Joint Graph Contextualized Network for Sequential Recommendation

Abstract

Sequential recommendation aims to suggest items to users based on sequential dependencies. Graph neural networks (GNNs) are recently proposed to capture transitions of items by treating session sequences as graph-structured data. However, existing graph construction approaches mainly focus on the directional dependency of items and ignore benefits of feature aggregation from undirectional relationship. In this paper, we innovatively propose a joint graph contextualized network (JGCN) for sequential recommendation, which constructs both the directed graphs and undirected graphs to jointly capture current interests and global preferences. Specifically, we introduce gate graph neural networks and model the combined embedding of weighted position and node information from directed graphs for capturing current interests. Besides, to learn global preferences, we propose a graph collaborative attention network with correlation-based similarity of items from undirected graphs. Finally, a feed-forward layer with the residual connection is applied to synthetically obtain accurate transitions of items. Extensive experiments conducted on three datasets show that JGCN outperforms state-of-the-art methods.

Supported by the National Natural Science Foundation of China (NSFC) under Grant No. 61672498.