Work

Robust Sequential Experimental Design for A/B Testing

Year: 2026

Type: article

Abstract: Experimental design has emerged as a powerful approach for improving the sample efficiency of A/B testing, yet existing designs rely critically on correctly specified models. We study robust sequential experimental design under model misspecification and develop a unified framework that covers both contextual bandit and dynamic settings. Theoretically, we prove that our design bounds the worst-case mean squared error of the estimated treatment effect. Empirically, we demonstrate the effectiveness of the proposed approach using synthetic and real-world datasets from a leading technology company.

Source: London School of Economics and Political Science Theses Online (London School of Economics and Political Science)

DOI: 10.48550/arxiv.2605.12899