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Title:

Evaluating Safety Effects of Variable Speed Limit System using Empirical Bayesian Before-After Analysis

Accession Number:

01626388

Record Type:

Component

Abstract:

Variable speed limits (VSL) have been increasingly used to improve traffic safety on freeway mainlines. The primary objective of this study was to evaluate the safety impacts of the VSL system implemented on Interstate 5 in Washington since 2010. An observational Empirical Bayesian (EB) before-after analysis was conducted based on 9787 crashes that occurred in the 72-month period. The analysis was conducted for all crashes, and crash severity levels. The EB before-after result implied that the total crash count was reduced by 29% with a standard deviation of 5% after the VSL system was applied in Washington. The counts of crashes with no injury and possible injury decreased more than crashes with severe injuries. The evaluation results of this study are particularly valuable for policy making associated with VSL system implementation projects.

Supplemental Notes:

This paper was sponsored by TRB committee ANB25 Standing Committee on Highway Safety Performance.

Monograph Accession #:

01618707

Report/Paper Numbers:

17-05863

Language:

English

Corporate Authors:

Transportation Research Board

500 Fifth Street, NW
Washington, DC 20001 United States

Authors:

Pu, Ziyuan
Li, Zhibin
Zhu, Wenbo
Cui, Zhiyong

ORCID 0000-0002-5780-4312

Wang, Yinhai

Pagination:

12p

Publication Date:

2017

Conference:

Transportation Research Board 96th Annual Meeting

Location: Washington DC, United States
Date: 2017-1-8 to 2017-1-12
Sponsors: Transportation Research Board

Media Type:

Digital/other

Features:

Figures; Maps; Photos; References (18) ; Tables

Geographic Terms:

Subject Areas:

Highways; Operations and Traffic Management; Safety and Human Factors

Source Data:

Transportation Research Board Annual Meeting 2017 Paper #17-05863

Files:

TRIS, TRB, ATRI

Created Date:

Dec 8 2016 12:21PM