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Related papers: Optimal Best-arm Identification in Linear Bandits

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Motivated by the task of hyperparameter optimization, we introduce the non-stochastic best-arm identification problem. Within the multi-armed bandit literature, the cumulative regret objective enjoys algorithms and analyses for both the…

Machine Learning · Computer Science 2015-03-02 Kevin Jamieson , Ameet Talwalkar

We consider the question introduced by \cite{Mason2020} of identifying all the $\varepsilon$-optimal arms in a finite stochastic multi-armed bandit with Gaussian rewards. We give two lower bounds on the sample complexity of any algorithm…

Machine Learning · Statistics 2022-04-07 Aymen Al Marjani , Tomáš Kocák , Aurélien Garivier

We consider the best arm identification problem, where the goal is to identify the arm with the highest mean reward from a set of $K$ arms under a limited sampling budget. This problem models many practical scenarios such as A/B testing. We…

Machine Learning · Statistics 2026-05-05 Junpei Komiyama , Kyoungseok Jang , Junya Honda

We focus on the problem of best-arm identification in a stochastic multi-arm bandit with temporally decreasing variances for the arms' rewards. We model arm rewards as Gaussian random variables with fixed means and variances that decrease…

Machine Learning · Computer Science 2025-02-12 Tamojeet Roychowdhury , Kota Srinivas Reddy , Krishna P Jagannathan , Sharayu Moharir

The improving multi-armed bandits problem is a formal model for allocating effort under uncertainty, motivated by scenarios such as investing research effort into new technologies, performing clinical trials, and hyperparameter selection…

Machine Learning · Computer Science 2026-05-22 Avrim Blum , Marten Garicano , Kavya Ravichandran , Dravyansh Sharma

We consider the problem of best arm identification in the multi-armed bandit model, under fixed confidence. Given a confidence input $\delta$, the goal is to identify the arm with the highest mean reward with a probability of at least 1 --…

Machine Learning · Statistics 2023-12-21 El Mehdi Saad , Gilles Blanchard , Nicolas Verzelen

In a fixed-confidence pure exploration problem in stochastic multi-armed bandits, an algorithm iteratively samples arms and should stop as early as possible and return the correct answer to a query about the arms distributions. We are…

Machine Learning · Computer Science 2025-02-04 Adrienne Tuynman , Rémy Degenne

This paper studies active learning in the context of robust statistics. Specifically, we propose a variant of the Best Arm Identification problem for \emph{contaminated bandits}, where each arm pull has probability $\varepsilon$ of…

Statistics Theory · Mathematics 2021-11-16 Jason Altschuler , Victor-Emmanuel Brunel , Alan Malek

We study the problem of best arm identification in linearly parameterised multi-armed bandits. Given a set of feature vectors $\mathcal{X}\subset\mathbb{R}^d,$ a confidence parameter $\delta$ and an unknown vector $\theta^*,$ the goal is to…

Machine Learning · Computer Science 2020-06-16 Mohammadi Zaki , Avi Mohan , Aditya Gopalan

We consider the problem of identifying the best arm in stochastic Multi-Armed Bandits (MABs) using a fixed sampling budget. Characterizing the minimal instance-specific error probability for this problem constitutes one of the important…

Machine Learning · Computer Science 2024-02-21 Po-An Wang , Ruo-Chun Tzeng , Alexandre Proutiere

Learning paradigms based purely on offline data as well as those based solely on sequential online learning have been well-studied in the literature. In this paper, we consider combining offline data with online learning, an area less…

Machine Learning · Computer Science 2023-06-16 Shubhada Agrawal , Sandeep Juneja , Karthikeyan Shanmugam , Arun Sai Suggala

We study the best arm identification (BEST-1-ARM) problem, which is defined as follows. We are given $n$ stochastic bandit arms. The $i$th arm has a reward distribution $D_i$ with an unknown mean $\mu_{i}$. Upon each play of the $i$th arm,…

Machine Learning · Computer Science 2016-08-24 Lijie Chen , Jian Li

Fixed-budget best-arm identification (BAI) is a bandit problem where the agent maximizes the probability of identifying the optimal arm within a fixed budget of observations. In this work, we study this problem in the Bayesian setting. We…

Machine Learning · Computer Science 2023-06-16 Alexia Atsidakou , Sumeet Katariya , Sujay Sanghavi , Branislav Kveton

We investigate the problem of batched best arm identification in multi-armed bandits, where we aim to identify the best arm from a set of $n$ arms while minimizing both the number of samples and batches. We introduce an algorithm that…

Machine Learning · Computer Science 2025-01-30 Tianyuan Jin , Qin Zhang , Dongruo Zhou

We propose the first fully-adaptive algorithm for pure exploration in linear bandits---the task to find the arm with the largest expected reward, which depends on an unknown parameter linearly. While existing methods partially or entirely…

Machine Learning · Statistics 2017-10-17 Liyuan Xu , Junya Honda , Masashi Sugiyama

We consider the problem of the best arm identification in the presence of stochastic constraints, where there is a finite number of arms associated with multiple performance measures. The goal is to identify the arm that optimizes the…

Machine Learning · Computer Science 2025-01-08 Le Yang , Siyang Gao , Cheng Li , Yi Wang

We address the M-best-arm identification problem in multi-armed bandits. A player has a limited budget to explore K arms (M<K), and once pulled, each arm yields a reward drawn (independently) from a fixed, unknown distribution. The goal is…

Machine Learning · Statistics 2017-07-11 Shahin Shahrampour , Vahid Tarokh

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 study the Stochastic Multi-armed Bandit problem under bounded arm-memory. In this setting, the arms arrive in a stream, and the number of arms that can be stored in the memory at any time, is bounded. The decision-maker can only pull…

Machine Learning · Computer Science 2020-12-10 Arnab Maiti , Vishakha Patil , Arindam Khan

The stochastic multi-armed bandit model is a simple abstraction that has proven useful in many different contexts in statistics and machine learning. Whereas the achievable limit in terms of regret minimization is now well known, our aim is…

Machine Learning · Statistics 2016-11-15 Emilie Kaufmann , Olivier Cappé , Aurélien Garivier