matching

I’m often asked how the matching weights produced by MatchIt are computed. The weights are necessary for estimating the treatment effect in the matched sample; indeed, the weights determine the matched sample.

Genetic matching sounds cool and science-y, something we social scientists love because nobody thinks what we do is “real” science. And genetic matching is cool and science-y, but not because it has anything to do with genes or DNA.

Today I’m going to demonstrate performing a subgroup analysis after propensity score matching using R. Subgroup analysis, also known as moderation analysis or the analysis of effect modification, concerns the estimation of treatment effects within subgroups of a pre-treatment covariate.