I am familiar with Inverse Propensity Weighting (IPW) for the estimation of causal effects, and recently, I came across the 2016 paper by Chernozhukov et al. on Double/Debiased Machine Learning. From what I can see, both DML and IPW make similar assumptions over the causal structural equations: is there any reason why I would choose one approach over the other when estimating the ATE or CATE?
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3$\begingroup$ Mostly a rule of cool situation. (Someone will make the case about non-linearities too. Maybe we get a mention of Causal Forests and a historical reference to doubly robust methods.) (+1 cause I am curious for any other half-reasonable points - oh and welcome to CV.SE) $\endgroup$– usεr11852Mar 24, 2022 at 1:40
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1$\begingroup$ Check out this related question. In short: DML uses a doubly-robust estimator; IPW is singly robust except for a few specific methods. The causal identification assumptions are the same; they differ in their ability to remove confounding by the observed variables. $\endgroup$– NoahMar 24, 2022 at 3:58
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1$\begingroup$ Look up AIPW vs IPW. Double ML for the ATE is pretty much just the decades-old AIPW estimator combined with cross-fitting of nuisance estimators (which goes back decades as well). This writeup looks good: scholar.harvard.edu/files/aglynn/files/AIPW.pdf $\endgroup$– LarsApr 15, 2022 at 2:47