An Introduction to Alternative Methods in Program Impact Evaluation

This paper presents an overview of several widely-used methods in program impact evaluation. In addition to a randomization-based method, these methods are categorized into: (i) methods assuming “selection on observable” and (ii) methods assuming “selection on unobservable”. The paper discusses each method under identification assumptions and estimation strategy. Identification assumptions are presented in a unified framework of counterfactual and two equation model. Finally, the paper uses simulated data to illustrate how these methods work under different identification assumptions.