Abdel-Aty Mohamed, Pande Anurag
Department of Civil & Environmental Engineering, University of Central Florida, Orlando, FL 32816-2450, USA.
J Safety Res. 2007;38(5):581-7. doi: 10.1016/j.jsr.2007.04.007. Epub 2007 Oct 22.
Traffic safety literature has traditionally focused on identification of location profiles where "more crashes are likely to occur" over a period of time. The analysis involves estimation of crash frequency and/or rate (i.e., frequency normalized based on some measure of exposure) with geometric design features (e.g., number of lanes) and traffic characteristics (e.g., Average Annual Daily Traffic [AADT]) of the roadway location. In the recent past, a new category of traffic safety studies has emerged, which attempts to identify locations where a "crash is more likely to occur." The distinction between the two groups of studies is that the latter group of locations would change based on the varying traffic patterns over the course of the day or even within the hour.
Hence, instead of estimation of crash frequency over a period of time, the objective becomes real-time estimation of crash likelihood. The estimation of real-time crash likelihood has a traffic management component as well. It is a proactive extension to the traditional approach of incident detection, which involves analysis of traffic data recorded immediately after the incident. The units of analysis used in these studies are individual crashes rather than counts of crashes.
In this paper, crash data analysis based on the two approaches, collective and at individual crash level, is discussed along with the advantages and shortcomings of the two approaches.
传统上，交通安全文献侧重于识别在一段时间内“更有可能发生更多撞车事故”的位置概况。分析涉及根据道路位置的几何设计特征（如车道数量）和交通特性（如年平均日交通量[AADT]）来估计撞车频率和/或比率（即基于某种暴露量度进行归一化的频率）。最近，出现了一类新的交通安全研究，试图识别“更有可能发生撞车事故”的位置。这两类研究的区别在于，后一类位置会根据一天中甚至一小时内变化的交通模式而改变。
因此，目标不再是估计一段时间内的撞车频率，而是实时估计撞车可能性。实时撞车可能性的估计也有一个交通管理组成部分。它是对传统事件检测方法的一种主动扩展，传统方法涉及对事件发生后立即记录的交通数据进行分析。这些研究中使用的分析单位是单个撞车事故，而不是撞车事故的计数。
本文讨论了基于集体和单个撞车事故层面这两种方法的撞车数据分析，以及这两种方法的优缺点。
