As IPO soars, can Uber and Lyft survive long enough to replace their drivers with computers?

Millions of drivers are betting their livelihoods on Uber and Lyft. On Friday, Wall Street bet billions of dollars that the companies won't need those drivers. Lyft and Uber, which helped pioneer the gig economy with its armies of drivers, lose massive amounts of money to pay drivers for each ride. The firms could slash their costs of each ride by as much as three-quarters by replacing human drivers with autonomous vehicles, according to the companies, turning ride-hailing into a profitable enterprise. But widespread deployment of the technology is a decade away at best, experts say.