Motorist Response to Arterial Variable Message Signs

Abstract

Although much research into driver attitudes toward and responses to expressway-based variable message signs (VMSs) has been conducted, little research has explored motorist responses to VMSs on arterial surface streets. Arterial VMSs, located near main expressway entrance points, may prove to be more effective at inducing motorists to divert during congestion or incidents than their highway counterparts because they will allow drivers to have many more routing options before they commit to the expressway system. The results of a study conducted in Milwaukee, Wisconsin, to discern motorist attitudes toward arterial VMSs and the diversion behaviors induced by those signs are presented. A revealed-preference survey conducted in the immediate vicinity of the arterial VMS found that nearly two-thirds of the respondents obtained traffic information from the signs more than once per week. Furthermore, 66% of those surveyed changed their route at least once per month because of the information received from the arterial VMS. These results demonstrate that motorists are responsive to messages on arterial VMSs; arterial VMSs have an important impact on motorist’s travel behavior and are thus a key component in a comprehensive traffic management system. More specifically, an ordered logit model revealed that the propensity to divert was correlated to the frequency that a driver encounters an arterial VMS, motorists’ perception of the VMS information as useful, and motorists’ trust in the accuracy of the VMS information. The reasons for this diversion response are primarily to save travel time and to avoid expressway incidents.