Policy relevance of transportation models
Transportation models, at least in the context of metropolitan-level planning, are implemented to inform decision-makers on a variety of issues. Modeling efforts are not, or should not be, undertaken in a vacuum without consideration of the ultimate use of the model.
Throughout most of their history, regional transportation models were designed to study the impacts of the provision of road and highway infrastructure on regional mobility. The early models were eventually upgraded to include the ability to forecast transit as well as auto modes.