This study addresses the issue of whether the message content of variable message signs (VMS) can be used as a control variable to favorably influence traffic conditions in real-time. The focus is on the level of detail of information displayed on the VMS, and not human factor issues. It implies an understanding of driver sensitivity to information content. Also, for real-time implementation, the displayed information should be consistent, timely, and reliable. A framework is developed for optimizing system performance under incidents using the VMS message content as the primary control parameter. It consists of: (i) an efficient control strategy to enhance system performance using the VMS and information on current traffic conditions received from on-line sensors; (ii) a driver response model to supplied information that addresses the effect of the message content on drivers' en-route switching decisions; and (iii) an incident clearance time prediction model which predicts the expected delay due to an incident.

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variable message signs, real-time incident management, advanced traffic management systems, simulation-based optimization, consistent route diversion models, internet-based driver survey, incident clearance time prediction model, SPR-2208

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Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, IN

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