Human Factors in the Fundamental Diagram

Some observations are made on the fundamental diagram of freeway traffic, among which are three influence regions, three types of transition around capacity, and capacity drop phenomenon. This research aspires to interpret these observations from a human factors perspective in traffic flow theory. Of particular interest are the following human factors: drivers’ choice of desired speeds, perceived effective vehicle lengths, perception–reaction times, and aggressiveness. It appears that all four factors are involved in characterizing traffic flow, though they play different roles in the fundamental diagram. Different combinations of these factors give rise to the above-mentioned influence regions, transition around capacity, and capacity drop. Of critical importance in determining the transition around capacity and capacity drop is drivers’ aggressiveness, a factor that has long been overlooked in the past. This paper provides a detailed account of where it comes from and how it influences the fundamental diagram.


  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References; Tables;
  • Pagination: pp 30-45
  • Monograph Title: Celebrating 50 Years of Traffic Flow Theory: A Symposium. August 11-13, 2014, Portland, Oregon
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01604732
  • Record Type: Publication
  • Files: TRIS, TRB, ATRI
  • Created Date: Jun 20 2016 2:48PM