Temporal Graph ODEs for Irregularly-Sampled Time Series

Alessio Gravina, Daniele Zambon, Davide Bacciu and Cesare Alippi, Temporal Graph ODEs for Irregularly-Sampled Time Series, in Proceedings of the Thirty-Third International Joint Conference on Artificial Intelligence, IJCAI-24, 4025-4034, doi: 10.24963/ijcai.2024/445.

Abstract: Modern graph representation learning works mostly under the assumption of dealing with regularly sampled temporal graph snapshots, which is far from realistic, e.g., social networks and physical systems are characterized by continuous dynamics and sporadic observations. To address this limitation, we introduce the Temporal Graph Ordinary Differential Equation (TG-ODE) framework, which learns both the temporal and spatial dynamics from graph streams where the intervals between observations are not regularly spaced. We empirically validate the proposed approach on several graph benchmarks, showing that TG-ODE can achieve state-of-the-art performance in irregular graph stream tasks.