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20222025
most citedDoubly Robust Distributionally Robust Off-Policy Evaluation and Learning

2 citations · 8 across the 12 of their papers we have counts for

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Showing 2024Show all

5 papers · 1 filter

stat.ML2024★ 1 cited

The Central Role of the Loss Function in Reinforcement Learning

Kaiwen Wang, Nathan Kallus, Wen Sun

This paper illustrates the central role of loss functions in data-driven decision making, providing a comprehensive survey on their influence in cost-sensitive classification (CSC)…

cs.AI2024

Efficient and Sharp Off-Policy Evaluation in Robust Markov Decision Processes

Andrew Bennett, Nathan Kallus, Miruna Oprescu +2

We study the evaluation of a policy under best- and worst-case perturbations to a Markov decision process (MDP), using transition observations from the original MDP, whether they a…

cs.LG2024

A Reductions Approach to Risk-Sensitive Reinforcement Learning with Optimized Certainty Equivalents

Kaiwen Wang, Dawen Liang, Nathan Kallus +1

We study risk-sensitive RL where the goal is learn a history-dependent policy that optimizes some risk measure of cumulative rewards. We consider a family of risks called the optim…

cs.LG2024

Switching the Loss Reduces the Cost in Batch (Offline) Reinforcement Learning

Alex Ayoub, Kaiwen Wang, Vincent Liu +5

We propose training fitted Q-iteration with log-loss (FQI-log) for batch reinforcement learning (RL). We show that the number of samples needed to learn a near-optimal policy with…

cs.LG2024

More Benefits of Being Distributional: Second-Order Bounds for Reinforcement Learning

Kaiwen Wang, Owen Oertell, Alekh Agarwal +2

In this paper, we prove that Distributional Reinforcement Learning (DistRL), which learns the return distribution, can obtain second-order bounds in both online and offline RL in g…