Regional Travel Patterns of a Small Metropolitan Area : Technical Paper

Abstract

The purpose of this study was to determine the factors that generate highway travel between the central city of a region and the communities in its surrounding zone of influence. The central city, Fort Wayne, Indiana, depends on the people in the smaller communities to sustain its regional facilities. In the same manner, these smaller cities depend upon the central city for various needs. This interdependence that produces and attracts these traffic movements was analyzed in this investigation. This development of regional travel patterns included the modeling of trips attracted to and trips produced by the central city. The basic form of the regression equations used to describe this flow of traffic was the gravity model; that is, trip production or attraction is directly proportional to the product of a given mass function of the two cities and inversely proportional to some power of the distance between these communities. Internal and external competition factors were introduced into the models to describe more completely the variations in regional trip generation and distribution. The separation of trips into specific trip purpose categories (work, shopping, social-recreational, and all-purpose) and travel types (produced and attracted) provided better estimation models. In addition, the division of the total study region into core and fringe areas demonstrated that the internal competition within a city had a negative effect on trip generation throughout the study region. However, the external competition of other cities was only significant in reducing trip generation for communities in the fringe area. A total of 24 statistical models was developed to describe the various arrangements of trip purpose, travel type, and area designation.