Measuring Traffic Congestion with Taxi GPS Data and Travel Time Index

摘要

In an era of increasing urban traffic congestion, cities in China still lack a comparable congestion indicator. Aiming to fill this gap, we computed the travel time index (TTI) with taxi GPS data. Our TTI is the ratio of the travel time during the period of interest to the travel time during free-flow conditions. Using Shenzhen as the case study, we computed road level TTI for nearly 10,000 roads. The GPS data, which tracks the movement of 13,798 taxies, are processed in a PostgreSQL database. Our method can measure urban transportation congestion with fine-grained spatial and temporal accuracy, and has the potential to be used in other cities.