ABSTRACT

Application of extreme value theory (EVT) to road safety analysis is gaining interest, thanks to its ability to produce quick and reliable safety evaluations without the use of crash data. Traditionally applied to single collision types and single extreme variables (i.e. surrogate measures of safety), EVT can be further exploited to simultaneously model multiple collision types, with the use of multiple extreme variables. In this paper two bivariate EVT approaches are applied for the safety evaluation of a three-leg unsignalized intersection, considering: (i) two conflict points and a single surrogate measure of safety; (ii) two surrogate measures of safety collected in a single conflict point. Each bivariate analysis was applied with two EVT methods: Component-wise Maxima (CM) and Excesses Over a Threshold (EOT). Bivariate models produced good results, especially with the EOT method, and were able to significantly improve the univariate benchmark results when the two estimation datasets were correlated.

抽象的

由于极值理论（EVT）能够在不使用碰撞数据的情况下进行快速而可靠的安全性评估，因此越来越受到人们的关注。传统上，EVT应用于单个碰撞类型和单个极端变量（即安全性的替代措施），可以通过使用多个极端变量来进一步利用EVT来同时对多个碰撞类型进行建模。本文将两种双变量EVT方法应用于三腿无信号交叉口的安全性评估，考虑到：（i）两个冲突点和单个替代安全性度量；（ii）在单个冲突点中收集的两种替代安全措施。每个双变量分析都应用了两种EVT方法：逐分量最大值（CM）和超出阈值（EOT）。