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arXiv · 2308.07048

UIPC-MF: User-Item Prototype Connection Matrix Factorization for Explainable Collaborative Filtering

Abstract

Recommending items to potentially interested users has been an important commercial task that faces two main challenges: accuracy and explainability. While most collaborative filtering models rely on statistical computations on a large scale of interaction data between users and items and can achieve high performance, they often lack clear explanatory power. We propose UIPC-MF, a prototype-based matrix factorization method for explainable collaborative filtering recommendations. In UIPC-MF, both users and items are associated with sets of prototypes, capturing general collaborative attributes. To enhance explainability, UIPC-MF learns connection weights that reflect the associative relations between user and item prototypes for recommendations. UIPC-MF outperforms other prototype-based baseline methods in terms of Hit Ratio and Normalized Discounted Cumulative Gain on three datasets, while also providing better transparency.

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Lei Pan, Von-Wun Soo. 2023-08-14. UIPC-MF: User-Item Prototype Connection Matrix Factorization for Explainable Collaborative Filtering. https://doi.org/10.1007/978-981-97-2262-4_14

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