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Related papers: On the Prior Sensitivity of Thompson Sampling

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Stochastic rising rested bandit (SRRB) is a setting where the arms' expected rewards increase as they are pulled. It models scenarios in which the performances of the different options grow as an effect of an underlying learning process…

Machine Learning · Statistics 2025-05-21 Marco Fiandri , Alberto Maria Metelli , Francesco Trovò

We propose ${\tt AdaTS}$, a Thompson sampling algorithm that adapts sequentially to bandit tasks that it interacts with. The key idea in ${\tt AdaTS}$ is to adapt to an unknown task prior distribution by maintaining a distribution over its…

Machine Learning · Computer Science 2022-02-28 Soumya Basu , Branislav Kveton , Manzil Zaheer , Csaba Szepesvári

We study multi-armed bandit problems with graph feedback, in which the decision maker is allowed to observe the neighboring actions of the chosen action, in a setting where the graph may vary over time and is never fully revealed to the…

Machine Learning · Statistics 2018-05-24 Fang Liu , Zizhan Zheng , Ness Shroff

Thompson Sampling has been widely used for contextual bandit problems due to the flexibility of its modeling power. However, a general theory for this class of methods in the frequentist setting is still lacking. In this paper, we present a…

Machine Learning · Computer Science 2021-10-05 Tong Zhang

We propose algorithms based on a multi-level Thompson sampling scheme, for the stochastic multi-armed bandit and its contextual variant with linear expected rewards, in the setting where arms are clustered. We show, both theoretically and…

Machine Learning · Computer Science 2022-06-16 Emil Carlsson , Devdatt Dubhashi , Fredrik D. Johansson

Contextual bandits constitute a classical framework for decision-making under uncertainty. In this setting, the goal is to learn the arms of highest reward subject to contextual information, while the unknown reward parameters of each arm…

Machine Learning · Statistics 2024-02-19 Hongju Park , Mohamad Kazem Shirani Faradonbeh

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

We study a stochastic bandit algorithm motivated by retry-aware objectives that value the best outcome among multiple attempts, such as pass@$k$ and max@$k$. Given a posterior over arm values, ReMax chooses a sampling distribution that…

Machine Learning · Computer Science 2026-05-21 Bingkui Tong , Junpei Komiyama , Soichiro Nishimori , Paavo Parmas

In this work we first show that the classical Thompson sampling algorithm for multi-arm bandits is differentially private as-is, without any modification. We provide per-round privacy guarantees as a function of problem parameters and show…

Machine Learning · Computer Science 2024-07-23 Tingting Ou , Marco Avella Medina , Rachel Cummings

Thompson Sampling is one of the most effective methods for contextual bandits and has been generalized to posterior sampling for certain MDP settings. However, existing posterior sampling methods for reinforcement learning are limited by…

Machine Learning · Computer Science 2022-08-24 Christoph Dann , Mehryar Mohri , Tong Zhang , Julian Zimmert

We address multi-armed bandits (MAB) where the objective is to maximize the cumulative reward under a probabilistic linear constraint. For a few real-world instances of this problem, constrained extensions of the well-known Thompson…

Machine Learning · Computer Science 2020-05-14 Vidit Saxena , Joseph E. Gonzalez , Joakim Jaldén

In this paper, we study sequential decision-making for maximizing the Sharpe ratio (SR) in a stochastic multi-armed bandit (MAB) setting. Unlike standard bandit formulations that maximize cumulative reward, SR optimization requires…

Machine Learning · Computer Science 2026-04-02 Mohammad Taha Shah , Sabrina Khurshid , Gourab Ghatak

We discuss a multiple-play multi-armed bandit (MAB) problem in which several arms are selected at each round. Recently, Thompson sampling (TS), a randomized algorithm with a Bayesian spirit, has attracted much attention for its empirically…

Machine Learning · Statistics 2019-03-22 Junpei Komiyama , Junya Honda , Hiroshi Nakagawa

In the stochastic multi-armed bandit problem, a randomized probability matching policy called Thompson sampling (TS) has shown excellent performance in various reward models. In addition to the empirical performance, TS has been shown to…

Machine Learning · Computer Science 2023-02-06 Jongyeong Lee , Junya Honda , Chao-Kai Chiang , Masashi Sugiyama

This paper studies the stochastic linear bandit problem, where a decision-maker chooses actions from possibly time-dependent sets of vectors in $\mathbb{R}^d$ and receives noisy rewards. The objective is to minimize regret, the difference…

Machine Learning · Computer Science 2023-04-24 Nima Hamidi , Mohsen Bayati

We study the Thompson sampling algorithm in an adversarial setting, specifically, for adversarial bit prediction. We characterize the bit sequences with the smallest and largest expected regret. Among sequences of length $T$ with $k <…

Machine Learning · Computer Science 2020-01-01 Yuval Lewi , Haim Kaplan , Yishay Mansour

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

In this work, we study the performance of the Thompson Sampling algorithm for Contextual Bandit problems based on the framework introduced by Neu et al. and their concept of lifted information ratio. First, we prove a comprehensive bound on…

Machine Learning · Statistics 2023-04-27 Amaury Gouverneur , Borja Rodríguez-Gálvez , Tobias J. Oechtering , Mikael Skoglund

We study a cooperative multi-agent multi-armed bandits with M agents and K arms. The goal of the agents is to minimized the cumulative regret. We adapt a traditional Thompson Sampling algoirthm under the distributed setting. However, with…

Artificial Intelligence · Computer Science 2021-09-10 Jing Dong , Tan Li , Shaolei Ren , Linqi Song

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