An Aggregate Urban Transportation Model: Econometric Specification.
While much previous transportation research has been devoted to estimating the user and socioeconomic impacts of routes, emerging problems seem to relate more to total volume of travel: improving air quality relates closely to total automobile and truck travel volumes; gasoline consumption is a function of total automobile and truck travel volumes; and travel volumes along particular routes are of little importance to energy problems. This paper derives a model of aggregate transportation relationships within an urban region. The model consists of two estimated equations and two equilibrium relations that can be used to determine vehicle miles, public transit trips, average public transit price, and public transit vehicle miles, if the marginal cost of public transit trips and vehicle miles is known. Cost information can be obtained by estimating a cost function for public transit firms. 29 pp. Bibliog.