Shifting Travel from Ride-Hailing to Ride-Sharing 

Abstract
Transportation network company (TNC) platforms, like Uber and Lyft, claim to be the future of sustainable transportation because they enable users to live a car-free lifestyle and offer new mobility options for those unable to drive through ridehailing and ridesharing. Although the concept of ridehailing and ridesharing promise a sustainable future, the large majority of Uber and Lyft ridehails only serve one user resulting in additional traffic congestion and emissions. For efficient use of the roadway, users must shift travel from ridehailing toward ridesharing.
Shared usage is dependent on linking travelers to one another and their willingness to share the ride. Traditional factors such as time and cost are essential to users willingness to take a shared ride (Chen, 2018). In the future, the majority of the performed urban rides could be easily linked with individuals incurring in very little extra time and cost disutility (Van Hentenryck, 2018). The factors associated with social interactions will become an increasingly important factor in understanding a user's willingness to share a ride. A number of studies have developed the notion of willingness to share (WTS) as a way to quantify this social interaction factor in mode choice. WTS has been modeled as the money value attributed by an individual traveling alone compared to riding with strangers through stated choice scenarios surveys (Lavieri and Bhat, 2019) (Alonso-González, 2019). Through the combined analysis of multiple data sources, this study evaluates the characteristics of commuters as related to their willingness to share a ride. Combined surveys had different purposes but all included questions related to an individual's comfort around strangers, experience in a sharing environment, and the preference of ridesharing. Early results from descriptive statistics indicate that people are more comfortable riding with many strangers than with a few strangers in a rideshare. This means that interpersonal problems with ridesharing would persist in autonomous vehicles. Further modeling work will be completed to assess and develop situations in which people are willing to share space. By understanding which people are willing to share space, this study continues to shift travel from ride-hailing toward ride-sharing.