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arXiv · 1807.03558

Bandits with Side Observations: Bounded vs. Logarithmic Regret

Rémy Degenne·Evrard Garcelon·Vianney Perchet
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Abstract

We consider the classical stochastic multi-armed bandit but where, from time to time and roughly with frequency $\epsilon$, an extra observation is gathered by the agent for free. We prove that, no matter how small $\epsilon$ is the agent can ensure a regret uniformly bounded in time. More precisely, we construct an algorithm with a regret smaller than $\sum_i \frac{\log(1/\epsilon)}{\Delta_i}$, up to multiplicative constant and loglog terms. We also prove a matching lower-bound, stating that no reasonable algorithm can outperform this quantity.

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Rémy Degenne, Evrard Garcelon, Vianney Perchet. 2018-07-10. Bandits with Side Observations: Bounded vs. Logarithmic Regret. https://arxiv.org/abs/1807.03558

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