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Related papers: OPAC: Opportunistic Actor-Critic

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Soft Actor-Critic (SAC) is an off-policy actor-critic deep reinforcement learning (DRL) algorithm based on maximum entropy reinforcement learning. By combining off-policy updates with an actor-critic formulation, SAC achieves…

Machine Learning · Computer Science 2019-06-11 Che Wang , Keith Ross

Off-policy actor-critic algorithms have shown strong potential in deep reinforcement learning for continuous control tasks. Their success primarily comes from leveraging pessimistic state-action value function updates, which reduce function…

Machine Learning · Computer Science 2025-08-21 Bahareh Tasdighi , Nicklas Werge , Yi-Shan Wu , Melih Kandemir

We propose WSAC (Weighted Safe Actor-Critic), a novel algorithm for Safe Offline Reinforcement Learning (RL) under functional approximation, which can robustly optimize policies to improve upon an arbitrary reference policy with limited…

Machine Learning · Computer Science 2024-11-01 Honghao Wei , Xiyue Peng , Arnob Ghosh , Xin Liu

Risk-aware Reinforcement Learning (RL) algorithms like SAC and TD3 were shown empirically to outperform their risk-neutral counterparts in a variety of continuous-action tasks. However, the theoretical basis for the pessimistic objectives…

Machine Learning · Computer Science 2024-05-27 Michal Nauman , Marek Cygan

This paper presents the first actor-critic algorithm for off-policy reinforcement learning. Our algorithm is online and incremental, and its per-time-step complexity scales linearly with the number of learned weights. Previous work on…

Machine Learning · Computer Science 2015-03-20 Thomas Degris , Martha White , Richard S. Sutton

Deep reinforcement learning (RL) algorithms can use high-capacity deep networks to learn directly from image observations. However, these high-dimensional observation spaces present a number of challenges in practice, since the policy must…

Machine Learning · Computer Science 2020-10-27 Alex X. Lee , Anusha Nagabandi , Pieter Abbeel , Sergey Levine

Policy gradient methods in actor-critic reinforcement learning (RL) have become perhaps the most promising approaches to solving continuous optimal control problems. However, the trial-and-error nature of RL and the inherent randomness…

Machine Learning · Computer Science 2024-04-19 Ruofan Wu , Junmin Zhong , Jennie Si

Actor-critic methods constitute a central paradigm in reinforcement learning (RL), coupling policy evaluation with policy improvement. While effective across many domains, these methods rely on separate actor and critic networks, which…

Machine Learning · Computer Science 2025-09-26 Donghyeon Ki , Hee-Jun Ahn , Kyungyoon Kim , Byung-Jun Lee

Model-free deep reinforcement learning (RL) algorithms have achieved tremendous success on a range of challenging tasks. However, safety concerns remain when these methods are deployed on real-world applications, necessitating risk-aware…

Machine Learning · Computer Science 2026-02-10 Alonso Granados , Jason Pacheco

We study the problem of off-policy critic evaluation in several variants of value-based off-policy actor-critic algorithms. Off-policy actor-critic algorithms require an off-policy critic evaluation step, to estimate the value of the new…

Machine Learning · Computer Science 2019-12-12 Riashat Islam , Raihan Seraj , Samin Yeasar Arnob , Doina Precup

We propose Adversarially Trained Actor Critic (ATAC), a new model-free algorithm for offline reinforcement learning (RL) under insufficient data coverage, based on the concept of relative pessimism. ATAC is designed as a two-player…

Machine Learning · Computer Science 2022-07-07 Ching-An Cheng , Tengyang Xie , Nan Jiang , Alekh Agarwal

Substantial advancements to model-based reinforcement learning algorithms have been impeded by the model-bias induced by the collected data, which generally hurts performance. Meanwhile, their inherent sample efficiency warrants utility for…

While Soft Actor-Critic (SAC) is highly effective in continuous control, its discrete counterpart (DSAC) performs poorly on challenging discrete-action domains such as Atari. Consequently, starting from DSAC, we revisit the design of…

Machine Learning · Computer Science 2026-05-13 Reza Asad , Reza Babanezhad , Sharan Vaswani

Deep Reinforcement Learning (DRL) algorithms for continuous action spaces are known to be brittle toward hyperparameters as well as \cut{being}sample inefficient. Soft Actor Critic (SAC) proposes an off-policy deep actor critic algorithm…

Machine Learning · Computer Science 2019-06-10 Patrick Nadeem Ward , Ariella Smofsky , Avishek Joey Bose

Despite definite success in deep reinforcement learning problems, actor-critic algorithms are still confronted with sample inefficiency in complex environments, particularly in tasks where efficient exploration is a bottleneck. These…

Machine Learning · Computer Science 2021-02-09 Yannis Flet-Berliac , Johan Ferret , Olivier Pietquin , Philippe Preux , Matthieu Geist

Actor-critic algorithms have become a cornerstone in reinforcement learning (RL), leveraging the strengths of both policy-based and value-based methods. Despite recent progress in understanding their statistical efficiency, no existing work…

Machine Learning · Statistics 2025-05-07 Kevin Tan , Wei Fan , Yuting Wei

Offline reinforcement learning (RL) is a promising approach for many control applications but faces challenges such as limited data coverage and value function overestimation. In this paper, we propose an implicit actor-critic (iAC)…

Machine Learning · Computer Science 2024-08-29 Vanshaj Khattar , Ming Jin

The option framework has shown great promise by automatically extracting temporally-extended sub-tasks from a long-horizon task. Methods have been proposed for concurrently learning low-level intra-option policies and high-level option…

Artificial Intelligence · Computer Science 2020-06-26 Chenghao Li , Xiaoteng Ma , Chongjie Zhang , Jun Yang , Li Xia , Qianchuan Zhao

In reinforcement learning (RL), function approximation errors are known to easily lead to the Q-value overestimations, thus greatly reducing policy performance. This paper presents a distributional soft actor-critic (DSAC) algorithm, which…

Machine Learning · Computer Science 2021-06-14 Jingliang Duan , Yang Guan , Shengbo Eben Li , Yangang Ren , Bo Cheng

Model-free deep reinforcement learning has achieved great success in many domains, such as video games, recommendation systems and robotic control tasks. In continuous control tasks, widely used policies with Gaussian distributions results…

Machine Learning · Computer Science 2023-06-05 Lingwei Peng , Hui Qian , Zhebang Shen , Chao Zhang , Fei Li