Latent Processes Identification From Multi-View Time Series

Latent Processes Identification From Multi-View Time Series

Zenan Huang, Haobo Wang, Junbo Zhao, Nenggan Zheng

Proceedings of the Thirty-Second International Joint Conference on Artificial Intelligence
Main Track. Pages 3848-3856. https://doi.org/10.24963/ijcai.2023/428

Understanding the dynamics of time series data typically requires identifying the unique latent factors for data generation, a.k.a., latent processes identification. Driven by the independent assumption, existing works have made great progress in handling single-view data. However, it is a non-trivial problem that extends them to multi-view time series data because of two main challenges: (i) the complex data structure, such as temporal dependency, can result in violation of the independent assumption; (ii) the factors from different views are generally overlapped and are hard to be aggregated to a complete set. In this work, we propose a novel framework MuLTI that employs the contrastive learning technique to invert the data generative process for enhanced identifiability. Additionally, MuLTI integrates a permutation mechanism that merges corresponding overlapped variables by the establishment of an optimal transport formula. Extensive experimental results on synthetic and real-world datasets demonstrate the superiority of our method in recovering identifiable latent variables on multi-view time series. The code is available on https://github.com/lccurious/MuLTI.
Keywords:
Machine Learning: ML: Causality
Machine Learning: ML: Multi-view learning