Bluetooth Sensor Data and Ground Truth Testing of Reported Travel Times

Travel time information is a valuable statistic in transportation systems. This information supports a wide body of decision makers, from passengers seeking to minimize trip times to authorities who rely on these data for monitoring and planning purposes as well as for emergency responses. Collecting accurate travel time information is a pivotal task. In recent years, the I-95 Corridor Coalition has provided extensive real-time travel information for several freeway segments and arterials surrounding I-95 on the East Coast under the Coalition's Vehicle Probe Project. As a partner to this collaborative effort, the University of Maryland has been responsible for data verification and validation. This process involves comparing reported speeds with observations recorded by Bluetooth sensors to evaluate the accuracy of the reported data. This paper discusses the comparison method specified in the project documentation and explores some alternative approaches and their merits and limitations.