Randomized experiments involving education interventions are typically implemented as cluster randomized trials, with schools serving as clusters. To design such a study, it is critical to understand the degree to which learning outcomes vary between versus within clusters (schools), specifically the intraclass correlation coefficient. It is also…

Educational stakeholders are keen to know the magnitude and importance of different interventions. However, the way evidence is communicated to support understanding of the effectiveness of an intervention is controversial. Typically studies in education have used the standardised mean difference as a measure of the impact of interventions. This…

Accelerated Reader™ is a computerized supplementary reading program that provides guided reading instruction to students in grades K-12. It aims to improve students' reading skills through reading practice and by providing frequent feedback on students' progress to teachers. The Accelerated Reader™ program requires students to select and read a…