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Related papers: Best arm identification in rare events

200 papers

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

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

In this paper, we introduce the constrained best mixed arm identification (CBMAI) problem with a fixed budget. This is a pure exploration problem in a stochastic finite armed bandit model. Each arm is associated with a reward and multiple…

Machine Learning · Computer Science 2024-05-27 Dengwang Tang , Rahul Jain , Ashutosh Nayyar , Pierluigi Nuzzo

In fixed-confidence best arm identification (BAI), the objective is to quickly identify the optimal option while controlling the probability of error below a desired threshold. Despite the plethora of BAI algorithms, existing methods…

Machine Learning · Computer Science 2026-01-05 Brian M. Cho , Nathan Kallus

We study the best-arm identification problem with fixed confidence when contextual (covariate) information is available in stochastic bandits. Although we can use contextual information in each round, we are interested in the marginalized…

Machine Learning · Computer Science 2024-02-27 Masahiro Kato , Kaito Ariu

We consider the problem of \textit{best arm identification} with a \textit{fixed budget $T$}, in the $K$-armed stochastic bandit setting, with arms distribution defined on $[0,1]$. We prove that any bandit strategy, for at least one bandit…

Machine Learning · Statistics 2016-05-31 Alexandra Carpentier , Andrea Locatelli

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 examine a multi-armed bandit problem with contextual information, where the objective is to ensure that each arm receives a minimum aggregated reward across contexts while simultaneously maximizing the total cumulative reward. This…

Machine Learning · Computer Science 2025-10-15 Ahmed Ben Yahmed , Hafedh El Ferchichi , Marc Abeille , Vianney Perchet

We study the batched best arm identification (BBAI) problem, where the learner's goal is to identify the best arm while switching the policy as less as possible. In particular, we aim to find the best arm with probability $1-\delta$ for…

Machine Learning · Computer Science 2025-03-05 Tianyuan Jin , Yu Yang , Jing Tang , Xiaokui Xiao , Pan Xu

Recent work has considered natural variations of the multi-armed bandit problem, where the reward distribution of each arm is a special function of the time passed since its last pulling. In this direction, a simple (yet widely applicable)…

Machine Learning · Computer Science 2021-05-25 Alexia Atsidakou , Orestis Papadigenopoulos , Soumya Basu , Constantine Caramanis , Sanjay Shakkottai

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

In the Best-$k$-Arm problem, we are given $n$ stochastic bandit arms, each associated with an unknown reward distribution. We are required to identify the $k$ arms with the largest means by taking as few samples as possible. In this paper,…

Machine Learning · Computer Science 2017-02-15 Lijie Chen , Jian Li , Mingda Qiao

Classical multi-armed bandit problems use the expected value of an arm as a metric to evaluate its goodness. However, the expected value is a risk-neutral metric. In many applications like finance, one is interested in balancing the…

Machine Learning · Computer Science 2019-06-04 Anmol Kagrecha , Jayakrishnan Nair , Krishna Jagannathan

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

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

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

This paper studies the fixed-confidence best arm identification (BAI) problem in the bandit framework in the canonical single-parameter exponential models. For this problem, many policies have been proposed, but most of them require solving…

Machine Learning · Statistics 2025-08-12 Jongyeong Lee , Junya Honda , Masashi Sugiyama

This paper targets a variant of the stochastic multi-armed bandit problem called good arm identification (GAI). GAI is a pure-exploration bandit problem with the goal to output as many good arms using as few samples as possible, where a…

Machine Learning · Computer Science 2024-02-19 Yun-Da Tsai , Tzu-Hsien Tsai , Shou-De Lin

We propose a {\em novel} piecewise stationary linear bandit (PSLB) model, where the environment randomly samples a context from an unknown probability distribution at each changepoint, and the quality of an arm is measured by its return…

Machine Learning · Computer Science 2024-10-11 Yunlong Hou , Vincent Y. F. Tan , Zixin Zhong

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