Shared Mobility Research

Shared mobility systems, such as bikesharing, carsharing, and ridehailing, are increasingly common in urban transportation networks. Here are some of my recent research projects about shared mobility.

1. Bikeshare Users on a Budget? Trip Chaining Analysis of Bikeshare User Groups in Chicago (2019). Authors: Yang, Brakewood, Nicolas and Sion.
Summary:  This paper focuses on a smartphone app known as “Transit” that is used to unlock shared bicycles in Chicago. Data from the app were utilized in a three-part analysis. First, Transit app bikeshare usage patterns are compared to system-wide bikeshare utilization using publicly available data. The results reveal that hourly usage on weekdays generally follows classical peaked commuting patterns; however, daily usage reached its highest level on weekends. This suggests that there may be large numbers of both commuting and recreational users. The second part aims to identify distinct user groups via cluster analysis; the results reveal six different clusters: (1) commuters; (2) utility users; (3) leisure users; (4) infrequent commuters, (5) weekday visitors; and (6) weekend visitors. The group unlocking the most shared bikes (45.58% of all Transit app unlocks) was commuters, who represent 10% of Transit app bikeshare users. The third part proposes a trip chaining algorithm to identify “trip chaining bikers.” This term refers to bikeshare users who return a shared bicycle and immediately check out another, presumably to avoid paying extra usage fees for trips over 30 minutes. The algorithm reveals that 27.3% of Transit app bikeshare users exhibit this type of “bike chaining” behavior, presumably to avoid paying additional usage fees. However, this varies substantially between user groups; notably, 66% of Transit app bikeshare users identified as commuters made one or more bike chaining unlocks.  For more information, read the paper here.

2. Qualitative Analysis of Ridehailing Regulations in Major American Cities (2017). Authors: Beer, Brakewood, Rahman, and Viscardi.
Summary: Ride-hailing services, which are provided by companies such as Uber and Lyft, are increasingly common in many American cities. Several cities are now regulating or considering regulation of these services. However, regulation has not been well documented across jurisdictions, and city planners and policy makers often want to understand what regulations are being put in place in comparable metropolitan areas. Therefore, the objective of this research was to provide a qualitative comparison of the regulations of ride-hailing companies between major American cities. This goal was accomplished through the evaluation of five driver-related and three company-related types of ride-hailing regulations in 15 major American cities.  For more information, read the paper here.

3. Sharing Riders: How Bike-Sharing Impacts Bus Ridership in New York City (2017). Authors: Campbell and Brakewood.
Summary: The objective of this research is to quantify the impact that bikesharing systems have on bus ridership. We exploit a natural experiment of the phased implementation of a bikesharing system to different areas of New York City. This allows us to use a difference-in-differences identification strategy. We divide bus routes into
control and treatment groups based on if they are located in areas that received bikesharing infrastructure or not. We find a significant decrease in bus ridership on treated routes compared to control routes that coincides with the implementation of the bikesharing system in New York City. The results from our preferred model indicate that every thousand bikesharing docks along a bus route is associated with a 2.42% fall in
daily unlinked bus trips on routes in Manhattan and Brooklyn. For more information, read the paper here.