A new joint study from researchers at the Massachusetts Institute of Technology (MIT), the University of Washington and Stanford University found what many Uber and Lyft users already know: some drivers discriminate against customers they perceive to be Black.

While some people of color use ride apps to avoid taxi driver bias, “Racial and Gender Discrimination in Transportation Network Companies” found that Black users wait longer to get rides and are more likely to have their rides cancelled than other users.

Research assistants ordered 1,400 rides in Seattle and Boston using “transportation network companies” (TNC) like Uber and Lyft, then evaluated the process. The controlled experiments used randomly selected days, times, routes and riders. In Seattle, passengers who were perceived to be Black consistently waited up to 35 percent longer for rides. In Boston, men with “African American-sounding names” saw their rides canceled more than twice as often as when those same men used “White-sounding names” to book their trips.

“The patterns of discrimination were quite clear and consistent in both cities—and one can only assume it’s happening all across the country in other markets,” Christopher R. Knittel, study co-author and professor at the MIT Sloan School of Management, said in a press release. “The study has found major areas of racial discrimination within this new industry. It’s quite concerning.”

Uber drivers see names after accepting a fare, why Lyft shows drivers the names and faces of potential drivers before they make a decision. In an interview with Bloomberg, the researchers offered some suggestions for decreasing the bias:

The researchers proposed changes that Uber and Lyft could make to reduce discrimination, including not identifying passengers’ names, more severe repercussions for drivers who cancel after accepting a ride and periodic reviews of drivers’ behavior to look for racism.

Bloomberg reached out to Rachel Holt, Uber’s head of North American operations, for a statement. “Discrimination has no place in society and no place on Uber,” Holt said. “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.”