ESTIMATING SAFETY EFFECTS OF CROSS-SECTION DESIGN FOR VARIOUS HIGHWAY TYPES USING NEGATIVE BINOMIAL REGRESSION

Improvements in cross-section design are expected to reduce crash rates. Previous studies on the subject have concentrated on two-way, two-lane highways and given less attention to other types of highways. In addition, several of those studies used conventional regression analyses that are not suitable to estimate a discrete non-negative variable like crash frequency. This study uses negative binomial regression analyses to estimate the effects of cross-section design elements on total, fatality, and injury crash rates for various types of rural and urban highways at different traffic levels. The results show that, depending on the highway type investigated, increasing lane width, median width, inside shoulder width, and/or outside shoulder width are effective in reducing crashes. The results also indicate that on four-lane urban highways, the raised median is safer than the two-way left-turn lane median and that the use of an open-graded friction course in lieu of a dense-graded friction course does not have any effect on crash rates.

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/trr/1995/1500/1500-021.pdf
• Record URL:
  • https://scholar.google.com/scholar_lookup?title=ESTIMATING+SAFETY+EFFECTS+OF+CROSS-SECTION+DESIGN+FOR+VARIOUS+HIGHWAY+TYPES+USING+NEGATIVE+BINOMIAL+REGRESSION&author=M.+Hadi&author=J.+Aruldhas&author=L.+Chow&author=J.+Wattleworth&publication_year=1995
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/03611981
• Supplemental Notes:
  • This paper appears in Transportation Research Record No. 1500, Geometric Design, Roadside Safety Features, Roadside Hardware Monitoring, and Scenic Loop Tours. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Authors:
  • Hadi, Mohammed A
  • Aruldhas, Jacob
  • Chow, Lee-Fang
  • Wattleworth, Joseph A
• Publication Date: 1995

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 169-177
• Monograph Title: Geometric design, roadside safety features, roadside hardware monitoring, and scenic loop tours
• Serial:
  • Transportation Research Record
  • Issue Number: 1500
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Binomial distributions; Crash rates; Cross sections; Highway design; Improvements; Medians; Regression analysis; Road shoulders; Rural highways; Traffic lanes; Two way left turn lanes; Urban highways; Width
• Uncontrolled Terms: Lane width; Negative binomial regression analysis
• Old TRIS Terms: Raised pavements
• Subject Areas: Data and Information Technology; Design; Highways; Safety and Human Factors; I20: Design and Planning of Transport Infrastructure; I81: Accident Statistics;

Filing Info

• Accession Number: 00715005
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Dec 26 1995 12:00AM