Parallel Knowledge Enhancement based Framework for Multi-behavior Recommendation

TL;DR

This paper introduces a novel framework called PKEF that improves multi-behavior recommendation by addressing data imbalance and negative transfer issues through parallel knowledge propagation and a projection mechanism.

Contribution

The paper proposes a parallel knowledge enhancement framework with modules to improve hierarchical information propagation and reduce negative transfer in multi-behavior recommendation models.

Findings

PKEF outperforms baseline models on three real-world datasets.

The PKF module enhances hierarchical information propagation.

The PME module effectively reduces negative transfer.

Abstract

Multi-behavior recommendation algorithms aim to leverage the multiplex interactions between users and items to learn users' latent preferences. Recent multi-behavior recommendation frameworks contain two steps: fusion and prediction. In the fusion step, advanced neural networks are used to model the hierarchical correlations between user behaviors. In the prediction step, multiple signals are utilized to jointly optimize the model with a multi-task learning (MTL) paradigm. However, recent approaches have not addressed the issue caused by imbalanced data distribution in the fusion step, resulting in the learned relationships being dominated by high-frequency behaviors. In the prediction step, the existing methods use a gate mechanism to directly aggregate expert information generated by coupling input, leading to negative information transfer. To tackle these issues, we propose a Parallel Knowledge Enhancement Framework (PKEF) for multi-behavior recommendation. Specifically, we enhance the hierarchical information propagation in the fusion step using parallel knowledge (PKF). Meanwhile, in the prediction step, we decouple the representations to generate expert information and introduce a projection mechanism during aggregation to eliminate gradient conflicts and alleviate negative transfer (PME). We conduct comprehensive experiments on three real-world datasets to validate the effectiveness of our model. The results further demonstrate the rationality and effectiveness of the designed PKF and PME modules. The source code and datasets are available at https://github.com/MC-CV/PKEF.