"Do ride-hailing companies like Uber and Lyft make a city's traffic worse or better?
In San Francisco at least, the answer is decidedly worse, according to a newly published study in the journal Science Advances.
'It's by far the most detailed look that's been done in any given city,' says Bruce Schaller, a transportation expert and former New York deputy commissioner for traffic and planning who was not involved in the study. 'And it's certainly consistent with what we're seeing in other places.'"