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20222026
most citedOptimism in Face of a Context: Regret Guarantees for Stochastic Contextual MDP

1 citations · 2 across the 9 of their papers we have counts for

collaborators

11 papers

cs.LG2026

Vanilla Policy Optimization Is Both Optimal and Differentially Private for Stochastic Contextual Bandits

Idan Attias, Orin Levy, Alexander Ryabchenko +2

Can vanilla policy optimization explore enough to achieve near-optimal regret in stochastic contextual bandits? We show that standard exponential policy updates driven by offline r…

cs.LG2026

Near-Optimal Regret for Policy Optimization in Contextual MDPs with General Offline Function Approximation

Orin Levy, Aviv Rosenberg, Alon Cohen +1

We introduce \texttt{OPO-CMDP}, the first policy optimization algorithm for stochastic Contextual Markov Decision Process (CMDPs) under general offline function approximation. Our…

cs.LG2026

Optimal Regret for Policy Optimization in Contextual Bandits

Orin Levy, Yishay Mansour

We present the first high-probability optimal regret bound for a policy optimization technique applied to the problem of stochastic contextual multi-armed bandit (CMAB) with genera…

cs.LG2026

The Horizon Threshold in Cooperative Multi-Agent Reward-Free Exploration

Idan Barnea, Orin Levy, Yishay Mansour

We study cooperative multi-agent reinforcement learning in the setting of reward-free exploration, where multiple agents jointly explore an unknown MDP in order to learn its dynami…

cs.LG2025

Regret Bounds for Adversarial Contextual Bandits with General Function Approximation and Delayed Feedback

Orin Levy, Liad Erez, Alon Cohen +1

We present regret minimization algorithms for the contextual multi-armed bandit (CMAB) problem over actions in the presence of delayed feedback, a scenario where loss observati…

cs.LG2024

Online Weighted Paging with Unknown Weights

Orin Levy, Noam Touitou, Aviv Rosenberg

Online paging is a fundamental problem in the field of online algorithms, in which one maintains a cache of slots as requests for fetching pages arrive online. In the weighted…

cs.LG2024

Batch Ensemble for Variance Dependent Regret in Stochastic Bandits

Asaf Cassel, Orin Levy, Yishay Mansour

Efficiently trading off exploration and exploitation is one of the key challenges in online Reinforcement Learning (RL). Most works achieve this by carefully estimating the model u…

cs.LG2023

Efficient Rate Optimal Regret for Adversarial Contextual MDPs Using Online Function Approximation

Orin Levy, Alon Cohen, Asaf Cassel +1

We present the OMG-CMDP! algorithm for regret minimization in adversarial Contextual MDPs. The algorithm operates under the minimal assumptions of realizable function class and acc…

cs.LG2022

Eluder-based Regret for Stochastic Contextual MDPs

Orin Levy, Asaf Cassel, Alon Cohen +1

We present the E-UCRL algorithm for regret minimization in Stochastic Contextual Markov Decision Processes (CMDPs). The algorithm operates under the minimal assumptions of real…

cs.LG2022★ 1 cited

Optimism in Face of a Context: Regret Guarantees for Stochastic Contextual MDP

Orin Levy, Yishay Mansour

We present regret minimization algorithms for stochastic contextual MDPs under minimum reachability assumption, using an access to an offline least square regression oracle. We ana…

cs.LG2022★ 1 cited

Learning Efficiently Function Approximation for Contextual MDP

Orin Levy, Yishay Mansour

We study learning contextual MDPs using a function approximation for both the rewards and the dynamics. We consider both the case that the dynamics dependent or independent of the…