CHICAGO, Feb. 20 (Xinhua) -- A study led by University of Chicago (UChicago) economists found that men working for ride-sharing platform Uber earned about 7 percent more per hour than women.

Examination of driving records of 1.8 million drivers in 196 U.S. cities, more than 500,000 or 27 percent of whom were female, found that men in the study earned 21.28 dollars an hour while women were paid 20.04 dollars an hour.

The study found that male drivers work more: 17.98 hours a week compared to 12.82 a week for women. This gives men an edge in learning how to choose potential passengers based on how far the driver has to travel to pick them up, the distance to the intended destination and other factors that can influence pay.

The study also found that, until about their 2,500th trip, drivers are learning those skills that can maximize pay. A fully experienced driver earns about 3 dollars more an hour than a driver with 500 or fewer trips.

Men were more likely to drive in areas and during times in which pay is higher; and men drive 2.2 percent faster than women working for Uber, which increases the number of trips they can fit into the hours they work.

Any changes Uber might make to try to close its wage gap might be counterproductive, said John A. List, a professor in economics at UChicago. The current system rewards experience, which he said "is good for everybody."