Heckman, James J.; Ichimura, Hidehiko; Smith, Jeffrey A.; … - 2021
This paper develops and applies semiparametric econometric methods to estimate the form of selection bias that arises … econometric selection model which represents the bias solely as a function of the probability of participation; and (c) the method … of difference-in-differences. Using data from an experiment on a prototypical social program combined with unusually rich …