COBRA: Contextual Bandit Algorithm for Ensuring Truthful Strategic Agents
Abstract
This paper considers a contextual bandit problem involving multiple agents, where a learner sequentially observes the contexts and the agent's reported arms, and then selects the arm that maximizes the system's overall reward. Existing work in contextual bandits assumes that agents truthfully report their arms, which is unrealistic in many real-life applications. For instance, consider an online platform with multiple sellers; some sellers may misrepresent product quality to gain an advantage, such as having the platform preferentially recommend their products to online users. To address this challenge, we propose an algorithm, COBRA, for contextual bandit problems involving strategic agents that disincentivize their strategic behavior without using any monetary incentives, while having incentive compatibility and a sub-linear regret guarantee. Our experimental results also validate the different performance aspects of our proposed algorithm.
Cite
@article{arxiv.2505.23720,
title = {COBRA: Contextual Bandit Algorithm for Ensuring Truthful Strategic Agents},
author = {Arun Verma and Indrajit Saha and Makoto Yokoo and Bryan Kian Hsiang Low},
journal= {arXiv preprint arXiv:2505.23720},
year = {2025}
}
Comments
This paper proposes a contextual bandit algorithm that prevents strategic agents from misreporting while having approximate incentive compatibility and a sub-linear regret guarantee