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arXiv · 1902.07500

A Note on Bounding Regret of the C$^2$UCB Contextual Combinatorial Bandit

Bastian Oetomo·Malinga Perera·Renata Borovica-Gajic·Benjamin I. P. Rubinstein
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Abstract

We revisit the proof by Qin et al. (2014) of bounded regret of the C$^2$UCB contextual combinatorial bandit. We demonstrate an error in the proof of volumetric expansion of the moment matrix, used in upper bounding a function of context vector norms. We prove a relaxed inequality that yields the originally-stated regret bound.

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Bastian Oetomo, Malinga Perera, Renata Borovica-Gajic, Benjamin I. P. Rubinstein. 2019-02-20. A Note on Bounding Regret of the C$^2$UCB Contextual Combinatorial Bandit. https://arxiv.org/abs/1902.07500

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