Study on impact of taxi status to probe car system performance

Link travel time is used to represent the jam level of road. Probe car system calculates link travel time based on taxi GPS data. Basically, a taxi has two statuses: heavy taxi (with passenger) and light taxi (without passenger). By analyzing taxi GPS data and link travel time, generally, we found average link travel time generated by heavy taxi is shorter than that generated by light taxi on the same link. In this paper, the reason is analyzed and a method is presented to amend the link travel time generated by light taxi GPS data. Series of experiments of probe car system were carried out in Beijing of China recently. The performance of probe car system was evaluated in the experiments. The result shows the accuracy of link travel time could be increased if light taxi data was particularly processed.