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Related papers: Unimodal Bandits without Smoothness

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We study the multi-armed bandit problem with adversarially chosen delays in the Best-of-Both-Worlds (BoBW) framework, which aims to achieve near-optimal performance in both stochastic and adversarial environments. While prior work has made…

Machine Learning · Computer Science 2025-10-21 Ofir Schlisselberg , Tal Lancewicki , Peter Auer , Yishay Mansour

Motivated by modern applications, such as online advertisement and recommender systems, we study the top-$k$ extreme contextual bandits problem, where the total number of arms can be enormous, and the learner is allowed to select $k$ arms…

Machine Learning · Statistics 2021-02-17 Rajat Sen , Alexander Rakhlin , Lexing Ying , Rahul Kidambi , Dean Foster , Daniel Hill , Inderjit Dhillon

This paper investigates the problem of best arm identification in $\textit{contaminated}$ stochastic multi-arm bandits. In this setting, the rewards obtained from any arm are replaced by samples from an adversarial model with probability…

Machine Learning · Computer Science 2021-11-16 Arpan Mukherjee , Ali Tajer , Pin-Yu Chen , Payel Das

Stochastic bandit algorithms are usually analyzed under a mean-reward criterion, yet many problems favor arms with strong upper-tail performance, which we study herein. For a fixed miscoverage level \(\alpha\), the natural upper-tail target…

Machine Learning · Computer Science 2026-05-11 Chengyu Du , Mengfan Xu

Generalized linear bandits have been extensively studied due to their broad applicability in real-world online decision-making problems. However, these methods typically assume that the expected reward function is known to the users, an…

Machine Learning · Statistics 2026-02-10 Yue Kang , Mingshuo Liu , Bongsoo Yi , Jing Lyu , Zhi Zhang , Doudou Zhou , Yao Li

We study a variant of the stochastic multi-armed bandit (MAB) problem in which the rewards are corrupted. In this framework, motivated by privacy preservation in online recommender systems, the goal is to maximize the sum of the…

Machine Learning · Computer Science 2017-11-06 Pratik Gajane , Tanguy Urvoy , Emilie Kaufmann

We analyze the $K$-armed bandit problem where the reward for each arm is a noisy realization based on an observed context under mild nonparametric assumptions. We attain tight results for top-arm identification and a sublinear regret of…

Machine Learning · Computer Science 2018-01-08 Melody Y. Guan , Heinrich Jiang

We consider a budget-constrained bandit problem where each arm pull incurs a random cost, and yields a random reward in return. The objective is to maximize the total expected reward under a budget constraint on the total cost. The model is…

Machine Learning · Computer Science 2020-03-03 Semih Cayci , Atilla Eryilmaz , R. Srikant

The Greedy algorithm is the simplest heuristic in sequential decision problem that carelessly takes the locally optimal choice at each round, disregarding any advantages of exploring and/or information gathering. Theoretically, it is known…

Machine Learning · Computer Science 2021-01-05 Matthieu Jedor , Jonathan Louëdec , Vianney Perchet

Upper Confidence Bound (UCB) algorithms are a widely-used class of sequential algorithms for the $K$-armed bandit problem. Despite extensive research over the past decades aimed at understanding their asymptotic and (near) minimax…

Statistics Theory · Mathematics 2024-12-10 Qiyang Han , Koulik Khamaru , Cun-Hui Zhang

This paper proposes a variant of multiple-play stochastic bandits tailored to resource allocation problems arising from LLM applications, edge intelligence, etc. The model is composed of $M$ arms and $K$ plays. Each arm has a stochastic…

Artificial Intelligence · Computer Science 2025-12-29 Hong Xie , Haoran Gu , Yanying Huang , Tao Tan , Defu Lian

We consider stochastic sequential learning problems where the learner can observe the \textit{average reward of several actions}. Such a setting is interesting in many applications involving monitoring and surveillance, where the set of the…

Machine Learning · Computer Science 2015-06-22 Manjesh Kumar Hanawal , Venkatesh Saligrama , Michal Valko , R\' emi Munos

Designing efficient general-purpose contextual bandit algorithms that work with large -- or even continuous -- action spaces would facilitate application to important scenarios such as information retrieval, recommendation systems, and…

Machine Learning · Computer Science 2022-07-14 Yinglun Zhu , Paul Mineiro

In stochastic multi-armed bandits, the reward distribution of each arm is assumed to be stationary. This assumption is often violated in practice (e.g., in recommendation systems), where the reward of an arm may change whenever is selected,…

Machine Learning · Statistics 2020-05-12 Julien Seznec , Andrea Locatelli , Alexandra Carpentier , Alessandro Lazaric , Michal Valko

This paper studies batched bandit learning problems for nondegenerate functions. We introduce an algorithm that solves the batched bandit problem for nondegenerate functions near-optimally. More specifically, we introduce an algorithm,…

Machine Learning · Statistics 2025-04-09 Yu Liu , Yunlu Shu , Tianyu Wang

This paper considers the multi-armed bandit (MAB) problem and provides a new best-of-both-worlds (BOBW) algorithm that works nearly optimally in both stochastic and adversarial settings. In stochastic settings, some existing BOBW algorithms…

Machine Learning · Computer Science 2022-06-15 Shinji Ito , Taira Tsuchiya , Junya Honda

We consider the classic online learning and stochastic multi-armed bandit (MAB) problems, when at each step, the online policy can probe and find out which of a small number ($k$) of choices has better reward (or loss) before making its…

Data Structures and Algorithms · Computer Science 2022-11-08 Aditya Bhaskara , Sreenivas Gollapudi , Sungjin Im , Kostas Kollias , Kamesh Munagala

We study, to the best of our knowledge, the first Bayesian algorithm for unimodal Multi-Armed Bandit (MAB) problems with graph structure. In this setting, each arm corresponds to a node of a graph and each edge provides a relationship,…

Machine Learning · Computer Science 2016-11-23 Stefano Paladino , Francesco Trovò , Marcello Restelli , Nicola Gatti

We study an infinite-armed bandit problem where actions' mean rewards are initially sampled from a reservoir distribution. Most prior works in this setting focused on stationary rewards (Berry et al., 1997; Wang et al., 2008; Bonald and…

Machine Learning · Computer Science 2025-02-04 Joe Suk , Jung-hun Kim

The objective of canonical multi-armed bandits is to identify and repeatedly select an arm with the largest reward, often in the form of the expected value of the arm's probability distribution. Such a utilitarian perspective and focus on…

Machine Learning · Statistics 2025-05-01 Meltem Tatlı , Arpan Mukherjee , Prashanth L. A. , Karthikeyan Shanmugam , Ali Tajer