Fuzzy Logic-Based User Perceptions of Signalized Intersection Level of Service

Delay has been selected as the only measure for determining signalized intersection level-of-service (LOS). Previous studies, mostly for freeways, reported that road users consider multiple factors in their evaluation of LOS, including traffic-related and non-traffic factors. The findings from more than 1,300 responses to a web-based stated-preference survey suggest that road users consider multiple factors for the evaluation of signalized intersections, including left-turn treatment and pavement markings. A methodology based on fuzzy logic is presented in this paper to determine signalized intersection LOS that explicitly accounts for user perceptions. To reflect the fuzziness of user perceptions, rigid LOS thresholds were replaced with fuzzy numbers to make it more consistent with driver perceptions. Fuzzy inferences, which were based on a set of fuzzy rules, were applied to combine important factors at signalized intersections for deriving a composite LOS measure. Membership grades were used to assign confidence levels for each LOS category. A case study with different improvement scenarios was conducted to illustrate the proposed method. Overall, the fuzzy logic method simulates the human reasoning process and provides an alternative to quantify user perceptions of signalized intersection LOS.


  • English

Media Info

  • Media Type: CD-ROM
  • Features: Figures; References; Tables;
  • Pagination: 28p
  • Monograph Title: TRB 86th Annual Meeting Compendium of Papers CD-ROM

Subject/Index Terms

Filing Info

  • Accession Number: 01049519
  • Record Type: Publication
  • Report/Paper Numbers: 07-1111
  • Files: TRIS, TRB
  • Created Date: Feb 8 2007 5:43PM