Using fuzzy clustering of user perception to determine the number of level-of-service categories for bus rapid transit

Abstract

The concept of level of service (LOS) is meant to reflect user perception of the quality of service provided by a transportation facility or service. Although the LOS of bus rapid transit (BRT) has received considerable attention, the number of levels of service of BRT that a user can perceive still remains unclear. Therefore, this paper addresses this issue using fuzzy clustering of user perception. User perception is a six-dimension vector including perceived arrival time, perceived waiting time, bus speed perception, passenger load perception, perceived departure time, and overall perception. The research team developed a smartphone-based transit travel survey system to conduct the user perception surveys in three BRT systems in China. Fuzzy C-means clustering, improved using a simulated annealing genetic algorithm, was adopted to partition user perception into 2 to 10 clusters. Seven cluster validity indices were used to determine the appropriate number of LOS categories. The results indicate that users can perceive two to four levels of service.