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Related papers: Variance-Dependent Best Arm Identification

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Motivated by recursive learning in Markov Decision Processes, this paper studies best-arm identification in bandit problems where each arm's reward is drawn from a multinomial distribution with a known support. We compare the performance {…

Machine Learning · Computer Science 2025-02-19 Mehrasa Ahmadipour , élise Crepon , Aurélien Garivier

We study the fixed-budget best-arm identification (BAI) problem in non-stationary linear bandits. Concretely, given a fixed time budget $T\in \mathbb{N}$, finite arm set $\mathcal{X} \subset \mathbb{R}^d$, and a potentially adversarial…

Machine Learning · Statistics 2026-03-12 Leo Maynard-Zhang , Zhihan Xiong , Kevin Jamieson , Maryam Fazel

We consider a variant of the best arm identification task in stochastic multi-armed bandits. Motivated by risk-averse decision-making problems, our goal is to identify a set of $m$ arms with the highest $\tau$-quantile values within a fixed…

Machine Learning · Computer Science 2023-02-22 Mengyan Zhang , Cheng Soon Ong

We address the problem of best arm identification (BAI) with a fixed budget for two-armed Gaussian bandits. In BAI, given multiple arms, we aim to find the best arm, an arm with the highest expected reward, through an adaptive experiment.…

Machine Learning · Computer Science 2024-03-19 Masahiro Kato

The best arm identification problem in the multi-armed bandit setting is an excellent model of many real-world decision-making problems, yet it fails to capture the fact that in the real-world, safety constraints often must be met while…

Machine Learning · Computer Science 2021-11-25 Zhenlin Wang , Andrew Wagenmaker , Kevin Jamieson

The pure-exploration problem in stochastic multi-armed bandits aims to find one or more arms with the largest (or near largest) means. Examples include finding an {\epsilon}-good arm, best-arm identification, top-k arm identification, and…

Machine Learning · Statistics 2020-09-14 Blake Mason , Lalit Jain , Ardhendu Tripathy , Robert Nowak

We present an efficient and generalised procedure to accurately identify the best (or near best) performing algorithm for each sub-task in a multi-problem domain. Our approach treats this as a set of best arm identification problems for…

Machine Learning · Computer Science 2026-04-22 Matthew Stephenson , Alex Newcombe , Eric Piette , Dennis Soemers

We consider a restless multi-armed bandit in which each arm can be in one of two states. When an arm is sampled, the state of the arm is not available to the sampler. Instead, a binary signal with a known randomness that depends on the…

Systems and Control · Computer Science 2017-12-20 Rahul Meshram , D. Manjunath , Aditya Gopalan

Given a vector of probability distributions, or arms, each of which can be sampled independently, we consider the problem of identifying the partition to which this vector belongs from a finitely partitioned universe of such vector of…

Machine Learning · Computer Science 2019-02-06 Sandeep Juneja , Subhashini Krishnasamy

We introduce a new graphical bilinear bandit problem where a learner (or a \emph{central entity}) allocates arms to the nodes of a graph and observes for each edge a noisy bilinear reward representing the interaction between the two end…

Machine Learning · Computer Science 2021-06-14 Geovani Rizk , Albert Thomas , Igor Colin , Rida Laraki , Yann Chevaleyre

We study the problem of minimizing gap-dependent regret for single-pass streaming stochastic multi-armed bandits (MAB). In this problem, the $n$ arms are present in a stream, and at most $m<n$ arms and their statistics can be stored in the…

Machine Learning · Computer Science 2025-03-05 Zichun Ye , Chihao Zhang , Jiahao Zhao

We study the stochastic multi-armed bandit problem with non-equivalent multiple plays where, at each step, an agent chooses not only a set of arms, but also their order, which influences reward distribution. In several problem formulations…

Machine Learning · Computer Science 2015-07-20 Aleksandr Vorobev , Gleb Gusev

Top-$2$ methods have become popular in solving the best arm identification (BAI) problem. The best arm, or the arm with the largest mean amongst finitely many, is identified through an algorithm that at any sequential step independently…

Machine Learning · Computer Science 2024-12-17 Agniv Bandyopadhyay , Sandeep Juneja , Shubhada Agrawal

In this paper we consider the contextual multi-armed bandit problem for linear payoffs under a risk-averse criterion. At each round, contexts are revealed for each arm, and the decision maker chooses one arm to pull and receives the…

Machine Learning · Computer Science 2022-06-28 Yifan Lin , Yuhao Wang , Enlu Zhou

We consider the problem of identifying any $k$ out of the best $m$ arms in an $n$-armed stochastic multi-armed bandit. Framed in the PAC setting, this particular problem generalises both the problem of `best subset selection' and that of…

Machine Learning · Computer Science 2019-01-25 Arghya Roy Chaudhuri , Shivaram Kalyanakrishnan

We consider a multi-armed bandit problem where the decision maker can explore and exploit different arms at every round. The exploited arm adds to the decision maker's cumulative reward (without necessarily observing the reward) while the…

Machine Learning · Computer Science 2012-07-03 Orly Avner , Shie Mannor , Ohad Shamir

We investigate the fixed-budget best-arm identification (BAI) problem for linear bandits in a potentially non-stationary environment. Given a finite arm set $\mathcal{X}\subset\mathbb{R}^d$, a fixed budget $T$, and an unpredictable sequence…

Machine Learning · Computer Science 2024-02-16 Zhihan Xiong , Romain Camilleri , Maryam Fazel , Lalit Jain , Kevin Jamieson

This paper studies the problem of adaptively sampling from K distributions (arms) in order to identify the largest gap between any two adjacent means. We call this the MaxGap-bandit problem. This problem arises naturally in approximate…

Machine Learning · Statistics 2019-06-04 Sumeet Katariya , Ardhendu Tripathy , Robert Nowak

Motivated by recommendation problems in music streaming platforms, we propose a nonstationary stochastic bandit model in which the expected reward of an arm depends on the number of rounds that have passed since the arm was last pulled.…

Machine Learning · Statistics 2020-02-20 Leonardo Cella , Nicolò Cesa-Bianchi

This paper investigates the best arm identification (BAI) problem in stochastic multi-armed bandits in the fixed confidence setting. The general class of the exponential family of bandits is considered. The existing algorithms for the…

Machine Learning · Statistics 2023-06-26 Arpan Mukherjee , Ali Tajer