Relationship is developed between the number of recreational vehicles and the average highway speed of all vehicles on a 4-lane interstate highway. The results suggest that recreational vehicles have a smaller impact on highway speeds than other large-sized vehicle classes containing trucks and buses. The speed reduction effect of recreational vehicles increases with increased traffic flow. This reduction, however, when measured on a passenger car equivalent basis, decreases with increased traffic flow. The relationships between speed, flow, and traffic composition are based on individual vehicle spot speed data aggregated into 100 five-minute time periods. Attention is given to determining the dynamic structure of these relationships. Two types of dynamic models are developed. The first is a functional model capable of taking a variety of forms to relate average spot speed to present and past values of traffic flow rates and traffic compositions. This model also attemps to account explictly for serial correlation in the regression model disturbances. The second model is based on a distributed lag model in which average spot speed is linearly related to lagged average spot speed, and present and past values of traffic composition. The study methodlogy is detailed and the computed resutls are discussed. It is concluded that there is a need for other studies to broaden the results presented and to incorporate these results into the investment analysis package of planning agencies dealing with rural highways and recreational areas.

Media Info

  • Pagination: p. 539-553
  • Serial:
    • Traffic Quarterly
    • Volume: 33
    • Issue Number: 4
    • Publisher: Eno Transportation Foundation
    • ISSN: 0041-0713

Subject/Index Terms

Filing Info

  • Accession Number: 00312327
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 5 1980 12:00AM