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Related papers: Near-Optimal Regret in Adversarial Kernel Bandits

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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

We study stochastic linear optimization problem with bandit feedback. The set of arms take values in an $N$-dimensional space and belong to a bounded polyhedron described by finitely many linear inequalities. We provide a lower bound for…

Machine Learning · Computer Science 2015-09-29 Manjesh K. Hanawal , Amir Leshem , Venkatesh Saligrama

The optimization of black-box functions with noisy observations is a fundamental problem with widespread applications, and has been widely studied under the assumption that the function lies in a reproducing kernel Hilbert space (RKHS).…

Machine Learning · Statistics 2025-02-11 Xu Cai , Jonathan Scarlett

Black box optimisation of an unknown function from expensive and noisy evaluations is a ubiquitous problem in machine learning, academic research and industrial production. An abstraction of the problem can be formulated as a kernel based…

Machine Learning · Statistics 2023-02-02 Sattar Vakili , Danyal Ahmed , Alberto Bernacchia , Ciara Pike-Burke

We consider the problem of stochastic $K$-armed dueling bandit in the contextual setting, where at each round the learner is presented with a context set of $K$ items, each represented by a $d$-dimensional feature vector, and the goal of…

Machine Learning · Computer Science 2021-05-11 Aadirupa Saha , Aditya Gopalan

In this paper, we consider the time-varying Bayesian optimization problem. The unknown function at each time is assumed to lie in an RKHS (reproducing kernel Hilbert space) with a bounded norm. We adopt the general variation budget model to…

Machine Learning · Computer Science 2021-05-04 Xingyu Zhou , Ness Shroff

We tackle the problem of online reward maximisation over a large finite set of actions described by their contexts. We focus on the case when the number of actions is too big to sample all of them even once. However we assume that we have…

Machine Learning · Computer Science 2013-09-27 Michal Valko , Nathaniel Korda , Remi Munos , Ilias Flaounas , Nelo Cristianini

We study a constrained contextual linear bandit setting, where the goal of the agent is to produce a sequence of policies, whose expected cumulative reward over the course of $T$ rounds is maximum, and each has an expected cost below a…

Machine Learning · Computer Science 2020-06-20 Aldo Pacchiano , Mohammad Ghavamzadeh , Peter Bartlett , Heinrich Jiang

We consider the problem of optimising functions in the reproducing kernel Hilbert space (RKHS) of a Mat\'ern kernel with smoothness parameter $\nu$ over the domain $[0,1]^d$ under noisy bandit feedback. Our contribution, the $\pi$-GP-UCB…

Machine Learning · Computer Science 2023-02-28 David Janz , David R. Burt , Javier González

We develop a new approach to obtaining high probability regret bounds for online learning with bandit feedback against an adaptive adversary. While existing approaches all require carefully constructing optimistic and biased loss…

Machine Learning · Computer Science 2020-11-02 Chung-Wei Lee , Haipeng Luo , Chen-Yu Wei , Mengxiao Zhang

We consider the kernelized contextual bandit problem with a large feature space. This problem involves $K$ arms, and the goal of the forecaster is to maximize the cumulative rewards through learning the relationship between the contexts and…

Machine Learning · Statistics 2025-05-21 Shogo Iwazaki , Junpei Komiyama , Masaaki Imaizumi

We are interested in a framework of online learning with kernels for low-dimensional but large-scale and potentially adversarial datasets. We study the computational and theoretical performance of online variations of kernel Ridge…

Machine Learning · Statistics 2019-05-30 Rémi Jézéquel , Pierre Gaillard , Alessandro Rudi

We consider distributed kernel bandits where $N$ agents aim to collaboratively maximize an unknown reward function that lies in a reproducing kernel Hilbert space. Each agent sequentially queries the function to obtain noisy observations at…

Machine Learning · Computer Science 2024-02-21 Nikola Pavlovic , Sudeep Salgia , Qing Zhao

We revisit the problem of online learning with sleeping experts/bandits: in each time step, only a subset of the actions are available for the algorithm to choose from (and learn about). The work of Kleinberg et al. (2010) showed that there…

Machine Learning · Computer Science 2021-04-27 Ehsan Emamjomeh-Zadeh , Chen-Yu Wei , Haipeng Luo , David Kempe

Policy regret is a well established notion of measuring the performance of an online learning algorithm against an adaptive adversary. We study restrictions on the adversary that enable efficient minimization of the \emph{complete policy…

Machine Learning · Statistics 2022-04-26 Dhruv Malik , Yuanzhi Li , Aarti Singh

We study the adversarial bandit problem with composite anonymous delayed feedback. In this setting, losses of an action are split into $d$ components, spreading over consecutive rounds after the action is chosen. And in each round, the…

Machine Learning · Computer Science 2022-04-29 Zongqi Wan , Xiaoming Sun , Jialin Zhang

We consider model selection in stochastic bandit and reinforcement learning problems. Given a set of base learning algorithms, an effective model selection strategy adapts to the best learning algorithm in an online fashion. We show that by…

Machine Learning · Computer Science 2020-06-11 Yasin Abbasi-Yadkori , Aldo Pacchiano , My Phan

We present regret minimization algorithms for the contextual multi-armed bandit (CMAB) problem over $K$ actions in the presence of delayed feedback, a scenario where loss observations arrive with delays chosen by an adversary. As a…

Machine Learning · Computer Science 2025-10-13 Orin Levy , Liad Erez , Alon Cohen , Yishay Mansour

We present an efficient algorithm for linear contextual bandits with adversarial losses and stochastic action sets. Our approach reduces this setting to misspecification-robust adversarial linear bandits with fixed action sets. Without…

Machine Learning · Computer Science 2025-12-16 Tim van Erven , Jack Mayo , Julia Olkhovskaya , Chen-Yu Wei

We study online learning with bandit feedback (i.e. learner has access to only zeroth-order oracle) where cost/reward functions $\f_t$ admit a "pseudo-1d" structure, i.e. $\f_t(\w) = \loss_t(\pred_t(\w))$ where the output of $\pred_t$ is…

Machine Learning · Computer Science 2021-02-16 Aadirupa Saha , Nagarajan Natarajan , Praneeth Netrapalli , Prateek Jain