Title
MixGCF: An Improved Training Method for Graph Neural Network-based Recommender Systems
Abstract
ABSTRACTGraph neural networks (GNNs) have recently emerged as state-of-the-art collaborative filtering (CF) solution. A fundamental challenge of CF is to distill negative signals from the implicit feedback, but negative sampling in GNN-based CF has been largely unexplored. In this work, we propose to study negative sampling by leveraging both the user-item graph structure and GNNs' aggregation process. We present the MixGCF method---a general negative sampling plugin that can be directly used to train GNN-based recommender systems. In MixGCF, rather than sampling raw negatives from data, we design the hop mixing technique to synthesize hard negatives. Specifically, the idea of hop mixing is to generate the synthetic negative by aggregating embeddings from different layers of raw negatives' neighborhoods. The layer and neighborhood selection process are optimized by a theoretically-backed hard selection strategy. Extensive experiments demonstrate that by using MixGCF, state-of-the-art GNN-based recommendation models can be consistently and significantly improved, e.g., 26% for NGCF and 22% for LightGCN in terms of [email protected]
Year
DOI
Venue
2021
10.1145/3447548.3467408
Knowledge Discovery and Data Mining
Keywords
DocType
Citations 
Collaborative Filtering, Recommender Systems, Graph Neural Networks, Negative Sampling
Conference
2
PageRank 
References 
Authors
0.36
26
7
Name
Order
Citations
PageRank
Tinglin Huang141.14
Yuxiao Dong291946.41
Ming Ding3777.20
Zhen Yang420.70
Wenzheng Feng531.41
xinyu659030.19
Jie Tang75871300.22