Online Semi-Supervised Learning in Contextual Bandits with Episodic Reward

Baihan Lin

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arXiv · 2009.08457

Online Semi-Supervised Learning in Contextual Bandits with Episodic Reward

Baihan Lin

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Abstract

We considered a novel practical problem of online learning with episodically revealed rewards, motivated by several real-world applications, where the contexts are nonstationary over different episodes and the reward feedbacks are not always available to the decision making agents. For this online semi-supervised learning setting, we introduced Background Episodic Reward LinUCB (BerlinUCB), a solution that easily incorporates clustering as a self-supervision module to provide useful side information when rewards are not observed. Our experiments on a variety of datasets, both in stationary and nonstationary environments of six different scenarios, demonstrated clear advantages of the proposed approach over the standard contextual bandit. Lastly, we introduced a relevant real-life example where this problem setting is especially useful.

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Baihan Lin. 2020-09-17. Online Semi-Supervised Learning in Contextual Bandits with Episodic Reward. https://arxiv.org/abs/2009.08457

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