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Related papers: Sparse Nonparametric Contextual Bandits

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In this paper, we study both multi-armed and contextual bandit problems in censored environments. Our goal is to estimate the performance loss due to censorship in the context of classical algorithms designed for uncensored environments.…

Machine Learning · Computer Science 2023-02-15 Gauthier Guinet , Saurabh Amin , Patrick Jaillet

Using bandit algorithms to conduct adaptive randomised experiments can minimise regret, but it poses major challenges for statistical inference (e.g., biased estimators, inflated type-I error and reduced power). Recent attempts to address…

Machine Learning · Statistics 2021-11-02 Nina Deliu , Joseph J. Williams , Sofia S. Villar

In multi-objective decision-making with hierarchical preferences, lexicographic bandits provide a natural framework for optimizing multiple objectives in a prioritized order. In this setting, a learner repeatedly selects arms and observes…

Machine Learning · Computer Science 2025-11-11 Bo Xue , Yuanyu Wan , Zhichao Lu , Qingfu Zhang

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

In this paper we propose the multi-objective contextual bandit problem with similarity information. This problem extends the classical contextual bandit problem with similarity information by introducing multiple and possibly conflicting…

Machine Learning · Statistics 2018-03-13 Eralp Turğay , Doruk Öner , Cem Tekin

In stochastic contextual bandits, an agent sequentially makes actions from a time-dependent action set based on past experience to minimize the cumulative regret. Like many other machine learning algorithms, the performance of bandits…

Machine Learning · Computer Science 2024-04-09 Yue Kang , Cho-Jui Hsieh , Thomas C. M. Lee

We study the $K$-armed contextual dueling bandit problem, a sequential decision making setting in which the learner uses contextual information to make two decisions, but only observes \emph{preference-based feedback} suggesting that one…

Machine Learning · Computer Science 2021-11-25 Aadirupa Saha , Akshay Krishnamurthy

We study the problem of regret minimization in a multi-armed bandit setup where the agent is allowed to play multiple arms at each round by spreading the resources usually allocated to only one arm. At each iteration the agent selects a…

Machine Learning · Computer Science 2021-06-01 Matias I. Müller , Cristian R. Rojas

We study contextual bandit learning with an abstract policy class and continuous action space. We obtain two qualitatively different regret bounds: one competes with a smoothed version of the policy class under no continuity assumptions,…

Machine Learning · Statistics 2020-06-23 Akshay Krishnamurthy , John Langford , Aleksandrs Slivkins , Chicheng Zhang

We study the problem of dynamic batch learning in high-dimensional sparse linear contextual bandits, where a decision maker, under a given maximum-number-of-batch constraint and only able to observe rewards at the end of each batch, can…

Machine Learning · Statistics 2022-07-19 Zhimei Ren , Zhengyuan Zhou

We present the first high-probability optimal regret bound for a policy optimization technique applied to the problem of stochastic contextual multi-armed bandit (CMAB) with general offline function approximation. Our algorithm is both…

Machine Learning · Computer Science 2026-02-17 Orin Levy , Yishay Mansour

Stochastic linear bandits with high-dimensional sparse features are a practical model for a variety of domains, including personalized medicine and online advertising. We derive a novel $\Omega(n^{2/3})$ dimension-free minimax regret lower…

Machine Learning · Statistics 2021-09-07 Botao Hao , Tor Lattimore , Mengdi Wang

High-dimensional linear contextual bandit problems remain a significant challenge due to the curse of dimensionality. Existing methods typically consider either the model parameters to be sparse or the eigenvalues of context covariance…

Statistics Theory · Mathematics 2025-10-10 Rui Zhao , Zihan Chen , Zemin Zheng

We consider a variant of the contextual bandit problem. In standard contextual bandits, when a user arrives we get the user's complete feature vector and then assign a treatment (arm) to that user. In a number of applications (like…

Machine Learning · Computer Science 2020-02-25 Sanath Kumar Krishnamurthy , Susan Athey

Taking advantage of contextual information can potentially boost the performance of recommender systems. In the era of big data, such side information often has several dimensions. Thus, developing decision-making algorithms to cope with…

Machine Learning · Computer Science 2023-07-26 Saeed Ghoorchian , Evgenii Kortukov , Setareh Maghsudi

Contextual bandit algorithms have become widely used for recommendation in online systems (e.g. marketplaces, music streaming, news), where they now wield substantial influence on which items get exposed to the users. This raises questions…

Machine Learning · Computer Science 2021-09-14 Lequn Wang , Yiwei Bai , Wen Sun , Thorsten Joachims

In this paper, we propose a constant word (RAM model) algorithm for regret minimisation for both finite and infinite Stochastic Multi-Armed Bandit (MAB) instances. Most of the existing regret minimisation algorithms need to remember the…

Machine Learning · Computer Science 2019-01-25 Arghya Roy Chaudhuri , Shivaram Kalyanakrishnan

The cross-learning contextual bandit problem with graphical feedback has recently attracted significant attention. In this setting, there is a contextual bandit with a feedback graph over the arms, and pulling an arm reveals the loss for…

Machine Learning · Computer Science 2025-02-10 Ruiyuan Huang , Zengfeng Huang

Motivated by applications in online bidding and sleeping bandits, we examine the problem of contextual bandits with cross learning, where the learner observes the loss associated with the action across all possible contexts, not just the…

Machine Learning · Computer Science 2025-01-27 Ruiyuan Huang , Zengfeng Huang

Contextual bandits are widely used in industrial personalization systems. These online learning frameworks learn a treatment assignment policy in the presence of treatment effects that vary with the observed contextual features of the…

Machine Learning · Computer Science 2022-05-11 Claudia Roberts , Maria Dimakopoulou , Qifeng Qiao , Ashok Chandrashekhar , Tony Jebara