Modeling Violation Behavior at Highway-Rail Grade Crossings Using a Driver Anxiety Surrogate Measure

Abstract

When responding to changes in the status of traffic controls, drivers may experience uncertainties caused by incomplete and inaccurate information. These uncertainties may result in driver anxiety during the decision-making process and lead to poor decisions. It is hypothesized that a better understanding of the decision-making process, and the associated gate violation behavior at highway-rail grade crossings (HRGCs), will lead to effective gate violation countermeasures and, ultimately, safer HRGCs. This paper examines the relationship between driver anxiety and the characteristics of inappropriate decisions that result in gate violations. Field data were collected at a gated HRGC test bed in Lincoln, Nebraska. A total of 372 vehicles were studied which included 116 first-to-stop and 256 last-to-proceed vehicles, with 76 proceeding vehicles identified as gate violations. A fuzzy-based, degree of anxiety metric is adopted as a surrogate measure of driver anxiety in the decision-making process. The results show that HRGC gate violations were linearly related to the anxiety metric values. In other words, all things being equal, as the anxiety value of the metric increased so did the probability of a violation. The maximum anxiety was felt when drivers were approximately 5 s from the stop line at the onset of the HRGC’s flashing lights. The results provide guidance for applying ancillary or advanced technologies for increasing HRGC safety, such as where to install a roadside prepare-to-stop system, or when to issue an in-vehicle warning in the context of automated driving systems.