1. Assessment of drivers’ comprehension of traffic signs based on their traffic, personal and social characteristics Author: Hashim AI-Madani, Abdul-Rahman Al-Janahi Transportation Research Part F (2002) 63-76 Speaker: Yang Kun, Ou

2. Introduction The relationship between drivers’ personal characteristics and their comprehension of posted signs is investigated in this study

3. Introduction The characteristics considered here include: –experience –accident per experience ratio –age –marital status –sex type –nationality –educational background –monthly income

4. Purpose The drivers’ personal characteristics are primarily associated with their understanding capabilities and with their accident involvement rates

5. Reference Some others considered drivers’ response time and speed of comprehension of the meaning of the sign (Ells & Dewar, 1979) as well as the legibility distance (Halpern, 1984; Pignataro, 1973) Jainski (1977) and Chapanis (1994) tested the effect of sign colours on driver’s perception

6. Method The questionnaire involved short-answer and multiple-choice questions The short-answer questions were designed to identify drivers’ characteristics and the multiple-choice questions evaluated drivers’ comprehension of posted traffic signs

7. Method The stratification was proportioned based on their occupations. Occupation was stratified according to the following twelve categories: –(a) economic and finance –(b) private business –(c) education –(d) students –(e) judiciary and security –(f) information and tourism –(g) health –(h) social and agriculture –(i) industry and electric –(j) transportation and communication, –(k) unemployed –(l) other sectors

8. Sample multiple-choice questions

9. Overall analysis The score was tested against driver’s characteristics using a multivariate approach The parameters used can be divided into the following terms: A linear term; considering drivers’ age (A), years of education (E), monthly income (I) and years of driving experience (X).

10. Overall analysis A quadratic term; considering the squares of A, E and I minus the corresponding average of each, i.e. (A-average AT) 2, (E-average ET) 2 and (I-average IT) 2 The standard error of each variable will also be presented to indicate the influence of each independent variable on drivers’ understanding of signs

11. Overall analysis ACDPREXP (Driver’s accident involvement+ 1)/Years of driving experience Post-hoc tests for analysis of variance were based on least significant difference (LSD) and Boneferroni tests

12. Results Drivers’ mean age in the UAE followed by Qatar is greater than that in other states These are as follows (in US Dollars): 16,894, 13,572, 12,833, 5696 and 7163(UAE,Kuwait, Qatar, Oman and Bahrain)

13. Results knowledge of posted signs in these states varied between 50% and 62% American and European drivers are better than other nationalities

14. Results

16. Nationality and experience –Drivers of other nationalities with over 10 years of experience comprehend significantly better than less experienced drivers

17. Results

18. Education, income and age –Drivers’ monthly income and years of education were significantly related to their understanding of posted signs –Education and income are usually correlated –It does not improve significantly with experience for drivers with higher level of education.

19. Results

20. Age by experience –drivers representing eldest and most experienced ones should be the most knowledgeable in traffic sign recognition and youngest and least experienced should be the least knowledgeable –drivers in the younger age groups (those below 35 years) in the various experience groups (Table 6) understand the signs significantly less well than those in the older groups (35–44 and 45–55 years)

21. Results

22. Sex type and marital status –While male drivers have a significant better comprehension of signs than females (Table 2), marital status has no effect –The average understanding of posted signs for male, female, married and single drivers considering the western drivers alone are as follows: 73%, 67%, 73% and 69%, respectively –Female drivers’ comprehension of signs proved not to be improving significantly with years of driving experience

23. Results

24. Marital status by experience –Although married drivers hold greater social and economic responsibilities than single drivers, marital status was not related with better understanding of signs

25. Results

26. Conclusions The drivers were able to correctly identify only 50–60% of the signs drivers’ years of education, gender, monthly income and nationality have significant effect on their understanding of traffic signs Western drivers comprehend the signs significantly better than drivers of other nationalities

27. Conclusions Young, holding low educational qualifications and in low income categories comprehend signs significantly less well than those who are in the middle age or older, holding high level of education and with high income Male drivers with over ten years of driving experience are significantly better than less experienced male drivers.