Imperial College London
Portrait Picture

Professor Dan Graham

Faculty of Engineering, Department of Civil and Environmental Engineering

Professor of Statistical Modelling
 
 
 
//

Contact

 

+44 (0)20 7594 6088d.j.graham Website

 
 
//

Assistant

 

Ms Maya Mistry +44 (0)20 7594 6100

 
//

Location

 

611Skempton BuildingSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Li:2016:10.1016/j.aap.2016.09.007,
author = {Li, H and Graham, DJ},
doi = {10.1016/j.aap.2016.09.007},
journal = {Accident Analysis & Prevention},
pages = {153--161},
title = {The Heterogeneous Treatment Effects of Speed Cameras on Road Safety},
url = {http://dx.doi.org/10.1016/j.aap.2016.09.007},
volume = {97},
year = {2016}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - This paper analyses how the effects of fixed speed cameras on road casualties vary across sites with different characteristics and evaluates the criteria for selecting camera sites. A total of 771 camera sites and 4787 potential control sites are observed for a period of 9 years across England. Site characteristics such as road class, crash history and site length are combined into a single index, referred to as a propensity score. We first estimate the average effect at each camera site using propensity score matching. The effects are then estimated as a function of propensity scores using local polynomial regression. The results show that the reduction in personal injury collisions ranges from 10% to 40% whilst the average effect is 25.9%, indicating that the effects of speed cameras are not uniform across camera sites and are dependent on site characteristics, as measured by propensity scores. We further evaluate the criteria for selecting camera sites in the UK by comparing the effects at camera sites meeting and not meeting the criteria. The results show that camera sites which meet the criteria perform better in reducing casualties, implying the current site selection criteria are rational.
AU  - Li,H
AU  - Graham,DJ
DO  - 10.1016/j.aap.2016.09.007
EP  - 161
PY  - 2016///
SN  - 0001-4575
SP  - 153
TI  - The Heterogeneous Treatment Effects of Speed Cameras on Road Safety
T2  - Accident Analysis & Prevention
UR  - http://dx.doi.org/10.1016/j.aap.2016.09.007
UR  - http://hdl.handle.net/10044/1/40210
VL  - 97
ER  -
Download