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arXiv · 2305.04093

An improved regret analysis for UCB-N and TS-N

Nishant A. Mehta
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Abstract

In the setting of stochastic online learning with undirected feedback graphs, Lykouris et al. (2020) previously analyzed the pseudo-regret of the upper confidence bound-based algorithm UCB-N and the Thompson Sampling-based algorithm TS-N. In this note, we show how to improve their pseudo-regret analysis. Our improvement involves refining a key lemma of the previous analysis, allowing a $\log(T)$ factor to be replaced by a factor $\log_2(\alpha) + 3$ for $\alpha$ the independence number of the feedback graph.

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Nishant A. Mehta. 2023-05-06. An improved regret analysis for UCB-N and TS-N. https://arxiv.org/abs/2305.04093

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