Microscopic simulation models, especially those that combine routing logic with detailed modeling of traffic flow dynamics, have vastly untapped the potential for modeling large-scale transportation networks. Building and calibrating such models could be quite challenging and is currently not widely understood. This paper describes the process of developing and calibrating a large scale microscopic model of Chittenden County, Vermont, a transportation system that represents an area of more than 540 square miles. The model used in the study is PARAMICS version 5.0, developed by Quadstone, Limited of the United Kingdom. Following a brief description of how the network was coded and the traffic demand specified, the paper discusses the process of error checking and routing logic calibration. Preliminary calibration results are encouraging, given the complexity of the model. The paper concludes by summarizing the main lessons learned and pointing out modeling pitfalls that should be avoided.
Abstract