateralism. Finally, we provide evidence about the correlates of public support for multilateral engagement. We isolate how two competing rationales—burden sharing and control—dictate some of the politics around the choice between multilateral versus bilateral aid channels. The data support our claim that a principal-agent model can help us to understand the choice for multilateralism.

Why have developing countries increasingly opened their economies to trade? Research about trade policy in developed countries has focused on a bottom up process by identifying the economic preferences of domestic groups. We know less about preferences in developing countries. To explore this, we focus on the micro level and explore one country’s decision making in a systematic fashion, rather than using a cross-national analysis. We analyze how economic and political variables influenced Costa Rican voters in a referendum on CAFTA, an international trade agreement. We find surprisingly little support for Stolper-Samuelson models of economic preferences and instead find more support for skill-biased trade theories. Furthermore, we isolate the effects of political parties on the referendum vote; we document how at least one party influenced voters and this made the difference for CAFTA passage. Politics, in the form of parties using their organizational strength to cue and frame messages for voters, influenced an important trade policy decision. Theories about trade policy in developing countries need to take into account the impact of top-down political factors such as parties and message framing.

Experimentation is a powerful methodology that enables scientists to empirically establish causal claims. However, one important criticism is that experiments merely provide a black-box view of causality and fail to identify causal mechanisms. Critics argue that although experiments can identify average causal effects, they cannot explain how such effects come about. If true, this represents a serious limitation of experimentation, especially for social and medical science research whose primary goal is to identify causal mechanisms. In this paper, we consider several different experimental designs and compare their identification power. Some of these designs require the direct manipulation of mechanisms, while others can be used even when only imperfect manipulation is possible. We use recent social science experiments to illustrate the key ideas that underlie each design.