Most existing urban truck-travel demand-forecasting techniques stratify truck trips into only two categories for modeling purposes--trips made by light trucks and trips made by heavy trucks. The rationale behind this stratification is that the trip-making characteristics of the two truck types are quite different and thus should be analyzed independently. The purpose of this research was to determine whether additional stratification of truck trips aids in improving the reliability of truck trip forecasts. Several additional stratifications were considered, including stratifications by vehicle type, trip purpose, and destination land use. Comparisons of truck trips stratified by vehicle type for three cities showed no improvement due to the stratifications. In general, the overall unstratified models were more statistically adequate, and the independent variables that were most significant in the stratified equations were comparable with those that appeared in the total truck model. Similar results were obtained when total internal truck trips were stratified according to trip purpose. The stratifications by trip purpose did show, however, that goods-related trips have a strong relationship with either commercial or retail employment, while service-type trips are most strongly related to measures of total employment. Results from the stratification by land use at destination, in which total truck trip ends were categorized as either industrial trips (those made to various types of industrial and manufacturing land uses) or consumer-related trips (those made to land uses associated with the resident population of a study area), showed some improvement over the more general overall models. In two of the three case studies, in fact, significant differences were noted between the stratified and unstratified results, in terms of both the types of independent variables employed and the statistical reliability of the regression equations themselves. (Author)

Media Info

  • Media Type: Print
  • Features: References; Tables;
  • Pagination: pp 1-6
  • Monograph Title: Advances in urban transportation planning
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00334150
  • Record Type: Publication
  • ISBN: 030903115X
  • Files: TRIS, TRB
  • Created Date: Oct 28 1981 12:00AM