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Related papers: Robust Best-arm Identification in Linear Bandits

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We study the problem of identifying the best arm in a multi-armed bandit environment when each arm is a time-homogeneous and ergodic discrete-time Markov process on a common, finite state space. The state evolution on each arm is governed…

Machine Learning · Statistics 2022-03-30 P. N. Karthik , Kota Srinivas Reddy , Vincent Y. F. Tan

The Multi-Armed Bandits (MAB) framework highlights the tension between acquiring new knowledge (Exploration) and leveraging available knowledge (Exploitation). In the classical MAB problem, a decision maker must choose an arm at each time…

Machine Learning · Statistics 2017-11-03 Nir Levine , Koby Crammer , Shie Mannor

We study best-arm identification (BAI) in the fixed-budget setting. Adaptive allocations based on upper confidence bounds (UCBs), such as UCBE, are known to work well in BAI. However, it is well-known that its optimal regret is…

Machine Learning · Computer Science 2024-10-24 Rong J. B. Zhu , Yanqi Qiu

We propose a new problem setting to study the sequential interactions between a recommender system and a user. Instead of assuming the user is omniscient, static, and explicit, as the classical practice does, we sketch a more realistic user…

Machine Learning · Computer Science 2021-10-08 Fan Yao , Chuanhao Li , Denis Nekipelov , Hongning Wang , Haifeng Xu

The best arm identification problem (BEST-1-ARM) is the most basic pure exploration problem in stochastic multi-armed bandits. The problem has a long history and attracted significant attention for the last decade. However, we do not yet…

Machine Learning · Computer Science 2016-05-30 Lijie Chen , Jian Li

Best arm identification (or, pure exploration) in multi-armed bandits is a fundamental problem in machine learning. In this paper we study the distributed version of this problem where we have multiple agents, and they want to learn the…

Machine Learning · Computer Science 2019-09-02 Chao Tao , Qin Zhang , Yuan Zhou

We test whether LLMs show robust decision biases. Treating models as participants in two-arm bandits, we ran 20000 trials per condition across four decoding configurations. Under symmetric rewards, models amplified positional order into…

Artificial Intelligence · Computer Science 2026-03-10 Haomiaomiao Wang , Tomás E Ward , Lili Zhang

Lai and Robbins (1985) and Lai (1987) provided efficient parametric solutions to the multi-armed bandit problem, showing that arm allocation via upper confidence bounds (UCB) achieves minimum regret. These bounds are constructed from the…

Statistics Theory · Mathematics 2019-01-17 Hock Peng Chan

In the classic Bayesian restless multi-armed bandit (RMAB) problem, there are $N$ arms, with rewards on all arms evolving at each time as Markov chains with known parameters. A player seeks to activate $K \geq 1$ arms at each time in order…

Optimization and Control · Mathematics 2010-11-23 Wenhan Dai , Yi Gai , Bhaskar Krishnamachari , Qing Zhao

Restless multi-armed bandits (RMAB) play a central role in modeling sequential decision making problems under an instantaneous activation constraint that at most B arms can be activated at any decision epoch. Each restless arm is endowed…

Machine Learning · Computer Science 2024-05-03 Guojun Xiong , Jian Li

The multi-armed bandit (MAB) problem models a decision-maker that optimizes its actions based on current and acquired new knowledge to maximize its reward. This type of online decision is prominent in many procedures of Brain-Computer…

Artificial Intelligence · Computer Science 2022-11-10 Frida Heskebeck , Carolina Bergeling , Bo Bernhardsson

We consider a multi-armed bandit problem motivated by situations where only the extreme values, as opposed to expected values in the classical bandit setting, are of interest. We propose distribution free algorithms using robust statistics…

Machine Learning · Statistics 2021-09-10 Sujay Bhatt , Ping Li , Gennady Samorodnitsky

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 study the Pareto Set Identification (PSI) problem in a structured multi-output linear bandit model. In this setting, each arm is associated a feature vector belonging to $\mathbb{R}^h$, and its mean vector in $\mathbb{R}^d$ linearly…

Machine Learning · Statistics 2025-07-08 Cyrille Kone , Emilie Kaufmann , Laura Richert

Most algorithms for the multi-armed bandit problem in reinforcement learning aimed to maximize the expected reward, which are thus useful in searching the optimized candidate with the highest reward (function value) for diverse applications…

Machine Learning · Computer Science 2022-01-03 Bin Chong , Yingguang Yang , Zi-Le Wang , Hang Xing , Zhirong Liu

This paper studies bandit problems where an agent has access to offline data that might be utilized to potentially improve the estimation of each arm's reward distribution. A major obstacle in this setting is the existence of compound…

Machine Learning · Computer Science 2023-12-21 Wen Huang , Xintao Wu

This paper introduces a general framework for risk-sensitive bandits that integrates the notions of risk-sensitive objectives by adopting a rich class of distortion riskmetrics. The introduced framework subsumes the various existing…

Machine Learning · Statistics 2025-03-13 Meltem Tatlı , Arpan Mukherjee , Prashanth L. A. , Karthikeyan Shanmugam , Ali Tajer

We consider a stochastic multi-armed bandit setting and study the problem of constrained regret minimization over a given time horizon. Each arm is associated with an unknown, possibly multi-dimensional distribution, and the merit of an arm…

Machine Learning · Computer Science 2023-01-05 Anmol Kagrecha , Jayakrishnan Nair , Krishna Jagannathan

The multi-armed bandit (MAB) model is one of the most classical models to study decision-making in an uncertain environment. In this model, a player chooses one of $K$ possible arms of a bandit machine to play at each time step, where the…

Machine Learning · Computer Science 2023-06-13 Bo Li , Chi Ho Yeung

In this paper, we consider a multi-armed bandit (MAB) instance and study how to identify the best arm when arm commands are conveyed from a central learner to a distributed agent over a discrete memoryless channel (DMC). Depending on the…

Information Theory · Computer Science 2026-04-03 Merve Karakas , Osama Hanna , Lin F. Yang , Christina Fragouli