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Related papers: Is Pessimism Provably Efficient for Offline RL?

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Recent theoretical work studies sample-efficient reinforcement learning (RL) extensively in two settings: learning interactively in the environment (online RL), or learning from an offline dataset (offline RL). However, existing algorithms…

Machine Learning · Computer Science 2022-02-14 Tengyang Xie , Nan Jiang , Huan Wang , Caiming Xiong , Yu Bai

Constraint-based offline reinforcement learning (RL) involves policy constraints or imposing penalties on the value function to mitigate overestimation errors caused by distributional shift. This paper focuses on a limitation in existing…

Machine Learning · Computer Science 2024-10-25 Junghyuk Yeom , Yonghyeon Jo , Jungmo Kim , Sanghyeon Lee , Seungyul Han

Transfer reinforcement learning aims to derive a near-optimal policy for a target environment with limited data by leveraging abundant data from related source domains. However, it faces two key challenges: the lack of performance…

Machine Learning · Computer Science 2025-05-30 Chi Zhang , Ziying Jia , George K. Atia , Sihong He , Yue Wang

In offline reinforcement learning (offline RL), one of the main challenges is to deal with the distributional shift between the learning policy and the given dataset. To address this problem, recent offline RL methods attempt to introduce…

Machine Learning · Computer Science 2021-11-16 Jianhao Wang , Wenzhe Li , Haozhe Jiang , Guangxiang Zhu , Siyuan Li , Chongjie Zhang

Reinforcement learning (RL) is a fundamental framework for sequential decision-making, in which an agent learns an optimal policy through interactions with an unknown environment. In settings with function approximation, many existing RL…

Machine Learning · Computer Science 2026-05-05 Ruiquan Huang , Donghao Li , Yingbin Liang , Jing Yang

Inverse reinforcement learning (IRL) addresses the problem of recovering a task description given a demonstration of the optimal policy used to solve such a task. The optimal policy is usually provided by an expert or teacher, making IRL…

Machine Learning · Computer Science 2012-02-09 Héctor Ratia , Luis Montesano , Ruben Martinez-Cantin

The proximal policy optimization (PPO) algorithm stands as one of the most prosperous methods in the field of reinforcement learning (RL). Despite its success, the theoretical understanding of PPO remains deficient. Specifically, it is…

Machine Learning · Computer Science 2023-06-09 Han Zhong , Tong Zhang

Offline reinforcement learning (RL) represents a significant shift in RL research, allowing agents to learn from pre-collected datasets without further interaction with the environment. A key, yet underexplored, challenge in offline RL is…

Machine Learning · Computer Science 2025-02-27 Yiqin Yang , Quanwei Wang , Chenghao Li , Hao Hu , Chengjie Wu , Yuhua Jiang , Dianyu Zhong , Ziyou Zhang , Qianchuan Zhao , Chongjie Zhang , Xu Bo

Offline-to-online reinforcement learning (RL) leverages both pre-trained offline policies and online policies trained for downstream tasks, aiming to improve data efficiency and accelerate performance enhancement. An existing approach,…

Machine Learning · Computer Science 2024-11-01 JaeYoon Kim , Junyu Xuan , Christy Liang , Farookh Hussain

In real-world scenarios, datasets collected from randomized experiments are often constrained by size, due to limitations in time and budget. As a result, leveraging large observational datasets becomes a more attractive option for…

Machine Learning · Statistics 2024-03-19 Danyang Wang , Chengchun Shi , Shikai Luo , Will Wei Sun

Offline reinforcement learning (RL) enables data-efficient and safe policy learning without online exploration, but its performance often degrades under distribution shift. The learned policy may visit out-of-distribution state-action pairs…

Artificial Intelligence · Computer Science 2026-03-17 Hongqiang Lin , Zhenghui Fu , Weihao Tang , Pengfei Wang , Yiding Sun , Qixian Huang , Dongxu Zhang

Reinforcement learning (RL) problems are fundamental in online decision-making and have been instrumental in finding an optimal policy for Markov decision processes (MDPs). Function approximations are usually deployed to handle large or…

Machine Learning · Computer Science 2025-05-20 Jiashuo Jiang , Yiming Zong , Yinyu Ye

Offline reinforcement learning (RL) shows promise of applying RL to real-world problems by effectively utilizing previously collected data. Most existing offline RL algorithms use regularization or constraints to suppress extrapolation…

Machine Learning · Computer Science 2021-10-20 Xiaoteng Ma , Yiqin Yang , Hao Hu , Qihan Liu , Jun Yang , Chongjie Zhang , Qianchuan Zhao , Bin Liang

We study offline learning in KL-regularized two-player zero-sum games, where policies are optimized with respect to a fixed reference policy through KL regularization. Prior work relies on pessimistic value estimation to handle distribution…

Computer Science and Game Theory · Computer Science 2026-05-11 Yuheng Zhang , Claire Chen , Nan Jiang

Sample efficiency and exploration remain major challenges in online reinforcement learning (RL). A powerful approach that can be applied to address these issues is the inclusion of offline data, such as prior trajectories from a human…

Machine Learning · Computer Science 2023-06-01 Philip J. Ball , Laura Smith , Ilya Kostrikov , Sergey Levine

Offline policy learning is aimed at learning decision-making policies using existing datasets of trajectories without collecting additional data. The primary motivation for using reinforcement learning (RL) instead of supervised learning…

Reinforcement Learning (RL) has demonstrated tremendous empirical success across numerous challenging domains. However, we lack a strong theoretical understanding of the statistical complexity of RL in environments with large state spaces,…

Machine Learning · Computer Science 2025-06-03 Gene Li

We study risk-aware offline policy learning, aiming to learn a decision rule from logged data that is optimal under general risk criteria. This problem is crucial in high-stakes domains where online interaction is infeasible and adverse…

Machine Learning · Statistics 2026-05-18 Yilong Wan , Yuqiang Li , Xianyi Wu

We consider offline Reinforcement Learning (RL), where the agent does not interact with the environment and must rely on offline data collected using a behavior policy. Previous works provide policy evaluation guarantees when the target…

Machine Learning · Computer Science 2023-05-26 Xumei Xi , Christina Lee Yu , Yudong Chen

We consider online reinforcement learning (RL) in episodic Markov decision processes (MDPs) under the linear $q^\pi$-realizability assumption, where it is assumed that the action-values of all policies can be expressed as linear functions…

Machine Learning · Computer Science 2023-12-21 Gellért Weisz , András György , Csaba Szepesvári