D&S researcher Alex Rosenblat expands on the work of “Discriminating Tastes: Customer
Ratings as Vehicles for Bias if Uber ratings discriminate against drivers” in this New Scientist piece.

The trouble is that many passengers may not understand how important the ratings are to drivers, or which criteria Uber expects users to consider, says Rosenblat. People might think that a four-star rating is good, for example. But as drivers risk being kicked off the platform if their average score drops below 4.6, anything under the maximum five stars constitutes a failing grade.