Causality, Causal Inference, Backdoor, Frontdoor, Instrumental Variable.
estimated if we measure any of these three sets: {X, Y, BD}, {X, Y, IV}, or {X, Y, FD} Suppose that X is a binary variable indicating the effect of exercising at least weekly (x = 1 if exercising; x = 0 otherwise) and Y is life expectancy measured on a continuous scale. The effect of X on Y is