Analysis of Route Choice Behavior and Consciousness for Travel Time Information on Expressway

This paper reports on a study that analyzed route choice behavior and understanding of travel time information provided on the expressway. Travel time information effects drivers’ route choice behavior, and is regarded as one of the effective measures to ease traffic congestion. In this study, the authors administered a questionnaire survey on travel time information. The survey was conducted at Service Areas (SA) and Parking Areas (PA) on the expressways in Japan. The questionnaire mainly consisted of questions on the consciousness and needs for travel time information and their route choice behavior with/without the information. Approximately 34% of the drivers in vehicles without car navigation systems use the highway's travel time information board for an estimation of the travel time to their exit. The results showed that approximately 80% of drivers accept plus-or-minus 10 minutes error of travel times. When an increase or a decrease arrow was added to travel time information under the questionnaire, it had a considerable influence on their route choice behavior. The authors conclude that the display of the arrow on travel time information had the potential to relieve traffic congestion effectively.