Journal Article

Powerful and Robust Test Statistic for Randomization Inference in Group‐Randomized Trials with Matched Pairs of Groups

Traskin, Mikhail, Small, Dylan S., Zhang, Kai

2012

Overview

For group‐randomized trials, randomization inference based on rank statistics provides robust, exact inference against nonnormal distributions. However, in a matched‐pair design, the currently available rank‐based statistics lose significant power compared to normal linear mixed model (LMM) test statistics when the LMM is true. In this article, we investigate and develop an optimal test statistic over all statistics in the form of the weighted sum of signed Mann‐Whitney‐Wilcoxon statistics under certain assumptions. This test is almost as powerful as the LMM even when the LMM is true, but it is much more powerful for heavy tailed distributions. A simulation study is conducted to examine the power.

• Publisher: Blackwell Publishing Inc,Wiley-Blackwell,Blackwell Publishing Ltd
• Subject: BIOMETRIC METHODOLOGY / Biometrics / biometry / Case-Control Studies / Causal effect / Control units / Correlations / Data Interpretation, Statistical / Depressive disorders / Experimentation / Generalized linear models / Group-randomized trials / Inference / Probabilities / Probability distribution / Random Allocation / Random variables / Randomization inference / Randomized Controlled Trials as Topic - methods / Randomized Controlled Trials as Topic - statistics & numerical data / Rank-based statistics / Robustness / statistical models / Statistical variance / Statistics / Statistics, Nonparametric