LAUSR

Abstract Carpooling rates in America have been falling for decades. But new technologies may offer solutions to traditional carpooling barriers and usher in a new chapter in shared car travel. Ride-hail services connect riders to drivers through smartphone applications. The largest ride-hail companies, Uber and Lyft, offer shared carpool (rideshare) services to connect riders traveling in the same directions and at the same times. Although researchers have recently begun to understand who uses ride-hail services, few have yet investigated ridesharing. To fill this gap, I ask and answer two questions. First, what factors are associated with where ridesharing occurs? Second, what factors are associated with who rideshares? To answer both questions, I use trip-level data of 6.3 million Lyft trips, including 1.9 million Lyft Shared trips, taken in Los Angeles County in 2016. Findings reveal that while about one-third of Lyft trips are on Lyft Shared, these rideshare trips are made by a small fraction of ride-hail users. Just one-third of ride-hail users made even one rideshare trip over the three-month study period, and just ten percent of all Lyft riders made 94 percent of rideshare trips. People living in dense and lower-income neighborhoods share a higher proportion of ride-hail trips compared to riders living in other neighborhoods. Less ridesharing occurs in racial and ethnically diverse neighborhoods compared to neighborhoods where clear racial or ethnic majorities exist. Cities seeking to increase sharing in ride-hail services should focus efforts on attracting non-users, including pricing to encourage shared rather than solo car trips. Implemented policies should avoid undercutting demand for transit or active travel, which remain the most efficient modes on our streets.