In the New York Times of 11 June 2014 Farhad Manjoo writes:

It is impossible to say whether Uber is worth the $17 billion its investors believe it to be; like any start-up, it could fail. But for all its flaws, Uber is anything but trivial. It could well transform transportation the way Amazon has altered shopping —by using slick, user-friendly software and mountains of data to completely reshape an existing market, ultimately making many modes of urban transportation cheaper, more flexible and more widely accessible to people across the income spectrum.

Uber could pull this off by accomplishing something that has long been seen as a pipe dream among transportation scholars: It has the potential to decrease private car ownership.

In its long-established markets, like San Francisco, using Uber every day is already arguably cheaper than owning a private car. Uber says its cheapest service, UberX, is usually 30 percent less expensive than taxis.

Now that Uber, Lyft and other rivals are embroiled in a vicious match for dominance across the globe, ride-sharing prices over all are sure to plummet. The competition is likely to result in more areas of the country in which ride-sharing becomes both cheaper and more convenient than owning a car, a shift that could…reduce the need for private vehicle ownership and the environmental toll exacted by privately owned automobiles.

Paradoxically, some experts say, the increased use of ride-sharing services could also spawn renewed interest in and funding for public transportation, because people generally use taxis in conjunction with many other forms of transportation.

In other words, if Uber and its ride-sharing competitors succeed, it wouldn’t be a stretch to see many small and midsize cities become places where forgoing car ownership isn’t just an outré lifestyle choice, but the preferred way to live.

“In many cities and even suburbs, it’s becoming much easier to organize your life car-free or car-lite,”said David A. King, an assistant professor of urban planning at Columbia University who studies technology and transportation. By car-lite, Dr. King means that instead of having one car for every driver, households can increasingly get by with owning just a single vehicle, thanks in part to tech-enabled services like Uber.

Transportation scholars are just beginning to study whether the ride-sharing industry will encourage us to give up our cars, but results from some related studies look promising.

Susan Shaheen, the co-director of the Transportation Sustainability Research Center at the University of California, Berkeley, has found that car-sharing services like Zipcar and bike-sharing services have already led to a significant net reduction of car ownership among users. While she is beginning a study into whether Uber-like services have the same effect, she said it was plausible to guess that they would also reduce levels of car ownership.

“I’ve been studying this area for about 17 years, and what we’re seeing now is a ubiquity of mobile devices that is really altering this industry,”she said.

In one recent study based on GPS data from New York City cabs, Dr. King and his colleagues found that many taxi trips are “multimodal,”meaning that riders mix taxis with other forms of transportation. For instance, people from other boroughs might get to Manhattan by train, and then use cabs to return home late at night.

“The one-way travel of taxis allows people to use transit, share rides and otherwise travel without a car,”the researchers wrote. “In this way taxis act as a complement to these other modes and help discourage auto ownership and use.”

A survey commissioned by regulators in San Francisco found that if taxis were more widely available, people would use public transit more often, and would consider getting rid of one or more cars.

There’s only one problem with taxis: In most American cities, Dr. King found, there just aren’t enough of them …in many cities the number of taxis has not been increased substantially in decades, despite a vast increase in the number of miles people travel.

But Uber has done more than increase the supply of cars in the taxi market. Thanks to technology, it has also improved their utility and efficiency. By monitoring ridership, Uber can smartly allocate cars in places of high demand, and by connecting with users’phones, it has automated the paying process. When you’re done with an Uber ride, you just leave the car; there’s no fiddling with a credit card and no tipping. Even better, there’s no parking.

Compared with that kind of convenience, a car that you own —which you have to park, fill up, fix, insure, clean and pay for whether you use it or not —begins to seem like kind of a drag.

“And if your car sits there five out of seven days, suddenly you’re starting to look at that fixed cost as being a waste,”Dr. King said.