Optimal Design of Experimental Studies Investigating Moderation and Main Effects

• Sponsor
  Spencer Foundation Research Grant-Large
  $362,220

• Principal investigator
  Zuchao William Shen
  Assistant professor, Department of Educational Psychology
  

• Co-principal investigator
  Ben Kelcey
  Professor of quantitative research methodology, University of Cincinnati
  

• Active since
  August 2023

Abstract

Experimental studies investigating moderation and main effects provide the source material for improving the quality of and equity in education by delineating the impact of an intervention, and the contexts, conditions, and sub-populations for which it is most effective. Despite sustained interest in experimental studies, the literature has not developed accessible optimal sampling strategies to help plan powerful and efficient designs to detect these effects.

This project aims to develop a flexible optimal design framework so that we can design well-powered studies with minimal financial resources.

Specifically, this project will:

• Incorporate flexible costs structures of sampling
• Cover single-level experiments, two-, and three-level cluster-randomized trials, and multisite-randomized trials with continuous and binary moderators at different levels
• Identify samples that are jointly optimal for main and moderation effects
• Investigate the robustness of the proposed framework against the misspecification of design parameters
• Implement the methods in the R package odr and a shiny app

Preliminary results show that the proposed framework can identify much more efficient or powerful designs when contrasted with conventional design frameworks. This project has the potential for broad impacts because it facilitates a fundamental shift in the principles and strategies of study design.