Examining the characteristics between time and distance gaps of secondary crashes  

作　　者：Xinyuan Liu Jinjun Tang Chen Yuan Fan Gao Xizhi Ding 

机构地区：[1]Smart Transport Key Laboratory of Hunan Province,School of Transport and Transportation Engineering,Central South University,Changsha 410075,China [2]Department of Computer Science,City University of Hong Kong,999077,Kowloon Tong,Hong Kong,China [3]Department of Geography and Resource Management,The Chinese University of Hong Kong,Shatin,NT 999077,Hong Kong,China

出　　处：《Transportation Safety and Environment》2024年第1期116-131,共16页交通安全与环境（英文）

基　　金：This research was funded in part by Innovation-Driven Project of Central South University(Grant No.2020CX041);the Fundamental Research Funds for the Central Universities of Central South University(Grant No.2022ZZTS0717)。

摘　　要：Understanding the characteristics of time and distance gaps between the primary(PC)and secondary crashes(SC)is crucial for preventing SC ccurrences and improving road safety.Although previous studies have tried to analyse the variation of gaps,there is limited evidence in quantifying the relationships between different gaps and various influential factors.This study proposed a two-layer stacking framework to discuss the time and distance gaps.Specifically,the framework took random forests(RF),gradient boosting decision tree(GBDT)and eXtreme gradient boosting as the base classifiers in the first layer and applied logistic regression(LR)as a combiner in the second layer.On this basis,the local interpretable model-agnostic explanations(LIME)technology was used to interpret the output of the stacking model from both local and global perspectives.Through SC dentification and feature selection,346 SCs and 22 crash-related factors were collected from California interstate freeways.The results showed that the stacking model outperformed base models evaluated by accuracy,precision,and recall indicators.The explanations based on LIME suggest that collision type,distance,speed and volume are the critical features that affect the time and distance gaps.Higher volume can prolong queue length and increase the distance gap from the SCs to PCs.And collision types,peak periods,workday,truck involved and tow away likely induce a long-distance gap.Conversely,there is a shorter distance gap when secondary roads run in the same direction and are close to the primary roads.Lower speed is a significant factor resulting in a long-time gap,while the higher speed is correlated with a short-time gap.These results are expected to provide insights into how contributory features affect the time and distance gaps and help decision-makers develop accurate decisions to prevent SCs.

关 键 词：secondary crash(SC) time and distance gaps stacking framework local interpretable model-agnostic explanations(LIME) 

分 类 号：U491.31[交通运输工程—交通运输规划与管理]