Real-time bus arrival information system-an empirical evaluation

Waiting time uncertainty is one of the main determinants of public transport reliability and overall level-of-service. The dissemination of real-time information concerning vehicle arrivals is often considered an important measure to reduce unreliability. Moreover, the prediction of downstream vehicle trajectories could also benefit real-time control strategies. In order to adequately analyze the performance of real-time bus arrival information system, the generated predictions have to be compared against empirical bus arrival data. A conventional real-world bus arrival prediction scheme is formulated and applied on the trunk lines network in Stockholm. This scheme was found to systematically underestimate the remaining waiting time by 6.2% on average. Prediction error accuracy and reliability varies considerably over time periods, along the route and as a function of the prognosis horizon. The difference between passengers´ waiting time expectations derived from the timetable and real-time information is equivalent to 30% of the average waiting time.