Uber and Lyft drivers are quietly discriminating against riders based on gender and race, according to a study published on Monday.
The study, from professors at the Massachusetts Institute of Technology, Stanford University and the University of Washington, found drivers for ride-hailing services treat women and black people differently from white men.
The data came from 1,500 rides hailed in Seattle and Boston.
In Seattle, black people waited longer for Uber and Lyft drivers to accept their ride requests, and black riders waited up to 35% longer to be picked up by their UberX drivers. However, in Boston, some Uber drivers didn't even pick up black passengers.
"Across all trips, the cancellation rate for African-American sounding names was more than twice as frequent compared to white-sounding names," according to the report.
"We went into this hoping that we wouldn't see anything, but we found pretty strong evidence of discrimination," study co-author Christopher Knittel, a professor at MIT Sloan School of Management, told CNNMoney.
The study also revealed gender impacted travel times, too.
"Other female riders reported 'chatty' drivers who drove extremely long routes, on some occasions, even driving through the same intersection multiple times," the study noted. "As a result, the additional travel that female riders are exposed to appears to be a combination of profiteering and flirting to a captive audience."
It's unclear why female passengers were kept in cars for a longer time, but some factors could be for social reasons or to charge a higher fare, Knittel said.
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The report recommended several solutions to fix the problem which include: up-front fares (which Uber has started to roll-out), implementing harsher consequences for drivers who cancel after accepting a rider and not displaying the rider's name in the app.
Lyft and Uber have responded to the study with similar statements.
"We believe Uber is helping reduce transportation inequities across the board, but studies like this one are helpful in thinking about how we can do even more," said Rachel Holt, Uber's head of North American operations in a statement.
Meanwhile, Adrian Durbin -- Lyft's director of policy communication -- responded to the study by highlighting its positive impact on "communities of color."
"We are extremely proud of the positive impact Lyft has on communities of color. Because of Lyft, people living in underserved areas - which taxis have historically neglected - are now able to access convenient, affordable rides," Lyft's Director of Policy Communications Adrian Durbin told CNNMoney in a statement.
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