Effects of speed feedback signs and law enforcement on driver speed. (February 2021)

• Record Type: Journal Article
• Authors: Karimpour, Abolfazl; Kluger, Robert; Liu, Chenhui; Wu, Yao-Jan
• Is Part Of: Transportation research. Volume 77(2021)
• Page Start: 55
• Page End: 72
• Publication Date: 2021-02
• Subjects: Driver speed behavior -- Speed feedback sign -- Periodic law enforcement; Automobile drivers -- Psychology -- Periodicals; Automobile driving -- Psychological aspects -- Periodicals; Transportation -- Psychological aspects -- Periodicals; 629.283019
• DOI: 10.1016/j.trf.2020.11.011
• Languages: English
• ISSNs: 1369-8478

Abstract

Highlights: Periodic law enforcement in-tandem with speed feedback sign could modify driver behavior. Speed feedback Sign supported with periodic law enforcement is the most effective strategy. Similar behavior was observed from truck and passenger car approaching speed management strategy. Coordinated efforts between transportation agencies and enforcement will help to address speeding. Abstract: This study analyzes the effects of implementing three speed management strategies, namely speed feedback signs, periodic law enforcement, and speed feedback sign supported with periodic law enforcement on driver speed behavior and compliance. To analyze the effectiveness of each strategy, nine locations in Pima County, Arizona, were studied in a cross-sectional framework. For each study site, the driver's speed, date, time, and vehicle's length were collected at a location prior to the speed management zone as the baseline, at the speed management zone, and downstream of the speed management zone. The general effect showed that all the strategies were effective in reducing average speed and the proportion of drivers exceeding the speed limit. In addition, the results of the robust heteroscedastic ANOVA test showed that among all the strategies, the speed feedback sign supported with periodic law enforcement was the most effective one. Moreover, it was shown that by supporting the speed feedback sign with periodic law enforcement, the reduction in average speed and proportion of drivers exceeding the speed limit would last, even after passing the speed management strategy. In other words, the existence of periodic law enforcement could potentially modify drivers' behaviors and increase the spatial effectiveness of speed feedback signs. Comparing the behavior of truck and passenger car drivers also revealed similar results. That is, both truck and passenger car drivers tend to slow down after observing the speed management strategy. The experimental evidence indicates positive benefits for reducing excessive speeding behaviors at the sites.