Title
How Powerful is Graph Convolution for Recommendation?
Abstract
ABSTRACTGraph convolutional networks (GCNs) have recently enabled a popular class of algorithms for collaborative filtering (CF). Nevertheless, the theoretical underpinnings of their empirical successes remain elusive. In this paper, we endeavor to obtain a better understanding of GCN-based CF methods via the lens of graph signal processing. By identifying the critical role of smoothness, a key concept in graph signal processing, we develop a unified graph convolution-based framework for CF. We prove that many existing CF methods are special cases of this framework, including the neighborhood-based methods, low-rank matrix factorization, linear auto-encoders, and LightGCN, corresponding to different low-pass filters. Based on our framework, we then present a simple and computationally efficient CF baseline, which we shall refer to as Graph Filter based Collaborative Filtering (GF-CF). Given an implicit feedback matrix, GF-CF can be obtained in a closed form instead of expensive training with back-propagation. Experiments will show that GF-CF achieves competitive or better performance against deep learning-based methods on three well-known datasets, notably with a 70% performance gain over LightGCN on the Amazon-book dataset.
Year
DOI
Venue
2021
10.1145/3459637.3482264
Conference on Information and Knowledge Management
DocType
Citations 
PageRank 
Conference
5
0.40
References 
Authors
0
7
Name
Order
Citations
PageRank
Yifei Shen151.07
Yongji Wu250.40
Yao Zhang351.41
Caihua Shan452.42
Jun Zhang53772190.36
K. B. Letaief611078879.10
Dongsheng Li750.40