With this assumption in hand, then the causal effects of T , E Var Y (T ) C, {Y (t)} t∈T , matches I(L) as described in equation (1) (Imbens and Rubin, 2015).
given the same assumptions often made in observational studies, the informativeness coefficient of the full, uncompressed text in fact corresponds to the amount of variation in Y due to the causal effects of T .