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Related papers: Tractable contextual bandits beyond realizability

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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

This paper presents a new contextual bandit algorithm, NeuralBandit, which does not need hypothesis on stationarity of contexts and rewards. Several neural networks are trained to modelize the value of rewards knowing the context. Two…

Neural and Evolutionary Computing · Computer Science 2014-09-30 Robin Allesiardo , Raphael Feraud , Djallel Bouneffouf

Bandit optimization is a difficult problem, especially if the reward model is high-dimensional. When rewards are modeled by neural networks, sublinear regret has only been shown under strong assumptions, usually when the network is…

Machine Learning · Computer Science 2025-01-14 Mikhail Terekhov

Safety is a desirable property that can immensely increase the applicability of learning algorithms in real-world decision-making problems. It is much easier for a company to deploy an algorithm that is safe, i.e., guaranteed to perform at…

Machine Learning · Statistics 2017-03-07 Abbas Kazerouni , Mohammad Ghavamzadeh , Yasin Abbasi-Yadkori , Benjamin Van Roy

We consider a contextual combinatorial bandit problem where in each round a learning agent selects a subset of arms and receives feedback on the selected arms according to their scores. The score of an arm is an unknown function of the…

Machine Learning · Statistics 2023-06-02 Taehyun Hwang , Kyuwook Chai , Min-hwan Oh

We introduce the study of fairness in multi-armed bandit problems. Our fairness definition can be interpreted as demanding that given a pool of applicants (say, for college admission or mortgages), a worse applicant is never favored over a…

Machine Learning · Computer Science 2016-11-08 Matthew Joseph , Michael Kearns , Jamie Morgenstern , Aaron Roth

We study linear contextual bandits in the misspecified setting, where the expected reward function can be approximated by a linear function class up to a bounded misspecification level $\zeta>0$. We propose an algorithm based on a novel…

Machine Learning · Computer Science 2023-03-17 Weitong Zhang , Jiafan He , Zhiyuan Fan , Quanquan Gu

We study nonparametric contextual bandits under batch constraints, where the expected reward for each action is modeled as a smooth function of covariates, and the policy updates are made at the end of each batch of observations. We…

Statistics Theory · Mathematics 2025-10-06 Rong Jiang , Cong Ma

Much of the recent literature on bandit learning focuses on algorithms that aim to converge on an optimal action. One shortcoming is that this orientation does not account for time sensitivity, which can play a crucial role when learning an…

Machine Learning · Computer Science 2020-01-09 Daniel Russo , Benjamin Van Roy

In bandit settings, optimizing long-term regret metrics requires exploration, which corresponds to sometimes taking myopically sub-optimal actions. When a long-lived principal merely recommends actions to be executed by a sequence of…

Computer Science and Game Theory · Computer Science 2026-02-25 Ramya Ramalingam , Osbert Bastani , Aaron Roth

We study how to learn optimal interventions sequentially given causal information represented as a causal graph along with associated conditional distributions. Causal modeling is useful in real world problems like online advertisement…

Machine Learning · Statistics 2020-06-12 Yangyi Lu , Amirhossein Meisami , Ambuj Tewari , Zhenyu Yan

We study contextual bandits with ancillary constraints on resources, which are common in real-world applications such as choosing ads or dynamic pricing of items. We design the first algorithm for solving these problems that handles…

Machine Learning · Computer Science 2015-08-03 Ashwinkumar Badanidiyuru , John Langford , Aleksandrs Slivkins

We study contextual bandit (CB) problems, where the user can sometimes respond with the best action in a given context. Such an interaction arises, for example, in text prediction or autocompletion settings, where a poor suggestion is…

Machine Learning · Computer Science 2023-02-09 Alekh Agarwal , Claudio Gentile , Teodor V. Marinov

The Causal Bandit is a variant of the classic Bandit problem where an agent must identify the best action in a sequential decision-making process, where the reward distribution of the actions displays a non-trivial dependence structure that…

Artificial Intelligence · Computer Science 2022-09-30 Arnoud A. W. M. de Kroon , Danielle Belgrave , Joris M. Mooij

We study the contextual linear bandit problem, a version of the standard stochastic multi-armed bandit (MAB) problem where a learner sequentially selects actions to maximize a reward which depends also on a user provided per-round context.…

Machine Learning · Computer Science 2018-10-02 Roshan Shariff , Or Sheffet

Causal bandit is a nascent learning model where an agent sequentially experiments in a causal network of variables, in order to identify the reward-maximizing intervention. Despite the model's wide applicability, existing analytical results…

Machine Learning · Statistics 2021-03-09 Ruiyang Song , Stefano Rini , Kuang Xu

There are two variants of the classical multi-armed bandit (MAB) problem that have received considerable attention from machine learning researchers in recent years: contextual bandits and simple regret minimization. Contextual bandits are…

Machine Learning · Statistics 2020-02-27 Aniket Anand Deshmukh , Srinagesh Sharma , James W. Cutler , Mark Moldwin , Clayton Scott

We study the problem of federated stochastic multi-arm contextual bandits with unknown contexts, in which M agents are faced with different bandits and collaborate to learn. The communication model consists of a central server and the…

Machine Learning · Computer Science 2024-01-31 Jiabin Lin , Shana Moothedath

Nonparametric contextual bandit is an important model of sequential decision making problems. Under $\alpha$-Tsybakov margin condition, existing research has established a regret bound of $\tilde{O}\left(T^{1-\frac{\alpha+1}{d+2}}\right)$…

Machine Learning · Computer Science 2025-05-09 Puning Zhao , Rongfei Fan , Shaowei Wang , Li Shen , Qixin Zhang , Zong Ke , Tianhang Zheng

Thompson Sampling (TS) is one of the most effective algorithms for solving contextual multi-armed bandit problems. In this paper, we propose a new algorithm, called Neural Thompson Sampling, which adapts deep neural networks for both…

Machine Learning · Computer Science 2022-01-03 Weitong Zhang , Dongruo Zhou , Lihong Li , Quanquan Gu