Frequency is the key to van success

Anna Gustafson of Yournabe had a nice report on the van pilot press conference, and asked a key question that nobody else seems to have bothered with:

For riders on the Q74 line, vans will run weekdays from 6 a.m. to 10 p.m., making stops every 15 minutes during the rush hours of 6 a.m. to 10 a.m. and 30 minutes at all other times. On weekends, vans will run from 6 a.m. to 8 p.m. and make stops every 30 minutes.

[...]

Along the Q79 route, vans will run weekdays from 6 a.m. to 8 p.m. and make stops every 15 minutes during the rush hours of 6 a.m. to 10 a.m. and 3 p.m. to 8 p.m. and 30 minutes at all other times. Rides will be available on weekends from 8 a.m. to 6 p.m. and will make stops every 30 minutes.

Let me say right away that I have my doubts as to whether these frequencies will actually be adhered to. But if they are, it would essentially doom these services. Jarrett explains why low frequency drives people away:

Frequency is best described by headway, the elapsed time between consecutive trips on a line. The headway is also the maximum waiting time, and half of it is the average waiting time. Add those to the much-advertised travel time (technically called in-vehicle travel time or IVTT) and you have a sense of how long a real-life trip will be. And those are the realities that will ultimately drive ridership.

Let's imagine a Queens College student who gets off the E train at 10:00 AM. The headway is thirty minutes, making the average wait time fifteen minutes. Google says that it takes nine minutes to drive from the subway to the college, and if we add five minutes for picking up and dropping off other passengers, it's about half an hour total time.

However, Google also says that our student can get to college in half an hour by getting back on the E train and taking the Q88 bus from Forest Hills. In fact, it's probably a lot less than that, because our student is already on the train, so they either get off one stop early or one stop later and catch the Q64. That bus has fifteen minute headways and eighteen minute in-trip time, for a total of 25 minutes.

What this means is that if the vans can't offer a headway of fifteen minutes or less, they might as well pack up and go home. You can do similar calculations for the Q79 and the Brooklyn runs. Long-distance private bus services like Coachusa can run on half-hour headways because they've got a near monopoly and a customer base that has been riding these lines for almost a hundred years; these vans can't count on anything like that.

As I said before, I'm not sure that these headways were anything other than a way to give Gustafson an answer without getting into a long discussion on jitney economics. It may be that Ricketts is planning on anchoring the cascade himself at these headways, but that he plans on adding vans whenever there are enough passengers to make it worthwhile.

With a private service, however, that anchor has to be cross-subsidized by other runs; otherwise it's just a waste of money and eventually it will be shut down. The pilot program runs for ninety days, which means that if ridership hasn't risen to profitable levels by December 20, the vans will go back to Jamaica and Flatbush. What are Ricketts and the Taxi and Limousine Commission doing to make sure that it does rise?