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Title: Neighborhood-aware Scalable Temporal Network Representation Learning
Temporal networks have been widely used to model real-world complex systems such as financial systems and e-commerce systems. In a temporal network, the joint neighborhood of a set of nodes often provides crucial structural information useful for predicting whether they may interact at a certain time. However, recent representation learning methods for temporal networks often fail to extract such information or depend on online construction of structural features, which is time-consuming. To address the issue, this work proposes Neighborhood-Aware Temporal network model (NAT). For each node in the network, NAT abandons the commonly-used one-single-vector-based representation while adopting a novel dictionary-type neighborhood representation. Such a dictionary representation records a downsampled set of the neighboring nodes as keys, and allows fast construction of structural features for a joint neighborhood of multiple nodes. We also design a dedicated data structure termed N-cache to support parallel access and update of those dictionary representations on GPUs. NAT gets evaluated over seven real-world large-scale temporal networks. NAT not only outperforms all cutting-edge baselines by averaged 1.2% and 4.2% in transductive and inductive link prediction accuracy, respectively, but also keeps scalable by achieving a speed-up of 4.1-76.7x against the baselines that adopt joint structural features and achieves a speed-up of 1.6-4.0x against the baselines that cannot adopt those features. The link to the code: https: //github.com/Graph-COM/Neighborhood-Aware-Temporal-Network. https://arxiv.org/abs/2209.01084 https://proceedings.mlr.press/v198/luo22a.html  more » « less
Award ID(s):
2117997
NSF-PAR ID:
10422137
Author(s) / Creator(s):
;
Editor(s):
Rieck, Bastian and
Date Published:
Journal Name:
Neighborhood-aware Scalable Temporal Network Representation Learning
Volume:
198
Page Range / eLocation ID:
1-18
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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