Question on page /22-Debiased-Orthogonal-Machine-Learning.html

[teemingyi]

Hi, just wanted to ask a question on the section CATE Estimation with Double-ML.

For the final CATE model, I noticed that the formula did not include a term for the covariates Xi.

I was wondering if it is necessary to include the covariates in the CATE model. By the codes, I think they are already included by default.

I am comparing this formula with the one used in chapter 18, under the section Predicting Elasticity.