This paper endeavors to augment the robustness of offline reinforcement learning (RL) in scenarios laden with heavy-tailed rewards, a prevalent circumstance in real-world applications. We propose two algorithmic frameworks, ROAM and ROOM, for robust off-policy evaluation (OPE) and offline policy optimization (OPO), respectively. Central to our frameworks is the strategic incorporation of the median-of-means method with offline RL, enabling straightforward uncertainty estimation for the value function estimator. This not only adheres to the principle of pessimism in OPO but also adeptly manages heavy-tailed rewards. Theoretical results and extensive experiments demonstrate that our two frameworks outperform existing methods on the logged dataset exhibits heavy-tailed reward distributions.

这篇论文旨在增强离线强化学习在实际应用场景中具有重尾奖励的鲁棒性。我们提出了两个算法框架ROAM和ROOM，分别用于鲁棒的离线策略评估和离线策略优化。这些框架的核心是将均值中位数方法与离线强化学习相结合，从而能够直接估计值函数估计器的不确定性。理论结果和广泛的实验证明，我们的两个框架在具有重尾奖励分布的日志数据集上优于现有方法。

使用重尾分布奖励的鲁棒离线策略评估和优化