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matheusfacure / python-causality-handbook

Causal Inference for the Brave and True. A light-hearted yet rigorous approach to learning about impact estimation and causality.
https://matheusfacure.github.io/python-causality-handbook/landing-page.html
MIT License
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Chapter 11: Possible typo in the description of IPTW #297

Closed loudly-soft closed 1 year ago

loudly-soft commented 1 year ago

Maybe I'm not reading this right. For the following sentence in Chapter 11:

This estimator is called the Inverse Probability of Treatment Weighting (IPTW), since it scales each unit by the probability of receiving some treatment other than the one it received.

I see in the formula that the treated is being scaled by 1/p(x) where p(x) is the probability of treated, while the untreated is being scaled by 1/(1-p(x)) where 1-p(x) is the probability of untreated.

Shouldn't the sentence read:

This estimator is called the Inverse Probability of Treatment Weighting (IPTW), since it scales each unit by the inverse probability of the treatment it received.