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Related papers: On Regret with Multiple Best Arms

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We consider a novel stochastic multi-armed bandit setting, where playing an arm makes it unavailable for a fixed number of time slots thereafter. This models situations where reusing an arm too often is undesirable (e.g. making the same…

Machine Learning · Computer Science 2024-07-31 Soumya Basu , Rajat Sen , Sujay Sanghavi , Sanjay Shakkottai

We investigate the problem of stochastic, combinatorial multi-armed bandits where the learner only has access to bandit feedback and the reward function can be non-linear. We provide a general framework for adapting discrete offline…

Machine Learning · Computer Science 2023-10-13 Guanyu Nie , Yididiya Y Nadew , Yanhui Zhu , Vaneet Aggarwal , Christopher John Quinn

We consider linear stochastic bandits where the set of actions is an ellipsoid. We provide the first known minimax optimal algorithm for this problem. We first derive a novel information-theoretic lower bound on the regret of any algorithm,…

Machine Learning · Statistics 2025-02-25 Raymond Zhang , Hedi Hadiji , Richard Combes

Decision making under uncertain environments in the maximization of expected reward while minimizing its risk is one of the ubiquitous problems in many subjects. Here, we introduce a novel problem setting in stochastic bandit optimization…

Machine Learning · Computer Science 2025-10-27 Shunta Nonaga , Koji Tabata , Yuta Mizuno , Tamiki Komatsuzaki

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

Multi-armed bandit problems are the predominant theoretical model of exploration-exploitation tradeoffs in learning, and they have countless applications ranging from medical trials, to communication networks, to Web search and advertising.…

Data Structures and Algorithms · Computer Science 2017-09-06 Ashwinkumar Badanidiyuru , Robert Kleinberg , Aleksandrs Slivkins

We discuss a multiple-play multi-armed bandit (MAB) problem in which several arms are selected at each round. Recently, Thompson sampling (TS), a randomized algorithm with a Bayesian spirit, has attracted much attention for its empirically…

Machine Learning · Statistics 2019-03-22 Junpei Komiyama , Junya Honda , Hiroshi Nakagawa

We revisit the problem of online learning with sleeping experts/bandits: in each time step, only a subset of the actions are available for the algorithm to choose from (and learn about). The work of Kleinberg et al. (2010) showed that there…

Machine Learning · Computer Science 2021-04-27 Ehsan Emamjomeh-Zadeh , Chen-Yu Wei , Haipeng Luo , David Kempe

We consider the classical multi-armed bandit problem, but with strategic arms. In this context, each arm is characterized by a bounded support reward distribution and strategically aims to maximize its own utility by potentially retaining a…

Machine Learning · Computer Science 2025-01-28 Ahmed Ben Yahmed , Clément Calauzènes , Vianney Perchet

One of the key drivers of complexity in the classical (stochastic) multi-armed bandit (MAB) problem is the difference between mean rewards in the top two arms, also known as the instance gap. The celebrated Upper Confidence Bound (UCB)…

Machine Learning · Computer Science 2021-10-27 Anand Kalvit , Assaf Zeevi

An adversarial bandit problem with memory constraints is studied where only the statistics of a subset of arms can be stored. A hierarchical learning policy that requires only a sublinear order of memory space in terms of the number of arms…

Machine Learning · Computer Science 2021-05-12 Xiao Xu , Qing Zhao

This work addresses a version of the two-armed Bernoulli bandit problem where the sum of the means of the arms is one (the symmetric two-armed Bernoulli bandit). In a regime where the gap between these means goes to zero as the number of…

Machine Learning · Computer Science 2023-07-18 Vladimir A. Kobzar , Robert V. Kohn

We develop the first general semi-bandit algorithm that simultaneously achieves $\mathcal{O}(\log T)$ regret for stochastic environments and $\mathcal{O}(\sqrt{T})$ regret for adversarial environments without knowledge of the regime or the…

Machine Learning · Computer Science 2019-09-27 Julian Zimmert , Haipeng Luo , Chen-Yu Wei

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 small-loss bounds for adversarial multi-armed bandits with graph feedback, that is, adaptive regret bounds that depend on the loss of the best arm or related quantities, instead of the total number of rounds. We derive the first…

Machine Learning · Computer Science 2020-06-24 Chung-Wei Lee , Haipeng Luo , Mengxiao Zhang

We investigate the regret-minimisation problem in a multi-armed bandit setting with arbitrary corruptions. Similar to the classical setup, the agent receives rewards generated independently from the distribution of the arm chosen at each…

Machine Learning · Statistics 2023-09-29 Shubhada Agrawal , Timothée Mathieu , Debabrota Basu , Odalric-Ambrym Maillard

In this paper we propose a novel experimental design-based algorithm to minimize regret in online stochastic linear and combinatorial bandits. While existing literature tends to focus on optimism-based algorithms--which have been shown to…

Machine Learning · Computer Science 2021-03-02 Andrew Wagenmaker , Julian Katz-Samuels , Kevin Jamieson

We consider the infinitely many-armed bandit problem with rotting rewards, where the mean reward of an arm decreases at each pull of the arm according to an arbitrary trend with maximum rotting rate $\varrho=o(1)$. We show that this…

Machine Learning · Computer Science 2023-12-19 Jung-hun Kim , Milan Vojnovic , Se-Young Yun

We propose an algorithm for stochastic and adversarial multiarmed bandits with switching costs, where the algorithm pays a price $\lambda$ every time it switches the arm being played. Our algorithm is based on adaptation of the Tsallis-INF…

Machine Learning · Computer Science 2021-02-22 Chloé Rouyer , Yevgeny Seldin , Nicolò Cesa-Bianchi

We study a security threat to adversarial multi-armed bandits, in which an attacker perturbs the loss or reward signal to control the behavior of the victim bandit player. We show that the attacker is able to mislead any no-regret…

Machine Learning · Computer Science 2023-01-31 Yuzhe Ma , Zhijin Zhou