Bounding, an accessible method for estimating principal causal effects, examined and explained
Abstract
Estimating treatment effects for subgroups defined by post-treatment behavior (i.e., estimating causal effects in a principal stratification framework) can be technically challenging and heavily reliant on strong assumptions. We investigate an alternative path: using bounds to identify ranges of possible effects that are consistent with the data. This simple approach relies on fewer assumptions and yet can result in policy-relevant findings. As we show, covariates can be used to substantially tighten bounds in a straightforward manner. Via simulation, we demonstrate which types of covariates are maximally beneficial. We conclude with an analysis of a multi-site experimental study of Early College High Schools. When examining the program's impact on students completing the ninth grade "on-track" for college, we find little impact for ECHS students who would otherwise attend a high quality high school, but substantial effects for those who would not. This suggests potential benefit in expanding these programs in areas primarily served by lower quality schools.
Cite
@article{arxiv.1701.03139,
title = {Bounding, an accessible method for estimating principal causal effects, examined and explained},
author = {Luke Miratrix and Jane Furey and Avi Feller and Todd Grindal and Lindsay C. Page},
journal= {arXiv preprint arXiv:1701.03139},
year = {2017}
}