Poster #1 - Accounting for Student Attrition in Power Calculations: Benchmarks and Guidance

• In Event: 47.099 - MTCC Poster Session 11
  In Poster Session: 47.099-1 - Division D Section 2 Statistical Theory and Quantitative Methodologies

Abstract

The research methodology literature includes empirical benchmarks for effect sizes and intraclass correlations to help researchers conduct power analyses, but does not include similar benchmarks to account for attrition. To help fill this void, this paper describes how researchers can incorporate student attrition in power analyses and provides empirical benchmarks for the amount of attrition one might expect when conducting a school-based study that follows students over time. The paper incorporates parameters for student attrition in common minimum detectable effect size calculations, presents attrition benchmarks based on student mobility rates and a synthesis of published evaluation studies. The paper includes a demonstration of how researchers can use the attrition benchmarks to take student attrition into account in a power analysis.

Author

• Jordan Rickles, American Institutes for Research