A Multi-Channel Spatial-Temporal Transformer Model for Traffic Flow Forecasting
Jianli Xiao, Baichao Long
TL;DR
The paper tackles robust traffic flow forecasting by addressing long-horizon degradation and complex spatio-temporal dependencies. It introduces MC-STTM, a multi-channel spatial-temporal Transformer that fuses short-term and daily patterns through a multi-channel mechanism, while a spatial block combines adaptive and fixed graph structures with a Transformer for temporal reasoning. Key innovations include learning a dynamic adjacency via $A_{adp}$ alongside distance-based fixed graphs, and a weekday-aware position encoding within the Temporal Transformer. Experiments on six real-world datasets show MC-STTM consistently outperforms state-of-the-art baselines, with strong long-term predictive performance and resilience to noise, suggesting practical value for urban traffic management and planning.
Abstract
Traffic flow forecasting is a crucial task in transportation management and planning. The main challenges for traffic flow forecasting are that (1) as the length of prediction time increases, the accuracy of prediction will decrease; (2) the predicted results greatly rely on the extraction of temporal and spatial dependencies from the road networks. To overcome the challenges mentioned above, we propose a multi-channel spatial-temporal transformer model for traffic flow forecasting, which improves the accuracy of the prediction by fusing results from different channels of traffic data. Our approach leverages graph convolutional network to extract spatial features from each channel while using a transformer-based architecture to capture temporal dependencies across channels. We introduce an adaptive adjacency matrix to overcome limitations in feature extraction from fixed topological structures. Experimental results on six real-world datasets demonstrate that introducing a multi-channel mechanism into the temporal model enhances performance and our proposed model outperforms state-of-the-art models in terms of accuracy.
