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Related papers: MOTS: Minimax Optimal Thompson Sampling

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In this paper we consider the contextual multi-armed bandit problem for linear payoffs under a risk-averse criterion. At each round, contexts are revealed for each arm, and the decision maker chooses one arm to pull and receives the…

Machine Learning · Computer Science 2022-06-28 Yifan Lin , Yuhao Wang , Enlu Zhou

Thompson Sampling has recently been shown to be optimal in the Bernoulli Multi-Armed Bandit setting[Kaufmann et al., 2012]. This bandit problem assumes stationary distributions for the rewards. It is often unrealistic to model the real…

Machine Learning · Computer Science 2013-02-18 Joseph Mellor , Jonathan Shapiro

Thompson sampling (TS) has been known for its outstanding empirical performance supported by theoretical guarantees across various reward models in the classical stochastic multi-armed bandit problems. Nonetheless, its optimality is often…

Machine Learning · Computer Science 2023-12-14 Jongyeong Lee , Chao-Kai Chiang , Masashi Sugiyama

In this paper we consider Thompson Sampling (TS) for combinatorial semi-bandits. We demonstrate that, perhaps surprisingly, TS is sub-optimal for this problem in the sense that its regret scales exponentially in the ambient dimension, and…

Machine Learning · Statistics 2021-10-22 Raymond Zhang , Richard Combes

We give nearly-tight upper and lower bounds for the improving multi-armed bandits problem. An instance of this problem has $k$ arms, each of whose reward function is a concave and increasing function of the number of times that arm has been…

Machine Learning · Computer Science 2024-04-02 Avrim Blum , Kavya Ravichandran

Thompson sampling is an algorithm for online decision problems where actions are taken sequentially in a manner that must balance between exploiting what is known to maximize immediate performance and investing to accumulate new information…

Machine Learning · Computer Science 2020-07-16 Daniel Russo , Benjamin Van Roy , Abbas Kazerouni , Ian Osband , Zheng Wen

In linear contextual bandits, the objective is to select actions that maximize cumulative rewards, modeled as a linear function with unknown parameters. Although Thompson Sampling performs well empirically, it does not achieve optimal…

Machine Learning · Statistics 2025-06-18 Wonyoung Kim

In stochastic bandit problems, a Bayesian policy called Thompson sampling (TS) has recently attracted much attention for its excellent empirical performance. However, the theoretical analysis of this policy is difficult and its asymptotic…

Statistics Theory · Mathematics 2013-11-11 Junya Honda , Akimichi Takemura

The Bayesian paradigm offers principled tools for sequential decision-making under uncertainty, but its reliance on a probabilistic model for all parameters can hinder the incorporation of complex structural constraints. We introduce a…

Machine Learning · Computer Science 2025-10-09 Kaizheng Wang

We study the process-level dynamics of Thompson sampling and related sampling-based bandit algorithms in the ``small gap'' regime, where the gaps between the arm means are of order $\sqrt{\gamma}$ or smaller and the time horizon is of order…

Machine Learning · Computer Science 2026-04-23 Lin Fan , Peter W. Glynn

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

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

The problem of two-sided matching markets has a wide range of real-world applications and has been extensively studied in the literature. A line of recent works have focused on the problem setting where the preferences of one-side market…

Machine Learning · Computer Science 2022-05-03 Fang Kong , Junming Yin , Shuai Li

We provide an approach for the analysis of randomised exploration algorithms like Thompson sampling that does not rely on forced optimism or posterior inflation. With this, we demonstrate that in the $d$-dimensional linear bandit setting,…

Machine Learning · Computer Science 2025-02-14 Marc Abeille , David Janz , Ciara Pike-Burke

In this paper we study a multi-arm bandit problem in which the quality of each arm is measured by the Conditional Value at Risk (CVaR) at some level alpha of the reward distribution. While existing works in this setting mainly focus on…

Machine Learning · Computer Science 2022-03-22 Dorian Baudry , Romain Gautron , Emilie Kaufmann , Odalric-Ambryn Maillard

As the cornerstone of modern portfolio theory, Markowitz's mean-variance optimization is considered a major model adopted in portfolio management. However, due to the difficulty of estimating its parameters, it cannot be applied to all…

Machine Learning · Computer Science 2019-11-15 Mengying Zhu , Xiaolin Zheng , Yan Wang , Yuyuan Li , Qianqiao Liang

This paper presents a new approach for batch Bayesian Optimization (BO) called Thompson Sampling-Regret to Sigma Ratio directed sampling (TS-RSR), where we sample a new batch of actions by minimizing a Thompson Sampling approximation of a…

Machine Learning · Computer Science 2025-06-10 Zhaolin Ren , Na Li

Meta-learning is characterized by its ability to learn how to learn, enabling the adaptation of learning strategies across different tasks. Recent research introduced the Meta-Thompson Sampling (Meta-TS), which meta-learns an unknown prior…

Machine Learning · Statistics 2024-09-12 Hao Li , Dong Liang , Zheng Xie

In several applications of the stochastic multi-armed bandit problem, the traditional objective of maximizing the expected total reward can be inappropriate. In this paper, motivated by certain operational concerns in online platforms, we…

Machine Learning · Computer Science 2024-10-16 Eren Ozbay , Vijay Kamble

We consider incentivized exploration: a version of multi-armed bandits where the choice of arms is controlled by self-interested agents, and the algorithm can only issue recommendations. The algorithm controls the flow of information, and…

Computer Science and Game Theory · Computer Science 2022-06-14 Mark Sellke , Aleksandrs Slivkins