I am very glad to share our new paper looking at the travel time gap between private and public transport at high spatial and temporal resolutions. The study combines real-time traffic data, transit data, and travel demand estimated using Twitter data to compare this travel time gap in four cities (São Paulo, Stockholm, Sydney and Amsterdam).
Despite remarkable differences between these cities in terms of transportation networks, area, and population size, we found travel times of transit and vs. driving are surprisingly similar across cities: R < 1 for trips shorter than 3km, then increases rapidly but quickly stabilizes at 2 (figure below). Moreover, using public transport generally takes on average 1.4–2.6 times longer than driving a car. The share of area where travel time favors public transport over car use is also very small in all cities. As Giulio Mattioli noted on Twitter, these results 'would confirm that car dependence is much more than just a question of culture & attitudes'.
Despite remarkable differences between these cities in terms of transportation networks, area, and population size, we found travel times of transit and vs. driving are surprisingly similar across cities: R < 1 for trips shorter than 3km, then increases rapidly but quickly stabilizes at 2 (figure below). Moreover, using public transport generally takes on average 1.4–2.6 times longer than driving a car. The share of area where travel time favors public transport over car use is also very small in all cities. As Giulio Mattioli noted on Twitter, these results 'would confirm that car dependence is much more than just a question of culture & attitudes'.
The paper is open access and it was written in collaboration with a great team led by Yuan Liao and Sonia Yeh at University of Chalmers, Sweden.
Liao, Y., Gil, J., Pereira, R.H.M. et al. Disparities in travel times between car and transit: Spatiotemporal patterns in cities. Scientific Reports 10, 4056 (2020). https://doi.org/10.1038/s41598-020-61077-0
Abstract:
Cities worldwide are pursuing policies to reduce car use and prioritise public transit (PT) as a means to tackle congestion, air pollution, and greenhouse gas emissions. The increase of PT ridership is constrained by many aspects; among them, travel time and the built environment are considered the most critical factors in the choice of travel mode. We propose a data fusion framework including real-time traffic data, transit data, and travel demand estimated using Twitter data to compare the travel time by car and PT in four cities (São Paulo, Brazil; Stockholm, Sweden; Sydney, Australia; and Amsterdam, the Netherlands) at high spatial and temporal resolutions. We use real-world data to make realistic estimates of travel time by car and by PT and compare their performance by time of day and by travel distance across cities. Our results suggest that using PT takes on average 1.4–2.6 times longer than driving a car. The share of area where travel time favours PT over car use is very small: 0.62% (0.65%), 0.44% (0.48%), 1.10% (1.22%) and 1.16% (1.19%) for the daily average (and during peak hours) for São Paulo, Sydney, Stockholm, and Amsterdam, respectively. The travel time disparity, as quantified by the travel time ratio R (PT travel time divided by the car travel time), varies widely during an average weekday, by location and time of day. A systematic comparison between these two modes shows that the average travel time disparity is surprisingly similar across cities: R < 1 for travel distances less than 3 km, then increases rapidly but quickly stabilises at around 2. This study contributes to providing a more realistic performance evaluation that helps future studies further explore what city characteristics as well as urban and transport policies make public transport more attractive, and to create a more sustainable future for cities
The relationship between travel distance and travel time ratio R (PT travel time divided by the car travel time)
