Determinants of route choice and value of traveler information: A field experiment

Drivers receive value from traveler information in several ways, including the ability to save time, but perhaps more important is the value of certainty as it affects other personal, social, safety, or psychological factors. This information can be economically valued. The benefit of reduction in driver uncertainty when information is provided at the beginning of the trip is the main variable measured in this research. User preferences for routes were assessed as a function of the presence and accuracy of information while controlling for other trip and route attributes. Data were collected in a field experiment in which 113 drivers, given real-time travel time information with varying degrees of accuracy, drove four alternative routes between a preselected origin-destination pair in the Twin Cities, Minnesota, metropolitan area. Ordinary regression, multinomial, and rank-ordered logit models produced estimates of the value of information with some variation. Results showed that travelers were willing to pay up to $1 per trip for pretrip travel-time information. The value of information is higher for commute and event trips and when congestion on the usual route is heavier. The accuracy of the traveler information was also a crucial factor. Travelers will not pay for information unless they perceive it to be accurate. Most travelers (70%) prefer that such information be provided free by the public sector, whereas some (19%) believe that it is better for the private sector to provide such service at a charge. REFERENCES93-99 Distributed Controller Design Approach to Dynamic Speed Limit Control Against Shockwaves on Freeways A. Popov, A. Hegyi, R. Babus?ka, and H. Werner A. Popov and H. Werner, Institute of Control Systems, Hamburg University of Technology, Eissendorferstrasse 40, 21073 Hamburg, Germany. A. Hegyi, Transport and Planning, Delft University of Technology, P.O. Box 5048, 2600 GA Delft, Netherlands. R. Babus? ka, Delft Center for Systems and Control, Delft University of Technology, Mekelweg 2, 2628 CD Delft, Netherlands. Corresponding author: A. Hegyi, a.hegyi@tudelft.nl. DOI: 10.3141/2086-11 Dynamic speed limits can be used to eliminate shockwaves on freeways. Shockwaves are typically short traffic jams that emerge at bottlenecks and travel in the upstream direction on the freeway. These shockwaves lead to increased travel times and possibly to unsafe situations. A speed limit control approach to resolving shockwaves was developed based on a distributed controller design technique. The controller is distributed in the sense that each speed limit sign has its own controller. The controller parameters are optimized by numerical optimization, assuming that the controller structure and parameters are the same for each controller. The resulting performances are compared for several designs, differing in the controller order and the extent that the upstream and downstream traffic states are used as inputs for the controller. Other controllers known from the literature are based on switching schemes using local information only or are centralized model-based controllers with high computational loads. The proposed method gives a systematic way to design distributed controllers using the appropriate amount of upstream and downstream traffic information. The resulting controllers are attractive from the implementation point of view because they are very efficient. They do not require extensive online computations and use only information from the neighborhood. For the design scenario used, the controller successfully resolved the shockwave and reduced the total time spent by approximately 20% compared with the uncontrolled case, which is comparable to the performance of the best controllers known from the literature.