ABSTRACT
This chapter addresses the key issues and conceptual frameworks involved in trying to evaluate the actual impact of public policy. Impact analysis is actually one part of a much broader field of policy studies called program evaluation. Like policy analysis, impact analysis has struggled with the question of how to go about answering the questions that define it as a field of study. Impact analysis is squarely in the rationalist tradition, and the same post-positivist criticisms that are launched against policy analysis are also made against impact analysis. Impact analysis is subject to a broad set of objections from post-positivist critics. These criticisms have some merit. An impact analysis is wholly dependent on generating a valid estimate of the counterfactual, and this is possible only if the correct activity and outcome of interest have been identified and accurately measured, the causal link connecting them is accurately understood, and these elements are brought together in a robust and well-thought-out research design.
