Multi-Class Traffic Assignment using Multi-View Heterogeneous Graph Attention Networks

TL;DR

This paper introduces a novel heterogeneous graph neural network model with multi-view attention for multi-class traffic assignment, significantly improving prediction accuracy and convergence speed over traditional methods.

Contribution

It develops a new surrogate model using multi-view heterogeneous graph attention networks that incorporate flow conservation for multi-class traffic assignment.

Findings

Outperforms traditional neural networks in accuracy

Achieves faster convergence in traffic prediction

Effective in both user equilibrium and system optimal scenarios

Abstract

Solving traffic assignment problem for large networks is computationally challenging when conventional optimization-based methods are used. In our research, we develop an innovative surrogate model for a traffic assignment when multi-class vehicles are involved. We do so by employing heterogeneous graph neural networks which use a multiple-view graph attention mechanism tailored to different vehicle classes, along with additional links connecting origin-destination pairs. We also integrate the node-based flow conservation law into the loss function. As a result, our model adheres to flow conservation while delivering highly accurate predictions for link flows and utilization ratios. Through numerical experiments conducted on urban transportation networks, we demonstrate that our model surpasses traditional neural network approaches in convergence speed and predictive accuracy in both user equilibrium and system optimal versions of traffic assignment.