Improving travel time estimation using loop detector data by incorporating ETC data

Michael Do, B-Assignment at Kuwahara Lab, the University of Tokyo, March-June 2009

With the emergence of Advanced Traveler Information Systems (ATIS), it is possible to provide various kinds of information to road users. Travel time is one of the most understood measures for road users. By providing reliable travel time estimates it is possible to influence road users’ route choice and travel behavior, hence improving the performance of traffic networks.

Because of the widespread deployment of loop detectors, most travel time estimation algorithms only have detector data as input. Although detectors continuously collect data, they do not provide an accurate image of the traffic conditions on the road. This is because detectors only collect data at point-locations and not over the entire road.

ETC data on the other hand gives measured travel times over the entire road. But this data arrives too late. By the time travel time is measured, traffic conditions have most likely changed already. By comparing ETC measured travel time with the estimates of the loop detectors, it is possible to evaluate and correct travel time estimations in real-time.