English
Related papers

Related papers: The Fragility of Optimized Bandit Algorithms

200 papers

We study the optimal trade-off between expectation and tail risk for regret distribution in the stochastic multi-armed bandit model. We fully characterize the interplay among three desired properties for policy design: worst-case…

Machine Learning · Statistics 2025-10-27 David Simchi-Levi , Zeyu Zheng , Feng Zhu

In this work, we address the open problem of finding low-complexity near-optimal multi-armed bandit algorithms for sequential decision making problems. Existing bandit algorithms are either sub-optimal and computationally simple (e.g.,…

Machine Learning · Computer Science 2018-04-18 Fang Liu , Sinong Wang , Swapna Buccapatnam , Ness Shroff

Multiplayer bandits have recently been extensively studied because of their application to cognitive radio networks. While the literature mostly considers synchronous players, radio networks (e.g. for IoT) tend to have asynchronous devices.…

Machine Learning · Computer Science 2023-06-01 Hugo Richard , Etienne Boursier , Vianney Perchet

Most bandit algorithm designs are purely theoretical. Therefore, they have strong regret guarantees, but also are often too conservative in practice. In this work, we pioneer the idea of algorithm design by minimizing the empirical Bayes…

Machine Learning · Computer Science 2020-06-12 Chih-Wei Hsu , Branislav Kveton , Ofer Meshi , Martin Mladenov , Csaba Szepesvari

This paper studies regret minimization in a multi-armed bandit. It is well known that side information, such as the prior distribution of arm means in Thompson sampling, can improve the statistical efficiency of the bandit algorithm. While…

Machine Learning · Computer Science 2022-03-08 Rong Zhu , Branislav Kveton

The problem of bandit with graph feedback generalizes both the multi-armed bandit (MAB) problem and the learning with expert advice problem by encoding in a directed graph how the loss vector can be observed in each round of the game. The…

Machine Learning · Computer Science 2023-08-07 Yuchen He , Chihao Zhang

In this paper, we introduce Ballooning Multi-Armed Bandits (BL-MAB), a novel extension of the classical stochastic MAB model. In the BL-MAB model, the set of available arms grows (or balloons) over time. In contrast to the classical MAB…

Machine Learning · Computer Science 2021-02-23 Ganesh Ghalme , Swapnil Dhamal , Shweta Jain , Sujit Gujar , Y. Narahari

We consider a multi-armed bandit problem in which a set of arms is registered by each agent, and the agent receives reward when its arm is selected. An agent might strategically submit more arms with replications, which can bring more…

Machine Learning · Computer Science 2021-10-26 Suho Shin , Seungjoon Lee , Jungseul Ok

We define a general framework for a large class of combinatorial multi-armed bandit (CMAB) problems, where subsets of base arms with unknown distributions form super arms. In each round, a super arm is played and the base arms contained in…

Machine Learning · Computer Science 2016-03-30 Wei Chen , Yajun Wang , Yang Yuan , Qinshi Wang

We propose $\tt RandUCB$, a bandit strategy that builds on theoretically derived confidence intervals similar to upper confidence bound (UCB) algorithms, but akin to Thompson sampling (TS), it uses randomization to trade off exploration and…

Machine Learning · Computer Science 2020-03-24 Sharan Vaswani , Abbas Mehrabian , Audrey Durand , Branislav Kveton

We consider a stochastic multi-armed bandit (MAB) problem motivated by ``large'' action spaces, and endowed with a population of arms containing exactly $K$ arm-types, each characterized by a distinct mean reward. The decision maker is…

Machine Learning · Computer Science 2023-01-19 Anand Kalvit , Assaf Zeevi

We study online fair division when there are a finite number of item types and the player values for the items are drawn randomly from distributions with unknown means. In this setting, a sequence of indivisible items arrives according to a…

Computer Science and Game Theory · Computer Science 2025-01-14 Benjamin Schiffer , Shirley Zhang

Heavy-tailed distributions naturally arise in several settings, from finance to telecommunications. While regret minimization under subgaussian or bounded rewards has been widely studied, learning with heavy-tailed distributions only gained…

Machine Learning · Computer Science 2024-02-13 Gianmarco Genalti , Lupo Marsigli , Nicola Gatti , Alberto Maria Metelli

We study the nonstationary stochastic Multi-Armed Bandit (MAB) problem in which the distribution of rewards associated with each arm are assumed to be time-varying and the total variation in the expected rewards is subject to a variation…

Machine Learning · Computer Science 2021-01-25 Lai Wei , Vaibhav Srivastava

Strategic behavior against sequential learning methods, such as "click framing" in real recommendation systems, have been widely observed. Motivated by such behavior we study the problem of combinatorial multi-armed bandits (CMAB) under…

Machine Learning · Computer Science 2021-11-22 Jing Dong , Ke Li , Shuai Li , Baoxiang Wang

This paper is in the field of stochastic Multi-Armed Bandits (MABs), i.e. those sequential selection techniques able to learn online using only the feedback given by the chosen option (a.k.a. $arm$). We study a particular case of the rested…

Machine Learning · Statistics 2024-11-28 Marco Fiandri , Alberto Maria Metelli , Francesco Trov`o

Optimal regret bounds for Multi-Armed Bandit problems are now well documented. They can be classified into two categories based on the growth rate with respect to the time horizon $T$: (i) small, distribution-dependent, bounds of order of…

Data Structures and Algorithms · Computer Science 2017-04-12 Arthur Flajolet , Patrick Jaillet

Fast changing states or volatile environments pose a significant challenge to online optimization, which needs to perform rapid adaptation under limited observation. In this paper, we give query and regret optimal bandit algorithms under…

Machine Learning · Computer Science 2024-01-18 Zhou Lu , Qiuyi Zhang , Xinyi Chen , Fred Zhang , David Woodruff , Elad Hazan

We study an important variant of the stochastic multi-armed bandit (MAB) problem, which takes penalization into consideration. Instead of directly maximizing cumulative expected reward, we need to balance between the total reward and…

Machine Learning · Statistics 2022-11-16 Guanhua Fang , Ping Li , Gennady Samorodnitsky

We investigate a Bayesian $k$-armed bandit problem in the \emph{many-armed} regime, where $k \geq \sqrt{T}$ and $T$ represents the time horizon. Initially, and aligned with recent literature on many-armed bandit problems, we observe that…

Machine Learning · Computer Science 2024-03-21 Mohsen Bayati , Nima Hamidi , Ramesh Johari , Khashayar Khosravi