Tag Archives: ride sharing

AAA study finds car ownership better than ride sharing

My headline above is true, but misleading. What AAA really did is answer the question under what conditions owning a car is cheaper than ride sharing, and there are some. AAA found that owning a car can be more cost-effective than ride sharing…for people who drive about a thousand miles a month, have “free” parking, and choose a used car. That may indeed describe the average suburban American, and I am not criticizing people who choose that life style. But in my opinion, many people do not choose it but default to it without realizing other options are possible.

I live in a dense city (in a single family home with a small front and back yard, not a high rise apartment.) My family walks for most work, school, and shopping trips. Street parking is cheap but scarce, and garage parking is very expensive (you can’t have cheap, abundant parking and high density together.) Ride sharing has been a great innovation for the occasional trips where a car is the best option, and particularly great for getting home from somewhat far-flung places where calling a taxi used to be a very unreliable and expensive option. We simply don’t worry about getting stranded places any more, which used to be the single most annoying thing about not owning a car. I guess that means we take a few trips now that we wouldn’t have in the past, and if enough people are doing that it explains why ride sharing has increased traffic a little bit – and why that is a good thing.

Anyway, my point is that the AAA conclusion is not a general one that would apply to my situation. And my situation is one that anyone can choose to be in, maybe not tomorrow but if you want to live in a high-density, walkable residential area you can plan that and make it happen within a few years.

Lyft v. parking

I seem to be on a safe streets, anti-car roll this week so I’ll keep rolling. This article quotes a Lyft spokesman and drivers about how people are using ride sharing services to avoid having to deal with parking.

“They say, ‘I can’t afford to park down there,’” Gregory Goodman said. “And if they end up parking down there they end up with a $75 ticket.”

Lyft Philly GM Andrew Woolf confirmed that a significant portion of Lyft’s business comes from people who don’t want to park their cars. This has become a trend for commuters elsewhere, too, so much so that office landlords in New Jersey are beginning to offer Lyft and Uber subsidies.

Much of the time, these trips to avoid parking are to the airport or SEPTA stations, but Lyft is used for far more routine parking jobs.

I think this is slightly missing the point. The point of transportation is to get where you need to go, when you need to go there, at a reasonable financial price. People in relatively compact cities have always had more options in this regard than everyone else – walking, biking, public transportation, and taxis. On any given day, someone may decide one of these options is cheaper and/or more convenient than driving and parking their private vehicle. Others are going to decide that having a private vehicle is no longer worth the trouble (count me in this camp, since 2004). But Uber and Lyft are game changing because they are a much better option in many cases than these older options, and in less dense communities they are providing the first viable alternative to private vehicles that people have ever had access to. So people are making their choices.

Like I said, I haven’t owned a private vehicle since 2004. But I used to rent cars and use share cars (the kind you sign out and drive yourself) frequently, but lately I hardly ever do either of these things. I take Uber and Lyft instead. Here in Philadelphia, our public transportation agency is set to raise fares yet again to a minimum of $2.50, and they need to be careful because Uber Pool and the Lyft equivalent (I forget what it’s called) are going to be competitive for some rides. So it could be the beginnings of a public transportation death spiral. What they need to do, of course, is adopt the Uber Pool type technology to public transportation, and offer flexible routes and timing. All is not quite perfect in corporate Uber land, of course, and public transportation agencies could actually take advantage of this if they are smart and flexible enough. But I wouldn’t put my money on that.

There is still an irony when we talk about parking. Gradually, fewer private cars will mean less parking demand and less competition for the parking spaces we have already built, or that we will continue to build through misguided policies in some places. That will mean less angst about parking and actually provide some counter-incentive to giving up your private vehicle, so at some point it will settle into some kind of equilibrium, at least until the next technological disruption or in a few progressive places that realize they can use all that land for something better than parking.

ride pooling can (maybe) reduce traffic by a lot

Here’s a new study from MIT that says ride sharing and pooling algorithms could theoretically reduce Manhattan rush hour traffic drastically.

On-demand high-capacity ride-sharing via dynamic trip-vehicle assignment

Ride-sharing services are transforming urban mobility by providing timely and convenient transportation to anybody, anywhere, and anytime. These services present enormous potential for positive societal impacts with respect to pollution, energy consumption, congestion, etc. Current mathematical models, however, do not fully address the potential of ride-sharing. Recently, a large-scale study highlighted some of the benefits of car pooling but was limited to static routes with two riders per vehicle (optimally) or three (with heuristics). We present a more general mathematical model for real-time high-capacity ride-sharing that (i) scales to large numbers of passengers and trips and (ii) dynamically generates optimal routes with respect to online demand and vehicle locations. The algorithm starts from a greedy assignment and improves it through a constrained optimization, quickly returning solutions of good quality and converging to the optimal assignment over time. We quantify experimentally the tradeoff between fleet size, capacity, waiting time, travel delay, and operational costs for low- to medium-capacity vehicles, such as taxis and van shuttles. The algorithm is validated with ∼3 million rides extracted from the New York City taxicab public dataset. Our experimental study considers ride-sharing with rider capacity of up to 10 simultaneous passengers per vehicle. The algorithm applies to fleets of autonomous vehicles and also incorporates rebalancing of idling vehicles to areas of high demand. This framework is general and can be used for many real-time multivehicle, multitask assignment problems.

There are plenty of criticisms of this type of study. The major one is that if you make a particular transportation option faster and/or cheaper, economics dictates that people will automatically switch to it from other options over time, eventually making it less fast and/or less cheap until the various modes are balanced again. The study above (based on my quick skim of the abstract) probably took data from one or a few Manhattan rush hours and asked how it could be rerouted in the most efficient possible way. I don’t fault them for doing the study, which is really interesting. The economics and human behavioral feedback loops that happen over longer periods of time just need to be studied too before policy decisions are made based on results like these.

I don’t necessarily want UberPool to be the answer to all our infrastructure problems. I love the idea of subway and above-ground rail and bus rapid transit as much as the next person. But as the opening of the most recent segment of New York subway recently showed us, these projects are taking decades to build in the U.S. and costing enormous amounts of money. Europe and Asia are doing much better than us, so maybe we could learn some lessons from them, but our recent political challenges shed some doubt on the idea that we can improve any time soon. (Europe generally manages to do somewhat better with high-wage union labor, while some Asian countries build extremely cost-effectively by issuing temporary work visas to low-wage labor from developing countries. There are political and moral issues on both ends of this spectrum, obviously, but the point is the U.S. doesn’t do either approach well. Much like our health care system, we spend 2 or 3 or 5 times more than everyone else and get worse results.)

If the criticism of the study I mentioned above is that demand projections made before the new infrastructure options or technologies are in place are not going to be accurate, that criticism certainly applies to a subway system that takes decades to build. The entire population, land use, and employment pattern of the area served could change in that time, not to mention that whatever technology is chosen is almost guaranteed to be obsolete the day operation begins. With the ride-sharing algorithms, even if the projections are wrong at first at least you have a system that should be easy to adapt and tweak over time. I don’t see why public bus systems and bus rapid transit can’t be integrated into a system like this. And if people want a vehicle to themselves for some trips sometimes, the algorithms and pricing schemes should be able to accommodate that. You could even imagine an algorithm managing passenger vehicles, freight and delivery vehicles in urban areas so they are less in conflict with other at various times of day and night. The algorithms could be run by government or non-profit entities if we are really afraid of private control, or private algorithms and entities could be forced to communicate and coordinate with one another.