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Related papers: Regularized Contextual Bandits

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In this work, we develop linear bandit algorithms that automatically adapt to different environments. By plugging a novel loss estimator into the optimization problem that characterizes the instance-optimal strategy, our first algorithm not…

Machine Learning · Computer Science 2021-06-15 Chung-Wei Lee , Haipeng Luo , Chen-Yu Wei , Mengxiao Zhang , Xiaojin Zhang

We study a variant of causal contextual bandits where the context is chosen based on an initial intervention chosen by the learner. At the beginning of each round, the learner selects an initial action, depending on which a stochastic…

Machine Learning · Computer Science 2024-06-04 Rahul Madhavan , Aurghya Maiti , Gaurav Sinha , Siddharth Barman

We establish an asymptotic framework for the statistical analysis of the stochastic contextual multi-armed bandit problem (CMAB), which is widely employed in adaptively randomized experiments across various fields. While algorithms for…

Econometrics · Economics 2025-05-21 Ramon van den Akker , Bas J. M. Werker , Bo Zhou

We study the problem of contextual combinatorial semi-bandits, where input contexts are mapped into subsets of size $m$ of a collection of $K$ possible actions. In each round, the learner observes the realized reward of the predicted…

Machine Learning · Computer Science 2026-02-24 Liad Erez , Tomer Koren

We introduce the functional bandit problem, where the objective is to find an arm that optimises a known functional of the unknown arm-reward distributions. These problems arise in many settings such as maximum entropy methods in natural…

Machine Learning · Statistics 2014-05-13 Long Tran-Thanh , Jia Yuan Yu

Contextual bandit algorithms are essential for solving real-world decision making problems. In practice, collecting a contextual bandit's feedback from different domains may involve different costs. For example, measuring drug reaction from…

Machine Learning · Computer Science 2025-04-08 Ziyan Wang , Xiaoming Huo , Hao Wang

We consider a multi-armed bandit problem motivated by situations where only the extreme values, as opposed to expected values in the classical bandit setting, are of interest. We propose distribution free algorithms using robust statistics…

Machine Learning · Statistics 2021-09-10 Sujay Bhatt , Ping Li , Gennady Samorodnitsky

We study how representation learning can improve the learning efficiency of contextual bandit problems. We study the setting where we play T contextual linear bandits with dimension d simultaneously, and these T bandit tasks collectively…

Machine Learning · Computer Science 2025-01-08 Jiabin Lin , Shana Moothedath , Namrata Vaswani

The contextual bandit problem, which is a type of reinforcement learning tasks, provides an effective framework for solving challenges in recommendation systems, such as satisfying real-time requirements, enabling personalization,…

Machine Learning · Computer Science 2025-01-16 Shogo Ito , Tatsuji Takahashi , Yu Kono

We consider the problem of contextual bandits where actions are subsets of a ground set and mean rewards are modeled by an unknown monotone submodular function that belongs to a class $\mathcal{F}$. We allow time-varying matroid constraints…

Machine Learning · Computer Science 2021-12-07 Dean P. Foster , Alexander Rakhlin

We consider a contextual bandit problem with $S$ contexts and $K$ actions. In each round $t=1,2,\dots$, the learner observes a random context and chooses an action based on its past experience. The learner then observes a random reward…

Machine Learning · Computer Science 2023-11-29 Chung-Wei Lee , Qinghua Liu , Yasin Abbasi-Yadkori , Chi Jin , Tor Lattimore , Csaba Szepesvári

In a typical stochastic multi-armed bandit problem, the objective is often to maximize the expected sum of rewards over some time horizon $T$. While the choice of a strategy that accomplishes that is optimal with no additional information,…

Machine Learning · Computer Science 2023-11-01 Reda Alami , Mohammed Mahfoud , Mastane Achab

In today's technology environment, information is abundant, dynamic, and heterogeneous in nature. Automated filtering and prioritization of information is based on the distinction between whether the information adds substantial value…

Machine Learning · Computer Science 2022-02-01 Jade Freeman , Michael Rawson

As the adoption of federated learning increases for learning from sensitive data local to user devices, it is natural to ask if the learning can be done using implicit signals generated as users interact with the applications of interest,…

Machine Learning · Computer Science 2023-03-21 Alekh Agarwal , H. Brendan McMahan , Zheng Xu

We consider the stochastic contextual bandit problem under the high dimensional linear model. We focus on the case where the action space is finite and random, with each action associated with a randomly generated contextual covariate. This…

Machine Learning · Statistics 2020-09-07 Yining Wang , Yi Chen , Ethan X. Fang , Zhaoran Wang , Runze Li

In this paper, we introduce a multi-armed bandit problem termed max-min grouped bandits, in which the arms are arranged in possibly-overlapping groups, and the goal is to find the group whose worst arm has the highest mean reward. This…

Machine Learning · Statistics 2022-03-16 Zhenlin Wang , Jonathan Scarlett

Contextual bandit and reinforcement learning algorithms have been successfully used in various interactive learning systems such as online advertising, recommender systems, and dynamic pricing. However, they have yet to be widely adopted in…

Machine Learning · Computer Science 2022-09-23 Sorawit Saengkyongam , Nikolaj Thams , Jonas Peters , Niklas Pfister

Canonical algorithms for multi-armed bandits typically assume a stationary reward environment where the size of the action space (number of arms) is small. More recently developed methods typically relax only one of these assumptions:…

Machine Learning · Computer Science 2025-06-02 Derek Everett , Fred Lu , Edward Raff , Fernando Camacho , James Holt

We give an oracle-based algorithm for the adversarial contextual bandit problem, where either contexts are drawn i.i.d. or the sequence of contexts is known a priori, but where the losses are picked adversarially. Our algorithm is…

Machine Learning · Computer Science 2016-06-02 Vasilis Syrgkanis , Haipeng Luo , Akshay Krishnamurthy , Robert E. Schapire

Multi-armed bandit problems are receiving a great deal of attention because they adequately formalize the exploration-exploitation trade-offs arising in several industrially relevant applications, such as online advertisement and, more…

Machine Learning · Computer Science 2013-11-05 Nicolò Cesa-Bianchi , Claudio Gentile , Giovanni Zappella