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Related papers: Towards Optimal and Efficient Best Arm Identificat…

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The regret lower bound of Lai and Robbins (1985), the gold standard for checking optimality of bandit algorithms, considers arm size fixed as sample size goes to infinity. We show that when arm size increases polynomially with sample size,…

Statistics Theory · Mathematics 2019-09-06 Hock Peng Chan , Shouri Hu

We study the problem of collaborative best-arm identification in stochastic linear bandits under a fixed-budget scenario. In our learning model, we first consider multiple agents connected through a star network, interacting with a linear…

Machine Learning · Computer Science 2025-05-27 Sanjana Agrawal , Saúl A. Blanco

A Top Two sampling rule for bandit identification is a method which selects the next arm to sample from among two candidate arms, a leader and a challenger. Due to their simplicity and good empirical performance, they have received…

Machine Learning · Statistics 2023-11-08 Marc Jourdan , Rémy Degenne

This work investigates the problem of best arm identification for multi-agent multi-armed bandits. We consider $N$ agents grouped into $M$ clusters, where each cluster solves a stochastic bandit problem. The mapping between agents and…

Machine Learning · Computer Science 2025-05-16 Yash , Nikhil Karamchandani , Avishek Ghosh

We study best arm identification in a variant of the multi-armed bandit problem where the learner has limited precision in arm selection. The learner can only sample arms via certain exploration bundles, which we refer to as boxes. In…

Machine Learning · Computer Science 2023-05-11 Kota Srinivas Reddy , P. N. Karthik , Nikhil Karamchandani , Jayakrishnan Nair

We study the best-arm identification problem in multi-armed bandits with stochastic, potentially private rewards, when the goal is to identify the arm with the highest quantile at a fixed, prescribed level. First, we propose a (non-private)…

Machine Learning · Statistics 2022-12-06 Kontantinos E. Nikolakakis , Dionysios S. Kalogerias , Or Sheffet , Anand D. Sarwate

This paper formulates a new Best-Arm Identification problem in the non-stationary stochastic bandits setting, where the means of all arms are shifted in the same way due to a global influence of the environment. The aim is to identify the…

Machine Learning · Computer Science 2024-08-23 Phurinut Srisawad , Juergen Branke , Long Tran-Thanh

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

We consider the best-arm identification problem in multi-armed bandits, which focuses purely on exploration. A player is given a fixed budget to explore a finite set of arms, and the rewards of each arm are drawn independently from a fixed,…

Machine Learning · Statistics 2017-08-02 Shahin Shahrampour , Mohammad Noshad , Vahid Tarokh

We study fixed-confidence best arm identification in generalized linear bandits under a hybrid feedback model: at each round, the learner may query either (i) absolute reward feedback from a single arm or (ii) relative (dueling) feedback…

Artificial Intelligence · Computer Science 2026-05-08 Qirun Zeng , Xuchuang Wang , Jiayi Shen , Xutong Liu , Fang Kong , Jinhang Zuo

We lay the foundations of a non-parametric theory of best-arm identification in multi-armed bandits with a fixed budget T. We consider general, possibly non-parametric, models D for distributions over the arms; an overarching example is the…

Machine Learning · Computer Science 2023-02-07 Antoine Barrier , Aurélien Garivier , Gilles Stoltz

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

Motivated by real-world applications that necessitate responsible experimentation, we introduce the problem of best arm identification (BAI) with minimal regret. This innovative variant of the multi-armed bandit problem elegantly…

Machine Learning · Computer Science 2024-09-30 Junwen Yang , Vincent Y. F. Tan , Tianyuan Jin

We study a novel pure exploration problem: the $\epsilon$-Thresholding Bandit Problem (TBP) with fixed confidence in stochastic linear bandits. We prove a lower bound for the sample complexity and extend an algorithm designed for Best Arm…

Machine Learning · Statistics 2024-02-16 Eduardo Ochoa Rivera , Ambuj Tewari

Active learning methods have shown great promise in reducing the number of samples necessary for learning. As automated learning systems are adopted into real-time, real-world decision-making pipelines, it is increasingly important that…

Machine Learning · Computer Science 2022-06-23 Romain Camilleri , Andrew Wagenmaker , Jamie Morgenstern , Lalit Jain , Kevin Jamieson

Upper Confidence Bound (UCB) is arguably the most commonly used method for linear multi-arm bandit problems. While conceptually and computationally simple, this method highly relies on the confidence bounds, failing to strike the optimal…

Machine Learning · Computer Science 2020-06-05 Kaige Yang , Laura Toni

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 a good arm identification problem in a stochastic bandit setting with multi-objectives, where each arm $i \in [K]$ is associated with a distribution $D_i$ defined over $R^M$. For each round $t$, the player pulls an arm $i_t$ and…

Machine Learning · Computer Science 2025-06-30 Xuanke Jiang , Sherief Hashima , Kohei Hatano , Eiji Takimoto

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

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