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20152026
most citedOptimal Regret Analysis of Thompson Sampling in Stochastic Multi-armed Bandit Problem with Multiple Plays

70 citations · 161 across the 37 of their papers we have counts for

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Showing 2025Show all

5 papers · 1 filter

stat.ML2025

Rate-optimal Design for Anytime Best Arm Identification

Junpei Komiyama, Kyoungseok Jang, Junya Honda

We consider the best arm identification problem, where the goal is to identify the arm with the highest mean reward from a set of arms under a limited sampling budget. This pro…

stat.ML2025

Best-of- -- Asymptotic Performance of Test-Time LLM Ensembling

Junpei Komiyama, Daisuke Oba, Masafumi Oyamada

We study best-of- for large language models (LLMs) where the selection is based on majority voting. In particular, we analyze the limit , which we denote as \boinf…

stat.ML2025

High-dimensional Nonparametric Contextual Bandit Problem

Shogo Iwazaki, Junpei Komiyama, Masaaki Imaizumi

We consider the kernelized contextual bandit problem with a large feature space. This problem involves arms, and the goal of the forecaster is to maximize the cumulative reward…

cs.LG2025

No-regret incentive-compatible online learning under exact truthfulness with non-myopic experts

Junpei Komiyama, Nishant A. Mehta, Ali Mortazavi

We study an online forecasting setting in which, over rounds, strategic experts each report a forecast to a mechanism, the mechanism selects one forecast, and then the outc…

cs.LG2025

Data-dependent Bounds with -Optimal Best-of-Both-Worlds Guarantees in Multi-Armed Bandits using Stability-Penalty Matching

Quan Nguyen, Shinji Ito, Junpei Komiyama +1

Existing data-dependent and best-of-both-worlds regret bounds for multi-armed bandits problems have limited adaptivity as they are either data-dependent but not best-of-both-worlds…