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Related papers: Regret Minimization in Heavy-Tailed Bandits

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Regret minimization in stochastic non-stationary bandits gained popularity over the last decade, as it can model a broad class of real-world problems, from advertising to recommendation systems. Existing literature relies on various…

Machine Learning · Computer Science 2025-05-27 Gianmarco Genalti , Sujay Bhatt , Nicola Gatti , Alberto Maria Metelli

Motivated by practical applications, chiefly clinical trials, we study the regret achievable for stochastic bandits under the constraint that the employed policy must split trials into a small number of batches. We propose a simple policy,…

Statistics Theory · Mathematics 2016-03-30 Vianney Perchet , Philippe Rigollet , Sylvain Chassang , Erik Snowberg

We study the $K$-armed dueling bandit problem, a variation of the standard stochastic bandit problem where the feedback is limited to relative comparisons of a pair of arms. We introduce a tight asymptotic regret lower bound that is based…

Machine Learning · Statistics 2015-06-30 Junpei Komiyama , Junya Honda , Hisashi Kashima , Hiroshi Nakagawa

Despite a large amount of effort in dealing with heavy-tailed error in machine learning, little is known when moments of the error can become non-existential: the random noise $\eta$ satisfies Pr$\left[|\eta| > |y|\right] \le…

Machine Learning · Computer Science 2021-10-27 Han Zhong , Jiayi Huang , Lin F. Yang , Liwei Wang

In this paper we propose a novel experimental design-based algorithm to minimize regret in online stochastic linear and combinatorial bandits. While existing literature tends to focus on optimism-based algorithms--which have been shown to…

Machine Learning · Computer Science 2021-03-02 Andrew Wagenmaker , Julian Katz-Samuels , Kevin Jamieson

We study the optimal batch-regret tradeoff for batch linear contextual bandits. For any batch number $M$, number of actions $K$, time horizon $T$, and dimension $d$, we provide an algorithm and prove its regret guarantee, which, due to…

Machine Learning · Computer Science 2022-10-18 Zihan Zhang , Xiangyang Ji , Yuan Zhou

We consider the Multi-Armed Bandit (MAB) problem, where an agent sequentially chooses actions and observes rewards for the actions it took. While the majority of algorithms try to minimize the regret, i.e., the cumulative difference between…

Machine Learning · Computer Science 2021-09-14 Nadav Merlis , Shie Mannor

While numerous works have focused on devising efficient algorithms for reinforcement learning (RL) with uniformly bounded rewards, it remains an open question whether sample or time-efficient algorithms for RL with large state-action space…

Machine Learning · Computer Science 2024-03-08 Jiayi Huang , Han Zhong , Liwei Wang , Lin F. Yang

Motivated by the concept of satisficing in decision-making, we consider the problem of satisficing regret minimization in bandit optimization. In this setting, the learner aims at selecting satisficing arms (arms with mean reward exceeding…

Machine Learning · Statistics 2025-07-01 Qing Feng , Tianyi Ma , Ruihao Zhu

Partial monitoring is a general model for sequential learning with limited feedback formalized as a game between two players. In this game, the learner chooses an action and at the same time the opponent chooses an outcome, then the learner…

Machine Learning · Statistics 2015-10-01 Junpei Komiyama , Junya Honda , Hiroshi Nakagawa

We study regret minimization in a stochastic multi-armed bandit setting and establish a fundamental trade-off between the regret suffered under an algorithm, and its statistical robustness. Considering broad classes of underlying arms'…

Machine Learning · Computer Science 2020-06-23 Kumar Ashutosh , Jayakrishnan Nair , Anmol Kagrecha , Krishna Jagannathan

In linear stochastic bandits, it is commonly assumed that payoffs are with sub-Gaussian noises. In this paper, under a weaker assumption on noises, we study the problem of \underline{lin}ear stochastic {\underline b}andits with h{\underline…

Machine Learning · Computer Science 2018-11-13 Han Shao , Xiaotian Yu , Irwin King , Michael R. Lyu

In multi-armed bandit problems, the typical goal is to identify the arm with the highest reward. This paper explores a threshold-based bandit problem, aiming to select an arm based on its relation to a prescribed threshold \(\tau \). We…

Machine Learning · Computer Science 2025-09-03 Chanakya Varude , Jay Chaudhary , Siddharth Kaushik , Prasanna Chaporkar

We consider the classical stochastic multi-armed bandit but where, from time to time and roughly with frequency $\epsilon$, an extra observation is gathered by the agent for free. We prove that, no matter how small $\epsilon$ is the agent…

Machine Learning · Computer Science 2018-07-11 Rémy Degenne , Evrard Garcelon , Vianney Perchet

We propose a simple model selection approach for algorithms in stochastic bandit and reinforcement learning problems. As opposed to prior work that (implicitly) assumes knowledge of the optimal regret, we only require that each base…

Machine Learning · Computer Science 2020-12-25 Aldo Pacchiano , Christoph Dann , Claudio Gentile , Peter Bartlett

The Greedy algorithm is the simplest heuristic in sequential decision problem that carelessly takes the locally optimal choice at each round, disregarding any advantages of exploring and/or information gathering. Theoretically, it is known…

Machine Learning · Computer Science 2021-01-05 Matthieu Jedor , Jonathan Louëdec , Vianney Perchet

This paper investigates the problem of generalized linear bandits with heavy-tailed rewards, whose $(1+\epsilon)$-th moment is bounded for some $\epsilon\in (0,1]$. Although there exist methods for generalized linear bandits, most of them…

Machine Learning · Computer Science 2023-10-31 Bo Xue , Yimu Wang , Yuanyu Wan , Jinfeng Yi , Lijun Zhang

In many applications, e.g. in healthcare and e-commerce, the goal of a contextual bandit may be to learn an optimal treatment assignment policy at the end of the experiment. That is, to minimize simple regret. However, this objective…

Machine Learning · Computer Science 2023-11-06 Sanath Kumar Krishnamurthy , Ruohan Zhan , Susan Athey , Emma Brunskill

In this paper, we consider the problem of black-box optimization with noisy feedback revealed in batches, where the unknown function to optimize has a bounded norm in some Reproducing Kernel Hilbert Space (RKHS). We refer to this as the…

Machine Learning · Statistics 2026-03-16 Chenkai Ma , Keqin Chen , Jonathan Scarlett

We consider combinatorial semi-bandits over a set of arms ${\cal X} \subset \{0,1\}^d$ where rewards are uncorrelated across items. For this problem, the algorithm ESCB yields the smallest known regret bound $R(T) = {\cal O}\Big( {d (\ln…

Machine Learning · Statistics 2021-01-14 Thibaut Cuvelier , Richard Combes , Eric Gourdin