Estimating local average treatment effects in aggregate data

摘要

In some contexts, the effect of a treatment can be estimated with easily accessible aggregate rather than individual data, using difference-in-difference estimation. However, under imperfect assignment within groups, this produces intent-to-treat estimates, which may not be the treatment effect of interest. This article provides a method for estimating local average treatment effects using aggregate data. I also suggest a data source that allows the method to be applied when treatment rates are not recorded.