Travelers’ Potential Demand toward Flex-Route Transit: Nanjing, China, Case Study

As an innovative combination of conventional fixed-route transit and demand-responsive services, flex-route transit is a promising transit option that can address the travel needs of residents in growing low-density suburban and rural areas. This paper assesses potential demand and passengers’ service design preferences prior to the deployment of a flex-route transit service in China. Using the city of Nanjing as an example, a survey was designed and implemented that involves a series of stated-preference experiments in order to (1) examine travelers’ willingness to use flex-route transit services, (2) identify the most promising users, and (3) guide the service design and policymaking before actual operation. Three discrete choice models, namely multinomial logit model, nested logit model, and panel mixed logit model, are applied to describe the mode-choice process using the data collected from the survey. An orthogonal design is used to generate the stated-choice experiments among traditional fixed-route transit, private cars, and hypothetical flex-route transit. Walking time, waiting time, in-vehicle time, and cost are selected as alternative attributes, which vary across each choice scenario. The survey results show that nearly 78% of respondents are willing to try the flex-route transit service. Women, bike-share members, and people who are disabled, retired, or need to transfer to the metro are the target groups of the flex-route transit service. The choice model results also indicate that slack time between checkpoints and vehicle delays should be kept within a reasonable range when designing and operating flex-route transit services.