My paper "The Drivers of Social Preferences: Evidence from a Nationwide Tipping Field Experiment," with @UriGneezy, John List, and Ian Muir is now out as an NBER working paper. We analyze over 40 million tipping outcomes on the Uber app in 2017. THREAD
60% of riders who took at least 10 trips never tipped
Conditional on tipping, people tip a little more than $3 on average (about 26% of the fare), so the average tip, including cases where the rider did not tip, is about $0.50
