01371393

Component

https://doi.org/10.3141/2280-04

http://scholar.google.com...ayed&publication_year=2012

Recent research has advocated the use of linear intervention models developed within a hierarchical full Bayes context to conduct road safety evaluations. These models acknowledge that the effects of a safety treatment (intervention) do not occur instantaneously but are spread over future time periods. Despite the demonstrated advantages of such models, the manner in which the implemented countermeasures affect safety at the treated locations according to their novelty, direct effects, and indirect effects is not completely understood. A novel nonlinear intervention model was proposed to better understand how safety countermeasures work. To demonstrate the proposed model’s capabilities, linear and nonlinear (Koyck) models were applied to estimate the effectiveness of the installation of shoulder rumble strips on a number of highway segments in the province of British Columbia, Canada. In addition to providing the best fit, the nonlinear Koyck model provided valuable insight into the effectiveness of shoulder rumble strips. This model showed an immediate 24.9% reduction of off-road-right collisions after 1 year that decreased with time and a 19.2% reduction in collisions as a result of permanent treatment. Overall, the findings from this study can have a significant impact on the economic evaluation of safety programs and countermeasures.

01474121

12-0495

English

pp 28–37

2012

Transportation Research Record: Journal of the Transportation Research Board

9780309263214

Print

Appendices; Figures; References

Countermeasures; Highway safety; Mathematical models; Rumble strips

Full Bayes method; Nonlinear analysis

British Columbia

Design; Highways; Safety and Human Factors; I85: Safety Devices used in Transport Infrastructure

TRIS, TRB, ATRI

Feb 8 2012 4:55PM

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