Effects of intersection collision warning systems on drivers’ reaction time: a hazard-based duration model

The objective of this study was to examine the effect ICWSs on drivers’ behavior, in response to a potential conflict event at the intersections; in this case, a violator vehicle from right and left that failed to stop represented the potential conflict. The ICWSs were audio warning message and visual warning. Both the audio warning message and the visual warning provided to the driver the direction of the violator vehicle. Drivers’ reaction times were modeled following the survival analysis, by the use of the accelerated failure time (AFT) duration model with a Weibull distribution. The applied model identified one significant variable influencing the reaction time (Vi driver’s initial speed value) and the warning signal condition; the direction of the violator vehicle did not affect significantly the reaction time of drivers. For the condition of audio message warning and visual warning, the reaction time was 43.1 % and 34.5% shorter than that for the baseline condition, respectively. In addition, the drivers’ reaction time for the audio message warning was 22% shorter than that for the visual warning (statistically significant).