Alex Tabarrok at MR:

What is the effect of tipping on the take-home pay of Uber drivers? Economic theory offers a clear answer. Tipping has no effect on take home pay. The supply of Uber driver-hours is very elastic. Drivers can easily work more hours when the payment per ride increases and since every person with a decent car is a potential Uber driver it’s also easy for the number of drivers to expand when payments increase. As a good approximation, we can think of the supply of driver-hours as being perfectly elastic at a fixed market wage. What this means is that take home pay must stay constant even when tipping increases.

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At this point many readers will object that I am a horrible person and this is all theory using unrealistic “Econ 101” assumptions of perfectly competitive markets, rationality, full information etc etc. To which my response is that the first claim is plausible but irrelevant while the second is false. A new paper, Labor Market Equilibration: Evidence from Uber, from John Horton at NYU-Stern and Jonathan Hall and Daniel Knoepfle, two economists at Uber, looks at what happens when Uber increases base fares.