  The best empirical research in political science clearly defines substantive
parameters of interest, presents a set of assumptions that guarantee its
identification, and uses an appropriate estimator. We argue for the importance
of explicitly integrating rigorous theory into this process and focus on the
advantages of doing so. By integrating theoretical structure into one's
empirical strategy, researchers can quantify the effects of competing
mechanisms, consider the ex-ante effects of new policies, extrapolate findings
to new environments, estimate model-specific theoretical parameters, evaluate
the fit of a theoretical model, and test competing models that aim to explain
the same phenomena. As a guide to such a methodology, we provide an overview of
structural estimation, including formal definitions, implementation
suggestions, examples, and comparisons to other methods.
