More on Propensity Score Matching

Bill asked me to identify a few articles that employ propensity score matching. In the legal literature, I've seen few applications, and most of these have appeared in the work of Daniel Ho (Stanford Law School). Interested readers might want to consult two of his papers: one is a short comment on Richard Sanders' controversial affirmative-action study; the other is an article on Supreme Court decisionmaking in wartime (co-authored with Lee Epstein, Gary King, and Jeffrey Segal). The second paper is particularly valuable because it takes time to explain PSM to a legal audience.

Comments

[Jill Horwitz]

Here are two very useful citations for those who want to learn more about propensity scores:
Paul R. Rosenbaum & Donald B. Rubin, The Central Role of the Propensity Score in Observational Studies for Causal Effects, 70 Biometrika 41 (1983), Paul R. Rosenbaum & Donald B. Rubin, Reducing Bias in Observational Studies Using Subclassification on the Propensity Score, 79 Journal of the American Statistical Association 516 (1984).

I've used propensity scores as a sensitivity test (in published work and also in an article forthcoming in Yale J. Reg next month).

But like any method, it should only be used when there is good reason to think it will help explain data. In my case, I worried that my observations were correlated with a particular characteristic in such a way that controlling for that characteristic wouldn't be a sufficient.