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Related papers: Dealing with Unknown Variances in Best-Arm Identif…

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In this paper, we study the tradeoffs between the time and the number of communication rounds of the best arm identification problem in the heterogeneous collaborative learning model, where multiple agents interact with possibly different…

Machine Learning · Computer Science 2024-04-19 Nikolai Karpov , Qin Zhang

The question of selecting the "best" amongst different choices is a common problem in statistics. In drug development, our motivating setting, the question becomes, for example: what is the dose that gives me a pre-specified risk of…

Statistics Theory · Mathematics 2018-03-15 Pavel Mozgunov , Thomas Jaki

Recently multi-armed bandit problem arises in many real-life scenarios where arms must be sampled in batches, due to limited time the agent can wait for the feedback. Such applications include biological experimentation and online…

Machine Learning · Statistics 2023-12-22 Shengyu Cao , Simai He , Ruoqing Jiang , Jin Xu , Hongsong Yuan

Recent work has considered natural variations of the multi-armed bandit problem, where the reward distribution of each arm is a special function of the time passed since its last pulling. In this direction, a simple (yet widely applicable)…

Machine Learning · Computer Science 2021-05-25 Alexia Atsidakou , Orestis Papadigenopoulos , Soumya Basu , Constantine Caramanis , Sanjay Shakkottai

Motivated by the task of hyperparameter optimization, we introduce the non-stochastic best-arm identification problem. Within the multi-armed bandit literature, the cumulative regret objective enjoys algorithms and analyses for both the…

Machine Learning · Computer Science 2015-03-02 Kevin Jamieson , Ameet Talwalkar

Stochastic Rising Bandits (SRBs) model sequential decision-making problems in which the expected reward of the available options increases every time they are selected. This setting captures a wide range of scenarios in which the available…

Machine Learning · Computer Science 2024-05-29 Marco Mussi , Alessandro Montenegro , Francesco Trovó , Marcello Restelli , Alberto Maria Metelli

In this study, we develop a stochastic optimal control approach with reinforcement learning structure to learn the unknown parameters appeared in the drift and diffusion terms of the stochastic differential equation. By choosing an…

Optimization and Control · Mathematics 2023-08-22 Shuzhen Yang

Pandemic influenza has the epidemic potential to kill millions of people. While various preventive measures exist (i.a., vaccination and school closures), deciding on strategies that lead to their most effective and efficient use remains…

Machine Learning · Computer Science 2018-06-18 Pieter Libin , Timothy Verstraeten , Diederik M. Roijers , Jelena Grujic , Kristof Theys , Philippe Lemey , Ann Nowé

In fixed-confidence best arm identification (BAI), the objective is to quickly identify the optimal option while controlling the probability of error below a desired threshold. Despite the plethora of BAI algorithms, existing methods…

Machine Learning · Computer Science 2026-01-05 Brian M. Cho , Nathan Kallus

This paper introduces a novel Bayesian approach to detect changes in the variance of a Gaussian sequence model, focusing on quantifying the uncertainty in the change point locations and providing a scalable algorithm for inference. Such a…

Methodology · Statistics 2025-03-04 Lorenzo Cappello , Oscar Hernan Madrid Padilla

Reward models (RMs) are essential for aligning large language models (LLM) with human expectations. However, existing RMs struggle to capture the stochastic and uncertain nature of human preferences and fail to assess the reliability of…

Machine Learning · Computer Science 2025-02-13 Xingzhou Lou , Dong Yan , Wei Shen , Yuzi Yan , Jian Xie , Junge Zhang

We present a two-armed bandit model of decision making under uncertainty where the expected return to investing in the "risky arm" increases when choosing that arm and decreases when choosing the "safe" arm. These dynamics are natural in…

Optimization and Control · Mathematics 2017-03-22 Roland Fryer , Philipp Harms

In the classic multi-armed bandits problem, the goal is to have a policy for dynamically operating arms that each yield stochastic rewards with unknown means. The key metric of interest is regret, defined as the gap between the expected…

Optimization and Control · Mathematics 2010-11-23 Yi Gai , Bhaskar Krishnamachari , Rahul Jain

Decision making under uncertain environments in the maximization of expected reward while minimizing its risk is one of the ubiquitous problems in many subjects. Here, we introduce a novel problem setting in stochastic bandit optimization…

Machine Learning · Computer Science 2025-10-27 Shunta Nonaga , Koji Tabata , Yuta Mizuno , Tamiki Komatsuzaki

The study of model bias and variance with respect to decision boundaries is critically important in supervised classification. There is generally a tradeoff between the two, as fine-tuning of the decision boundary of a classification model…

Machine Learning · Computer Science 2020-02-25 Matthew Almeida , Wei Ding , Scott Crouter , Ping Chen

We lay the foundations of a non-parametric theory of best-arm identification in multi-armed bandits with a fixed budget T. We consider general, possibly non-parametric, models D for distributions over the arms; an overarching example is the…

Machine Learning · Computer Science 2023-02-07 Antoine Barrier , Aurélien Garivier , Gilles Stoltz

Given a finite set of unknown distributions or arms that can be sampled, we consider the problem of identifying the one with the maximum mean using a $\delta$-correct algorithm (an adaptive, sequential algorithm that restricts the…

Machine Learning · Computer Science 2023-11-27 Shubhada Agrawal , Sandeep Juneja , Peter Glynn

We consider a novel stochastic multi-armed bandit setting, where playing an arm makes it unavailable for a fixed number of time slots thereafter. This models situations where reusing an arm too often is undesirable (e.g. making the same…

Machine Learning · Computer Science 2024-07-31 Soumya Basu , Rajat Sen , Sujay Sanghavi , Sanjay Shakkottai

In this paper, we consider a new Multi-Armed Bandit (MAB) problem where arms are nodes in an unknown and possibly changing graph, and the agent (i) initiates random walks over the graph by pulling arms, (ii) observes the random walk…

Machine Learning · Computer Science 2022-06-28 Tianyu Wang , Lin F. Yang , Zizhuo Wang

The classical multi-armed bandit (MAB) problem involves a learner and a collection of K independent arms, each with its own ex ante unknown independent reward distribution. At each one of a finite number of rounds, the learner selects one…

Optimization and Control · Mathematics 2024-05-07 Hongda Hu , Arthur Charpentier , Mario Ghossoub , Alexander Schied