Comparison of Smartphone based Cyclist GPS Data Sources
It is important for planning agencies to have data on cyclist travel patterns, routes, volumes, and speeds, but access to such data is currently limited and often expensive to obtain. Many regions are looking toward the use of GPS data collected using smartphones to track cyclist trips, both via apps deployed by the agencies and, more recently, fitness based apps providing anonymized user data by roadway segment. As regions begin to collect and purchase GPS based data, there are many questions about potential uses in transportation planning, including the representativeness of the data. This paper provides a comparison of the data obtained from two smartphone based apps, Cycle Atlanta and Strava, to begin to understand how GPS data can be used to map cyclist movements in an urban area. Analysis includes user demographic data and overall trip statistics, time of day, and geographic trips by segment comparisons. Differences between the two populations were found in terms of gender, age, percent commute trips, trip lengths, and preference for bike paths. Cycle Atlanta data was also compared to a set of manual bike counts and it was found that only about 3% of the cyclists counted had recorded their trip in Cycle Atlanta. The usage of GPS based smartphone cycling app data is a promising new data source for transportation planning and design analysis, but should carefully take into account the likely bias from the self selected users of such apps. These apps can supplement, but not replace large scale count programs to establish system wide cyclist volumes.