What Does “On Demand” Mean, Anyway?
One of the tech industry’s buzzwords for transportation is “on demand” – that is, available to the passenger immediately, without fixed schedules. When I said something about schedules at my Hyperloop One interview, the interviewers gently told me that actually, they intend their system to be on-demand; I forget what I said afterward, but I do remember I didn’t press the point. More commonly, people who insist on using ride-hailing apps rather than public transit talk about how great it is that they don’t have to follow fixed schedules.
But what does this really mean? Calling a cab, or hailing one via a TNC app, does not mean it comes immediately. There’s a wait time of several minutes. How many minutes depends on time of day and which city one is in. A Dallas air travel blog describes wait times of around 10 minutes. In and around Boston, Patreon supporter Alexander Rapp says “2-7 minutes is the typical range” with New York waits slightly longer. In Los Angeles, a dissertation studying racial bias finds that the average predicted wait times are 6-7 minutes for black people and 5-6 minutes for others (PDF-p. 147); both the absolute numbers and the difference are much higher for street-hailed cabs. In 2014, the median wait time in New York was 3 minutes.
On an urban transit line, an average wait of 10 minutes is equivalent to a 20-minute frequency, and an average wait of 5 minutes is equivalent to a 10-minute frequency. At the lower end, the fixed schedule is actually better – a well-run transit system with 20-minute frequencies publicly posts clockface schedules and sticks to them, so people know in advance how to time themselves to the bus or train’s arrival time.
Even the wait times of 2014’s New York, not since achieved in the city or elsewhere, are only equivalent to a subway train that comes every 6 minutes, which is decidedly mediocre. The outer subway branches in New York get a train every 8-10 minutes off-peak, but they are not what TNCs compete with. Bruce Schaller’s report alleging that TNCs are responsible for the decline in subway ridership uses data from mid-2016, when 56% of TNC trips in New York were in Manhattan south of West 110th and East 96th Streets and another 22% were in inner-ring neighborhoods, mostly before the subway branch points. And subway frequency in New York is not good for how busy the system is; during the daytime, longer headways than 5 minutes are rare on the Paris Metro and on the trunks in London and Stockholm. Milan, hardly a transit city, runs its driverless metro line every 4 minutes off-peak.
All of the comparable waits get longer outside the city. Stockholm’s highly-branched metro system runs every 10 minutes on some branches off-peak, and Tube waits go up to 10 minutes on some branches as well. Commuter rail waits start from 10 minutes on the busiest branches, like those of the RER A, and go up from there, sometimes even to a train every half hour off-peak in suburbs of respectable European transit cities. But the branches are not where people ride TNCs. Just as in New York the vast majority of TNC trips are downstream of the branch points, in London as of 2013, 74% of taxi trips were within Inner London; if New York’s subsequent evolution is any indication, TNC traffic is somewhat less dominated by the center, but has only differed from street-hailed cab traffic patterns in degree rather than kind.
This calculation does not mean that transit is better than TNCs on out-of-vehicle times. It is not. Walk times to stations are considerable. Trips that require transfers have extra wait time. In New York, there appear to be about 1.6 unlinked trips per linked trip, but most likely multiple-seat rides have shorter waits on average, because they include local-express transfers, which passengers make preferentially if the waits are short. In London, judging by the origin-destination matrix, 61% of trips do not require any interchange, and another 34% require just one. So even with transfers, frequent subways are still a little bit ahead, but then the walk time to the station makes a big difference in favor of TNCs.
But here’s the thing: tech workers who talk about the greatness of on-demand transportation do not talk about station access time. Evidently, Hyperloop One, which has to use stations, talks about on-demand service. The company did try to think about how to branch in the cities in order to reduce station access time, but reduce does not mean eliminate. Moreover, the same kind of branching is already available to trains and even more so to intercity buses, and yet they rarely make use of it: intercity buses do not make milk runs within cities, leading to awkward situations in which a person in Upper Manhattan traveling to Boston has to take the subway to Midtown and then get on a bus that slogs through Manhattan streets going toward Upper Manhattan on its way to the freeways to Boston.
So what’s going on here? There’s a legitimate advantage to cars over transit in that they don’t require you to travel to a subway station or transfer, but that’s not the argument that opponents of transit who talk about TNCs and app-hailed services and on-demand travel make. They talk about wait times, never mind that well-run urban transit offers shorter wait times than app-hailed TNCs.
My suspicion is that this involves business culture. Urban transit is extremely Fordist: it has interchangeable vehicles and workers, relentlessly regular schedules, and central allocation of resources based on network effects. The tech industry has corners that work like this as well, like Amazon’s monitoring its warehouse workers’ bathroom breaks, but for the most part the industry comes from a post-Fordist world. The idea that there should be people writing down precise schedules for service is alien, as is any coordinated planning; order should be emergent, and if it doesn’t work at the scale of a startup, then it’s not worth pursuing.
There have been positive examples of using better software technology to improve public transportation. The Internet itself has been amazing at improving access to information; the single most important technology for transit reform in lagging regions like North America is Google search, followed by Wikipedia, and even in places with healthy transit these tools are valuable. Within schedule planning, new software tools make it easier to track delays. Tech is a tool, and as such it has been very useful for transit, as for many other industries.
However, all of this occurs within the usual culture of transportation planning. In contrast with this culture, most companies that produce software use a culture of startups, which have to work at a small scale to get anywhere. Where network effects are required, as with social media, it’s necessary to find a small, high-prestige network of early adopters, e.g. Harvard students for Facebook. Anything that requires more initial capital than a VC is willing to risk on a single firm is out; thus Hyperloop One views itself as a consultancy developing a technology rather than as a railroad actually building its own Hyperloop infrastructure.
A corollary of this is that people within the tech industry dismiss schedules out of hand. Thus they insist that transportation be on-demand, even when in practice the wait is longer than on a competing mode of travel that is scheduled. The idea of on-demand travel is reassuring, and because Swiss scheduling precision is alien to the American tech entrepreneur, it’s not a big deal if on-demand means a promised 5-minute wait and an actual 10-minute wait.
But what reassures the tech entrepreneur does not reassure the average rider. By overwhelming numbers, people who have a choice between even mediocre public transportation and TNCs slog through 9-minute bus and train frequencies; people who have access to good public transportation keep taking it where available. In New York, where transit isn’t even that great by the standard of large European cities, there is an ongoing panic about a 2% decline in annual subway ridership, which Schaller wrongly attributes to TNCs rather than to internal decline in subway service quality. Ultimately, the experience of waiting a few minutes for a train is annoying and passengers try to avoid it, but over time they don’t find it any more annoying than the experience of waiting for the app-hailed car driver to show up. Rhetoric about on-demand service aside, passengers do notice how long they’re actually waiting.

