Open AccessComparative study for safety performance measures of signalized intersection sites
Author(s) -
Raghad Zeki Abdul Majeed,
Hussein A. Ewadh
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/737/1/012123
Subject(s) - crash , intersection (aeronautics) , bayes' theorem , statistics , identification (biology) , computer science , transport engineering , hazard , mathematics , engineering , bayesian probability , botany , biology , programming language , chemistry , organic chemistry
The decision on which safety performance measure to use for diagnosis of sites with probable to profit from safety improvements is a major factor in making the right decision for the guidance of resources. This study concentrated on introducing a quantitative comparison of sites according to four crash-based methods suggested in the Highway Safety Manual (HSM). Archived crash data for three years are obtained to conduct a comparison course. As a case study, the analysis and measure of safety for 9 four-leg signalized intersections in Baghdad city have been done independently using Empirical Bayes method (EB-method), observed Crash Frequency (CF), Crash Rate (CR) and Empirical Bayes Adjustment (EB-adj.) as safety performance measures in HSM. In this paper the EB-method is used as a benchmark for comparison. The safety measures are evaluated through rank correlation analysis while hazard location identification results are compared through the use of values rank-based mean absolute error. Quantitative evaluation tests showed that each of EB-adj and observed CF correlated well with EB-method while CR method exhibited poor performance in comparison with EB-method and was the worst in hazard location identification. This result is quite confusing since many agencies still depend on the CR method in traffic safety analyses.