title: Quantifying the impact of adaptive traffic control systems on crash frequency and severity: Evidence from Oakland County, Michigan.
abstract: Despite seeing widespread usage worldwide, adaptive traffic control systems have experienced relatively little use in the United States. Of the systems used, the Sydney Coordinated Adaptive Traffic System (SCATS) is the most popular in America. Safety benefits of these systems are not as well understood nor as commonly documented.
  
  
  
  This study investigates the safety benefits of adaptive traffic control systems by using the large SCATS-based system in Oakland County, MI known as FAST-TRAC. This study uses data from FAST-TRAC-controlled intersections in Oakland County and compares a wide variety of geometric, traffic, and crash characteristics to similar intersections in metropolitan areas elsewhere in Michigan. Data from 498 signalized intersections are used to conduct a cross-sectional analysis. Negative binomial models are used to estimate models for three dependent crash variables. Multinomial logit models are used to estimate an injury severity model. A variable tracking the presence of FAST-TRAC controllers at intersections is used in all models to determine if a SCATS-based system has an impact on crash occurrences or crash severity.
  
  
  
  Estimates show that the presence of SCATS-based controllers at intersections is likely to reduce angle crashes by up to 19.3%. Severity results show a statistically significant increase in non-serious injuries, but not a significant reduction in incapacitating injuries or fatal accidents.
authors.affiliation: AECOM, 27777 Franklin Road, Suite 2000, Southfield, MI, 48034, USA. Electronic address: j4fink@gmail.com.
authors.forename: Joshua
authors.initials: J
authors.lastname: Fink
authors.affiliation: Civil and Construction Engineering, Western Michigan University, 1903 W. Michigan Avenue, Kalamazoo, MI 49008-5316, USA. Electronic address: valerian.kwigizile@wmich.edu.
authors.forename: Valerian
authors.initials: V
authors.lastname: Kwigizile
authors.affiliation: Civil and Construction Engineering, Western Michigan University, 1903 W. Michigan Avenue, Kalamazoo, MI 49008-5316, USA. Electronic address: jun.oh@wmich.edu.
authors.forename: Jun-Seok
authors.initials: JS
authors.lastname: Oh
mesh_terms: D000063:Accidents, Traffic / Q000517:prevention & control*; D003430:Cross-Sectional Studies; D004779:Environment Design / Q000592:standards; D006801:Humans; D016015:Logistic Models; D008824:Michigan; D015233:Models, Statistical; D012449:Safety / Q000592:standards
keywords: Adaptive traffic control; Crash frequency; Crash severity; Traffic safety