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Related papers: UCB algorithms for multi-armed bandits: Precise re…

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We study fine-grained gap-dependent regret bounds for model-free reinforcement learning in episodic tabular Markov Decision Processes. Existing model-free algorithms achieve minimax worst-case regret, but their gap-dependent bounds remain…

Machine Learning · Statistics 2025-10-09 Haochen Zhang , Zhong Zheng , Lingzhou Xue

We study an important variant of the stochastic multi-armed bandit (MAB) problem, which takes penalization into consideration. Instead of directly maximizing cumulative expected reward, we need to balance between the total reward and…

Machine Learning · Statistics 2022-11-16 Guanhua Fang , Ping Li , Gennady Samorodnitsky

We study the $\textit{single-index bandit}$ problem, where rewards depend on an unknown one-dimensional projection of high-dimensional contexts through an unknown reward function. This model extends linear and generalized linear bandits to…

Machine Learning · Statistics 2026-05-12 Devdan Dey , Sujoy Bhore , Avishek Ghosh

We study the linear contextual bandit problem with finite action sets. When the problem dimension is $d$, the time horizon is $T$, and there are $n \leq 2^{d/2}$ candidate actions per time period, we (1) show that the minimax expected…

Machine Learning · Statistics 2020-08-20 Yingkai Li , Yining Wang , Yuan Zhou

We study the distribution of regret in stochastic multi-armed bandits and episodic reinforcement learning through a unified framework. We formalize a distributional regret bound as a probabilistic guarantee that holds uniformly over all…

Machine Learning · Computer Science 2026-05-08 Harin Lee , Min-hwan Oh

We consider the setup of stochastic multi-armed bandits in the case when reward distributions are piecewise i.i.d. and bounded with unknown changepoints. We focus on the case when changes happen simultaneously on all arms, and in stark…

Machine Learning · Computer Science 2019-06-10 Subhojyoti Mukherjee , Odalric-Ambrym Maillard

The upper confidence bound (UCB) policy is recognized as an order-optimal solution for the classical total-reward bandit problem. While similar UCB-based approaches have been applied to the max bandit problem, which aims to maximize the…

Machine Learning · Statistics 2024-11-04 Nobuaki Kikkawa , Hiroshi Ohno

By leveraging the representation power of deep neural networks, neural upper confidence bound (UCB) algorithms have shown success in contextual bandits. To further balance the exploration and exploitation, we propose…

Machine Learning · Computer Science 2025-03-12 Ha Manh Bui , Enrique Mallada , Anqi Liu

The multi-armed bandit (MAB) problem is a classical problem that models sequential decision-making under uncertainty in reinforcement learning. In this study, we propose a new generalized upper confidence bound (UCB) algorithm (GWA-UCB1) by…

Machine Learning · Computer Science 2023-08-29 Nobuhito Manome , Shuji Shinohara , Ung-il Chung

We consider stochastic multi-armed bandit problems where the expected reward is a Lipschitz function of the arm, and where the set of arms is either discrete or continuous. For discrete Lipschitz bandits, we derive asymptotic problem…

Machine Learning · Computer Science 2014-05-20 Stefan Magureanu , Richard Combes , Alexandre Proutiere

During online decision making in Multi-Armed Bandits (MAB), one needs to conduct inference on the true mean reward of each arm based on data collected so far at each step. However, since the arms are adaptively selected--thereby yielding…

Machine Learning · Computer Science 2021-06-29 Maria Dimakopoulou , Zhimei Ren , Zhengyuan Zhou

Motivated by real-world applications that necessitate responsible experimentation, we introduce the problem of best arm identification (BAI) with minimal regret. This innovative variant of the multi-armed bandit problem elegantly…

Machine Learning · Computer Science 2024-09-30 Junwen Yang , Vincent Y. F. Tan , Tianyuan Jin

We introduce Conformal Bandits, a novel framework integrating Conformal Prediction (CP) into bandit problems, a classic paradigm for sequential decision-making under uncertainty. Traditional regret-minimisation bandit strategies like…

Machine Learning · Computer Science 2025-12-11 Simone Cuonzo , Nina Deliu

Multiplayer bandits have recently been extensively studied because of their application to cognitive radio networks. While the literature mostly considers synchronous players, radio networks (e.g. for IoT) tend to have asynchronous devices.…

Machine Learning · Computer Science 2023-06-01 Hugo Richard , Etienne Boursier , Vianney Perchet

This paper is devoted to regret lower bounds in the classical model of stochastic multi-armed bandit. A well-known result of Lai and Robbins, which has then been extended by Burnetas and Katehakis, has established the presence of a…

Machine Learning · Statistics 2011-12-19 Antoine Salomon , Jean-Yves Audibert , Issam El Alaoui

We study the corrupted bandit problem, i.e. a stochastic multi-armed bandit problem with $k$ unknown reward distributions, which are heavy-tailed and corrupted by a history-independent adversary or Nature. To be specific, the reward…

Machine Learning · Computer Science 2023-03-22 Debabrota Basu , Odalric-Ambrym Maillard , Timothée Mathieu

We present differentially private algorithms for the stochastic Multi-Armed Bandit (MAB) problem. This is a problem for applications such as adaptive clinical trials, experiment design, and user-targeted advertising where private…

Machine Learning · Statistics 2015-11-30 Aristide Tossou , Christos Dimitrakakis

We study the impact of sharing exploration in multi-armed bandits in a grouped setting where a set of groups have overlapping feasible action sets [Baek and Farias '24]. In this grouped bandit setting, groups share reward observations, and…

Machine Learning · Computer Science 2025-06-13 Moïse Blanchard , Vineet Goyal

Motivated by models of human decision making proposed to explain commonly observed deviations from conventional expected value preferences, we formulate two stochastic multi-armed bandit problems with distorted probabilities on the reward…

Machine Learning · Computer Science 2023-11-01 Ravi Kumar Kolla , Prashanth L. A. , Aditya Gopalan , Krishna Jagannathan , Michael Fu , Steve Marcus

We study the Pareto frontier of two archetypal objectives in multi-armed bandits, namely, regret minimization (RM) and best arm identification (BAI) with a fixed horizon. It is folklore that the balance between exploitation and exploration…

Machine Learning · Computer Science 2023-06-12 Zixin Zhong , Wang Chi Cheung , Vincent Y. F. Tan