Exploring the safety in numbers effect for vulnerable road users on a macroscopic scale
Journal article, 2017

A “Safety in Numbers” effect for a certain group of road users is present if the number of crashes increases at a lower rate than the number of road users. The existence of this effect has been invoked to justify investments in multimodal transportation improvements in order to create more sustainable urban transportation systems by encouraging walking, biking, and transit ridership. The goal of this paper is to explore safety in numbers effect for cyclists and pedestrians in areas with different levels of access to multimodal infrastructure. Data from Chicago served to estimate the expected number of crashes on the census tract level by applying Generalized Additive Models (GAM) to capture spatial dependence in crash data. Measures of trip generation, multimodal infrastructure, network connectivity and completeness, and accessibility were used to model travel exposure in terms of activity, number of trips, trip length, travel opportunities, and conflicts. The results show that a safety in numbers effect exists on a macroscopic level for motor vehicles, pedestrians, and bicyclists.

Safety in numbers

Vulnerable road users

Multimodal transportation

Urban context

Author

Ivana Tasic

Chalmers, Civil and Environmental Engineering, Geology and Geotechnics

Rune Elvik

The Institute of Transport Economics (TØI)

Simon Brewer

University of Utah

Accident Analysis and Prevention

0001-4575 (ISSN)

Vol. 109 36-46

Subject Categories

Civil Engineering

DOI

10.1016/j.aap.2017.07.029

More information

Latest update

12/2/2021