Benefits and harms of DRT in suburban areas – analysis of user motivations, ridership, and side effects of an app-based demand-responsive transit

Since the rebirth of demand-responsive transit (DRT) after 2010 many failed and discontinued initiatives have been observed. The issues range from inadequate technology, ill-defined spatial and temporal conditions, to missing knowledge of user preferences, low ridership, and of course funding, since many trials are ceased once the subsidy is stopped. In this paper, we explore the use and effects of an app-based DRT in a suburban environment based on the data collected from users and non-users of a newly launched service in Austria. The results indicate that the service performs well as a feeder mode for rail transportation with positive user reviews. However, there are concerns about a limited operating area, too short operating hours and low pooling effects (occupancy rates). The Hybrid Choice model indicates that both the frequency of car use and the possession of a public transit pass have a significant effect on the frequency of DRT use. However, this behavior is independent of latent attitudes toward different modes of transportation. Also, the service operates without a surcharge for annual pass holders, which leads to side effects such as shifting from active modes to DRT, and generating entirely new trips. Based on respondents' statements regarding alternative means of transport they would have used if DRT had not existed, we observe that DRT trips generate substantially more motorized traffic than if the service did not exist. This study provides policy recommendations aimed at increasing ridership and minimizing unintended side effects.