Implicit Feedbacks are Not Always Favorable: Iterative Relabeled One-Class Collaborative Filtering against Noisy Interactions

Due to privacy concerns, there is a rising favor in Recommender System community for the One-class Collaborative Filtering (OCCF) framework, which predicts user preferences only based on binary implicit feedback (e.g., click or not-click, rated or unrated). The major challenge in OCCF problem stems from the inherent noise in implicit interaction. Previous approaches have taken into account the noise in unobserved interactions (i.e., not-click only means a missing value, rather than negative feedback). However, they generally ignore the noise in observed interactions (i.e., click does not necessarily represent positive feedback), which might induce performance degradation. To attack this issue, we propose a novel iteratively relabeling framework to jointly mitigate the noise in both observed and unobserved interactions. As the core of the framework, the iterative relabeling module exploits the self-training principle to dynamically generate pseudo labels for user preferences. The downstream module for a recommendation task is then trained with the refreshed labels where the noisy patterns are largely alleviated. Finally, extensive experiments on three real-world datasets demonstrate the effectiveness of our proposed methods.