Citation

Shen J, Gu H, Feng X, Yu M, Zheng C. J. Transp. Saf. Secur. 2022; 14(9): 1531-1551.

Copyright

(Copyright © 2022, Southeastern Transportation Center, and Beijing Jiaotong University, Publisher Informa - Taylor and Francis Group)

DOI

10.1080/19439962.2021.1941460

PMID

unavailable

Abstract

A bus-involved crash unavoidably affects many passengers, causing severe consequences. Nonetheless, few studies have been comprehensively conducted to analyze the bus-crash severity. Accordingly, using the data of the bus crashes that have occurred in the UK in 2017-2019, this study constructs an extended hierarchical ordered probit model with heteroscedasticity (HHOPIT) to investigate the factors influencing bus-crash severity levels. Using AIC and BIC indicators, we confirm that considering the impact of variable heterogeneity on the threshold and error term is essential for interpreting bus-crash severity. Particularly, the frontal-impact-crash, wet-road, and moderate-speed-limit variables produce heteroscedasticity and significantly affect the crash severity level. Additionally, overturned-crash, multi-vehicle-crash, and morning-crash variables induce threshold variability. Based on the marginal effect of variables, it is confirmed that road-section, frontal-impact-crash, wet-road, junction-exit, and main-way variables increase the likelihood of severe injuries. Furthermore, the probability of slight injuries as consequences, increases with the influence of lower-speed-limit, roundabout, urban-crash, parking-crash, and moderate-speed-limit variables. This study additionally determines the factors that have inconsistent effects on the consequence of bus and passenger-car crashes. To improve the safety of bus services, the authorities must carefully consider the heterogeneity and specificities of the factors affecting bus-crash severity and appropriately formulate targeted policies.

Language: en

Keywords

bus-involved crashes; Crash severity; heteroscedasticity; hierarchical ordered probit model