Accessibility measure of bus transit networks

A novel gravity-based measure method is proposed for accessibility analysis in transit networks. Trip characteristics of travellers (i.e. waiting time, transfer time, and times of transfer) and spatial distribution of transit stops are usually ignored in the traditional methods; thus, it is necessary and significant to taken them into consideration. The newly proposed method, which utilises service level factors together with transit stop reachability to measure the accessibility, is designed to make up this deficiency. Moreover, the principal component analysis method is innovatively used to determine the weights of service level factors. In order to evaluate the effectiveness of the proposed method, a case study is carried out in the real-world bus transit network in Beijing. Transit accessibility of the network is analysed and some possible reasons for the regions with poor accessibility are summarised. The analysis results are helpful in providing suggestions for policy makers and city planners, which may further improve the service level of bus transit networks. In addition, the concentration of transit accessibility in the selected network is further analysed. With the proposed measure method, the calculated equity results show that Beijing has an equitable bus transit network.