Use of Disruptive Technologies to Support Safety Analysis and Meet New Federal Requirements

States are required to have access to annual average daily traffic (AADT) for all public paved roads, including non-federal aid system (NFAS) roadways. The expectation is to use AADT estimates in data-driven safety analysis. Because collecting data on NFAS roads is financially difficult, agencies are interested in exploring affordable ways to estimate AADT. The goal of this project was to determine the accuracy of AADT estimates developed from alternative data sources and quantify the impact of AADT on safety analysis. The researchers compared 2017 AADT data provided by the Texas and Virginia Departments of Transportation against probe-based AADT estimates supplied by StreetLight Data Inc. Further, the research team developed safety performance functions (SPFs) for Texas and Virginia and performed a sensitivity analysis to determine the effects of AADT on the results obtained from the empirical Bayes method that uses SPFs. The results showed that the errors stemming from the probe AADT estimates were lower than those reported in a similar study that used 2015 AADT estimates. The sensitivity analysis revealed that the impact of AADT on safety analysis mainly depends on the size of the network, the AADT coefficients, and the overdispersion parameter of the SPFs.

• Record URL:
  https://safed.vtti.vt.edu/wp-content/uploads/2021/04/Final-Version-04-113-Use-of-Disruptive-Technologies-to-Support-Safety-Analysis-and-Meet-New-Federal-Requirements.pdf
• Supplemental Notes:
  • This document was sponsored by the U.S. Department of Transportation, University Transportation Centers Program.
• Corporate Authors:

  Safety Through Disruption University Transportation Center (Safe-D)

  Texas A&M Transportation Institute
  College Station, TX  United States 

  Virginia Polytechnic Institute and State University, Blacksburg

  Virginia Tech Transportation Institute
  3500 Transportation Research Plaza
  Blacksburg, VA  United States  24061

  Office of the Assistant Secretary for Research and Technology

  University Transportation Centers Program
  Department of Transportation
  Washington, DC  United States  20590
• Authors:
  • Tsapakis, Ioannis
  • 0000-0003-4529-4949
  • Das, Subasish
  • 0000-0002-1671-2753
  • Khodadadi, Ali
  • 0000-0002-3413-8687
  • Lord, Dominique
  • 0000-0002-7434-6886
  • Morris, Jessica
  • 0000-0002-7309-4701
  • Li, Eric
  • 0000-0001-8210-8215
• Publication Date: 2020-3

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Appendices; Figures; References; Tables;
• Pagination: 37p

Subject/Index Terms

• TRT Terms: Accuracy; Annual average daily traffic; Data analysis; Data collection; Estimating; Impacts; Probe vehicles; Safety analysis; Sensitivity analysis
• Identifier Terms: Safety Performance Functions; Texas Department of Transportation; Virginia Department of Transportation
• Subject Areas: Data and Information Technology; Highways; Safety and Human Factors;

Filing Info

• Accession Number: 01771766
• Record Type: Publication
• Report/Paper Numbers: 04-113
• Contract Numbers: 69A3551747115/04-113
• Files: UTC, TRIS, ATRI, USDOT
• Created Date: May 21 2021 10:54AM