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arXiv · 2410.03954

SDA-GRIN for Adaptive Spatial-Temporal Multivariate Time Series Imputation

Amir Eskandari·Aman Anand·Drishti Sharma·Farhana Zulkernine
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Abstract

In various applications, the multivariate time series often suffers from missing data. This issue can significantly disrupt systems that rely on the data. Spatial and temporal dependencies can be leveraged to impute the missing samples. Existing imputation methods often ignore dynamic changes in spatial dependencies. We propose a Spatial Dynamic Aware Graph Recurrent Imputation Network (SDA-GRIN) which is capable of capturing dynamic changes in spatial dependencies.SDA-GRIN leverages a multi-head attention mechanism to adapt graph structures with time. SDA-GRIN models multivariate time series as a sequence of temporal graphs and uses a recurrent message-passing architecture for imputation. We evaluate SDA-GRIN on four real-world datasets: SDA-GRIN improves MSE by 9.51% for the AQI and 9.40% for AQI-36. On the PEMS-BAY dataset, it achieves a 1.94% improvement in MSE. Detailed ablation study demonstrates the effect of window sizes and missing data on the performance of the method. Project page:https://ameskandari.github.io/sda-grin/

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Amir Eskandari, Aman Anand, Drishti Sharma, Farhana Zulkernine. 2024-10-04. SDA-GRIN for Adaptive Spatial-Temporal Multivariate Time Series Imputation. https://arxiv.org/abs/2410.03954

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