Causal Inference, Instrumental Variables, Stats 361, Stanford, Data Science.
formula (9.6) without unconfoundedness is called IV Regression. Wager (2020) simply listed three conditions that Z_i has to meet as follows (the sentence after “;” is my own understanding): “Z_i must be exogenous”; in formula, ε_i ⊥⊥ Z_i (they are independent, no confounding factor between ε_i and