Newswise — With the surge in motorcycle registrations, motorcycle crashes have become a pressing challenge, especially in developing countries. Cambodia, where motorcycles serve as the primary mode of transportation, faces an acute issue of high mortality rates from such crashes. In traditional crash analysis, injury severity and crash size are often studied independently. However, both observed and unobserved factors may simultaneously affect these two indicators, implying a potential interrelationship. Neglecting this joint occurrence can lead to biased parameter estimation. Yet, research on the interdependence between injury severity and crash size in motorcycle crashes remains scarce.
Therefore, Yaqiu LI, Lon VIRAKVICHETRA, Junyi ZHANG, Haoran LI, and Yunpeng LU from institutions including Southeast University, Hiroshima University, Wuhan University of Science and Technology, and Tsinghua University Suzhou Automotive Research Institute have jointly conducted a research entitled “Jointly modeling the dependence of injury severity and crash size involved in motorcycle crashes in Cambodia using a copula-based approach”.
This study aims to fill the existing research gap by simultaneously analyzing the factors influencing both injury severity and motorcycle crash size, with a particular focus on their interdependence using a copula-based approach. Six copula-based models were developed with the ordered logit model to capture the ordinal nature of injury severity and crash size. By analyzing 2016 motorcycle crash data from Cambodia, the Frank copula framework was identified as the most effective among the six approaches. The findings revealed that factors such as motorcycle-to-pedestrian collisions, head-on collisions, X junctions, and national roads significantly increase both motorcyclist injury severity and crash size. Additionally, human factors, temporal factors , and other road factors also exert notable impacts on either injury severity or crash size. These insights hold great value for policymakers to formulate targeted strategies for enhancing motorcycle safety within transportation systems.
The paper “Jointly modeling the dependence of injury severity and crash size involved in motorcycle crashes in Cambodia using a copula-based approach” authored by Yaqiu LI, Lon VIRAKVICHETRA, Junyi ZHANG, Haoran LI, Yunpeng LU. Full text of the paper: https://doi.org/10.1007/s42524-024-0302-8.
