MULTIMODAL LOGIT TRAVEL-DEMAND MODEL FOR SMALL AND MEDIUM-SIZED URBAN AREAS

The development and application of a one-step modal-split process that uses the logit approach and is oriented toward the needs and attributes of small and medium-sized urban areas are described. The essence of this study lies in the tailoring of commonly available aggregate (zonal) data for use in the disaggregate-based logit model, which is currently included in the Urban Transportation Planning System planning package. The development of work-trip and non-work-trip models is presented separately for the Flint urban area in Michigan. Each model studied the following five modes; (a) automobile, drive alone; (b) automobile, one passenger; (c) automobile, two passengers; (d) automobile, three or more passengers; and (e) transit, bus service. The results of the study indicate that the development of multimodal logit modal-split models is feasible by using aggregate data, and that the potential of applying this approach in other urban areas is quite high, although further calibration and validation efforts are needed before a more widespread application is practiced. The study also shows that, unlike traditional modal-split (diversion-curve-type) models, the resource requirements for these models are nominal and thus can be used for transportation planning purposes in small and medium-sized urban areas. The model is also sensitive to changes in transportation system attributes as well as in tripmaker characteristics and can be applied for testing air quality, energy, and other impacts of transportation strategies typical of smaller urban areas. (Author)