Optimality of Matched-Pair Designs in Randomized Controlled Trials
Econometrics
2022-06-17 v1 Statistics Theory
Methodology
Statistics Theory
Abstract
In randomized controlled trials (RCTs), treatment is often assigned by stratified randomization. I show that among all stratified randomization schemes which treat all units with probability one half, a certain matched-pair design achieves the maximum statistical precision for estimating the average treatment effect (ATE). In an important special case, the optimal design pairs units according to the baseline outcome. In a simulation study based on datasets from 10 RCTs, this design lowers the standard error for the estimator of the ATE by 10% on average, and by up to 34%, relative to the original designs.
Cite
@article{arxiv.2206.07845,
title = {Optimality of Matched-Pair Designs in Randomized Controlled Trials},
author = {Yuehao Bai},
journal= {arXiv preprint arXiv:2206.07845},
year = {2022}
}