The Development of a New Location-Based Accessibility Measure Based on GPS Data

Area of Science:

• Transportation Science
• Urban Planning
• Geographic Information Systems

Background:

• Sustainable transport network management relies heavily on accessibility.
• Conventional accessibility measures often use only average travel times, ignoring crucial travel time distributions.
• This simplification leads to inaccurate accessibility assessments, especially in dynamic traffic conditions.

Purpose of the Study:

• To develop and validate a novel accessibility measure that incorporates travel time probability density distributions.
• To quantify the impact of travel time variability on accessibility estimations.
• To compare the proposed method with existing potential accessibility calculations.

Main Methods:

• Developed a new accessibility model integrating travel time probability density functions.
• Utilized GPS data from taxis in Harbin, China, for analysis.
• Compared accessibility results from the novel method against conventional potential accessibility calculations.

Main Results:

• The proposed method revealed that existing accessibility measures underestimated accessibility by 6-28% (average 17%) across 103 study zones.
• Inaccuracies in conventional methods led to the misclassification of 20% of urban areas with low accessibility.
• The novel approach demonstrated higher sensitivity to real-world traffic conditions.

Conclusions:

• Conventional accessibility measures provide biased and misleading estimations due to their neglect of travel time variability.
• The travel time variability-integrated accessibility measure offers a more accurate and objective assessment of transportation network performance.
• This improved assessment is crucial for effective sustainable transport planning and management.