A Dynamic Holding Method to Avoid Bus Bunching on High-Frequency Transit Routes: From Theory to Practice August 2012 – June 2017 Dissertation Research Project
I have developed a new dispatching method to stabilize headways and stop bus bunching. The method uses real-time vehicle information to replace schedules on high-frequency transit routes. In a series of simulation experiments, I found that the proposed holding method dispatched transit vehicles with more stable headways and used less holding time than other methods used in practice and recommended in the literature. I established research partnerships with transit agencies and successfully implemented the holding method on the Atlanta Streetcar, the VIA Bus Rapid Transit Primo Route in San Antonio, TX, and the Georgia Tech Red Stinger Route. I developed an open- source platform to compute holding times and trained operators to receive holding instructions from the software instead of their regular schedule. The method helped reduce bus bunching and passenger waiting time; it is currently being considered for permanent implementation.
• Berrebi, S. J., Watkins, K. E., & Laval, J. A. (2015). A real-time bus dispatching policy to minimize passenger wait on a high frequency route. Transportation Research Part B: Methodological.
• Berrebi, S. J., Hans, E., Chiabaut, N., Laval, J. A., Leclercq, L., & Watkins, K. E. (2017). Comparing bus holding methods with and without real-time predictions. Transportation Research Part C: Emerging Technologies.
• Berrebi, S. J., Crudden, O., S., & Watkins, K. E. (2018). Translating research to practice: Implementing real-time control on high-frequency transit routes. Transportation Research Part A: Policy and Practice.
Minutes Matter: A Guide to Bus Transit Service Reliability, Transit Cooperative Research Program Report A-42
The TCRP Report A-42 is a guide for transit agencies to diagnose and manage bus transit service reliability. Based on the literature and on a survey of 150 transit agencies, I have drafted a report on factors of unreliability and possible treatments. I categorized factors of reliability by type and discussed their effect on customer experience and operations. I reported on cost and effectiveness of available treatments to address causes of reliability. The report will be published in September 2018.