Research design and estimator choices in the analysis of interstate dyads: When decisions matter

Researchers face three basic questions when testing theoretically driven hypotheses. First is research design: for example, what population should be analyzed, what sample should be drawn from that population, and what cases should be excluded from the sample? What statistical estimator should one use? What set of control variables should one employ? Results drawn from several permutations of the Correlates of War Militarized Interstate Dispute data set are compared using three statistical models. For some theories and variables (international institutionalism - intergovernmental organization and alliance membership; realism - balance of power; expected utility theory - international interaction game equilibria), research design and estimator choices substantially influence the findings. For others (trade and democratic peace theory), the relationship between the dependent and independent variables is relatively impervious to research design and estimator choices.