Meta Clustering of Neural Bandits
This work addresses the challenge of improving online recommendation and classification performance by dynamically clustering users, though it appears incremental as it builds on prior neural bandit methods.
The paper tackles the problem of balancing user heterogeneity and correlations in recommender systems by extending neural bandits to arbitrary reward functions, and proposes M-CNB, a meta-learning algorithm that outperforms state-of-the-art baselines in experiments.
The contextual bandit has been identified as a powerful framework to formulate the recommendation process as a sequential decision-making process, where each item is regarded as an arm and the objective is to minimize the regret of $T$ rounds. In this paper, we study a new problem, Clustering of Neural Bandits, by extending previous work to the arbitrary reward function, to strike a balance between user heterogeneity and user correlations in the recommender system. To solve this problem, we propose a novel algorithm called M-CNB, which utilizes a meta-learner to represent and rapidly adapt to dynamic clusters, along with an informative Upper Confidence Bound (UCB)-based exploration strategy. We provide an instance-dependent performance guarantee for the proposed algorithm that withstands the adversarial context, and we further prove the guarantee is at least as good as state-of-the-art (SOTA) approaches under the same assumptions. In extensive experiments conducted in both recommendation and online classification scenarios, M-CNB outperforms SOTA baselines. This shows the effectiveness of the proposed approach in improving online recommendation and online classification performance.