GPS-based Bus Travel Time Distribution And Reliability Analysis Between Adjacent Bus Stations

Bus travel time reliability is one of the important index to evaluate the operating status of the city’s bus system. It can accurately characterize the stability of bus travel time and provide important basis of the evaluation of bus service level for the traveler, transport management and traffic experts. At the same time, the increasing development of mobile detection technology provides a guarantee for the real-time, dynamic, accurate data collection. Based on the analysis of bus GPS data, the report establishes the evaluation method of bus travel time reliability between adjacent bus stations, which provides a new way for the evaluation of bus operating status.First, the report briefly analyses the situation on the GPS and GIS statistics of public transport in three directions, including data structure, data content and data saving. Based on traditional map-matching algorithm, this report improves projection matching algorithm, and uses fast matching method of grid blocks to make the matching of bus GPS data come true. About GPS drift data, the report makes a judgement and helps to eliminate something from them, using matching threshold method. The report also establishes the way on how to deal with fully redundant data. It has been proved that the ways above has good effects, which can be used to calculate the public transport travel timesecondly, the report gives a clear definition of bus travel time between adjacent bus station, and uses4kinds of distribution models, which are Normal Distribution, Log-normal Distribution, Weibull Distribution, Gauss Mixture Distribution, to fit the data in peak-hours and non-peak hours. The results show that the Gauss Mixture Distribution best fits the data and obtain obtain the parameters by Maximum Likelihood estimation.Thirdly, this article puts forward that the travel time reliability index can be divided into three categories:probabilistic evaluation index, deviation evaluation indexes, and evaluation index between the two above. It uses Variation Coefficient and Travel Time Delay Index as evaluation indicators of the bus travel time reliability to establish the evaluation of bus travel time reliability between adjacent bus stations, which is based on Gauss Mixture Distribution.Finally, the report makes quantitative analysis of four factors on the influence of the bus travel time reliability indicators, which includes traffic conditions (bus hour traffic and signal timing plans), road conditions (length between adjacent bus stations and relative location of intersection), weather conditions and bus data sampling interval.The study will provide technical support for bus operation management, information delivery and evaluation of the service level.