Beyond measuring average program impacts, it is important to understand how impacts vary. This paper gives a broad overview of the conceptual and statistical issues involved in using multisite randomized trials to learn about and from variation in program effects across individuals, across subgroups of individuals, and across program sites.
This paper explores the use of instrumental variables analysis with a multisite randomized trial to estimate the effect of a mediating variable on an outcome.
Despite the growing popularity of the use of regression discontinuity analysis, there is only a limited amount of accessible information to guide researchers in the implementation of this research design. This paper provides an overview of the approach and, in easy-to-understand language, offers best practices and general guidance for practitioners.
Using an alternative to classical statistics, this paper reanalyzes results from three published studies of interventions to increase employment and reduce welfare dependency. The analysis formally incorporates prior beliefs about the interventions, characterizing the results in terms of the distribution of possible effects, and generally confirms the earlier published findings.
No universal guideline exists for judging the practical importance of a standardized effect size, a measure of the magnitude of an intervention’s effects. This working paper argues that effect sizes should be interpreted using empirical benchmarks — and presents three types in the context of education research.