Ride-sharing apps like Uber and Lyft are designed to make it easier for anyone to get a car on demand, but some passengers are occasionally being left in the dust. African-American riders face longer wait times and endure more ride cancellations than others, according to the results of a new study.

Past research has documented that racial discrimination exists in traditional taxi services, and the authors of the latest study examined whether ride-sharing services reduced some of the historical biases found within the cab industry.

"We want to, as much as possible, stress that we're not in the study claiming that Uber and Lyft are any worse than the status quo," Christopher Knittel, study co-author and professor at the MIT Sloan School of Management, told Seeker. But based on the researchers' findings, both Uber and Lyft have room to improve.

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For their study, researchers at the Massachusetts Institute of Technology, Stanford University and the University of Washington sent assistants in Seattle and Boston to hail nearly 1,500 rides, chosen at random days, times and routes, through Uber and Lyft.

In Seattle, eight research assistants, split evenly among race and gender, collected the time it took for a ride to be accepted as well as how long it took the driver to pick them up. For the black participants, there was a statistically significant longer wait time, upwards of 35 percent longer, for a ride to be accepted for both Uber and Lyft.

Looking at just how long it took for the driver to show, only Uber showed a longer wait time for the African-American passengers.

In Boston, instead of eight participants, the field team had two different devices, one with an "African American-sounding" name and another with a "white-sounding" name. As soon as a ride was accepted, the research assistants took a screenshot, and once again when the driver actually showed in order to find out if there was a difference between the two, suggesting a cancelled ride. Using an "African American-sounding" name more than doubles the probability of a ride cancellation.

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In the case of female passengers, women on average in Boston were taken on longer rides than men, which surprised researchers because they didn't design the experiment to measure it. Two potential explanations are that riders either wanted to get a higher fare or, based on some anecdotal evidence, the drivers were trying to use the fare as a "social opportunity," Knittel said.

So what can ride-sharing apps do to prevent racial discrimination among its drivers? Getting rid of names and/or photos of the riders would be one possibility that Knittel and his co-authors suggest.

"You could imagine — and we're not advocating for this necessarily — a transportation service company that just gives you a code, or some non-descript saying or phrase," Knittel said. "The cost of doing that is that people like to know who's getting in their car," Knittel added.

Certainly part of the appeal of ride-sharing services is having a sense of the other person in the car. Other possible measures that the researchers suggest include periodic auditing of drivers' behavior, fixed pricing offered upfront between pickup and drop-off locations, and increasing the disincentives for drivers cancellations.

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