Analyzing the variability of public transit accessibility estimates using GPS data [Port]


Accessibility is a key concept in transport and land use integrated planning. General Transit Feed Specifica0on (GTFS) data have been successfully used in recent years as input to measure accessibility levels, but it is based on scheduled transit trips to estimate travel time between origin-destination pairs. On the other side, GPS data have been applied to update actual trip time tables, although with methodological and computational limitations, based on travel time measures of central tendency to reconstruct the GTFS file. Using one month of GPS bus data in Fortaleza, this work analyzed the variability of accessibility through empirical travel times, considering its dispersion. The results show that there is a significant variability in the estimation of the accessibility indicators, both in space and between work and school activities, possibly affecting the assessment of interventions on the transportation system..