Measuring place-based accessibility under travel time uncertainty

ABSTRACT

Travel time uncertainty has significant impacts on individual activity-travel scheduling, but at present these impacts have not been considered in most accessibility studies. In this paper, an accessibility evaluation framework is proposed for urban areas with uncertain travel times. A reliable space-time service region (RSTR) model is introduced to represent the space-time service region of a facility under travel time uncertainty. Based on the RSTR model, four reliable place-based accessibility measures are proposed to evaluate accessibility to urban services by incorporating the effects of travel time reliability. To demonstrate the applicability of the proposed framework, a case study using large-scale taxi tracking data is carried out. The results of the case study indicate that the proposed accessibility measures can evaluate large-scale place-based accessibility well in urban areas with uncertain travel times. Conventional place-based accessibility indicators ignoring travel time reliability can significantly overestimate the accessibility to urban services.

KEYWORDS:

• Place-based accessibility
• service area analysis
• travel time uncertainty
• reliability

Acknowledgments

The authors are thankful to the editor and anonymous referees for their comments and suggestions that improved this paper.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [41571149], [41231171], Research Committee of the Hong Kong Polytechnic University [87PV] [1-BBA8], Research Institute of Sustainable Urban Development of the Hong Kong Polytechnic University, [1-ZVEW].