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.
Publications
Empirical Guidance for Studies That Randomize Schools to Measure the Impacts of Educational Interventions
This paper examines how controlling statistically for baseline covariates (especially pretests) improves the precision of studies that randomize schools to measure the impacts of educational interventions on student achievement.
New Directions in Evaluations of American Welfare-to-Work and Employment Initiatives
Methodological Lessons from an Evaluation of Accelerated Schools
The Effects of Program Management and Services, Economic Environment, and Client Characteristics