Identifying the precise effects of a policy is a complex and challenging task. This issue is particularly salient in an uncertain economic climate, where governments are under great pressure to promote programs that can recharge growth and reduce poverty. At the World Bank, our work is centered on aid effectiveness and how to improve the targeting and efficacy of programs that we support. As we are well aware, however, times of crisis as well as a multitude of other factors can inhibit a clear understanding of how interventions work—and how effective programs can be in the long run.
andbook on Impact Evaluation: Quantitative Methods and Practices makes a valuable contribution in this area by providing, for policy and research audiences, a comprehensive overview of steps in designing and evaluating programs amid uncertain and potentially confounding conditions. It draws from a rapidly expanding and broadbased literature on program evaluation—from monitoring and evaluation approaches
to experimental and nonexperimental econometric methods for designing and conducting impact evaluations.
Recent years have ushered in several benefits to policy makers in designing and evaluating programs, including improved data collection and better forums to share data and analysis across countries. Harnessing these benefits, however, depends on understanding local economic environments by using qualitative as well as quantitative approaches. Although this Handbook has a quantitative emphasis, several case studies are also presented of methods that use both approaches in designing and assessing programs.