Pittsburgh Bus Bunching (2016) • Hacker News Board

Re: Pittsburgh Bus Bunching (2016)

#61

Post by pm24601 » Tue, Jul 24, 2018, 4:32 PM UTC

mnw21cam wrote: post #52

et-al wrote: post #14

On a tangental note, another HN user posted another visualisation a few months back which I quite enjoyed: Why do buses bunch? : http://setosa.io/bus/

Indeed. You can do all sorts of complicated analysis of where, when, and how frequently buses bunch. But the explanation is very simple - like magnets, buses attract each other, in a positive feedback loop. As long as the waiting time at each bus stop depends on the number of passengers that have to get on and off, then buses will always bunch. This is caused by the bus schedule being tight, so the bus has to keep on…

In Boston on the T-lines they will just announce that the subway is expressing to skip the next two stations. Every one who wants to get off at the skip station needs to exit and catch the train behind.

Re: Pittsburgh Bus Bunching (2016)

#62

Post by stephengillie » Tue, Jul 24, 2018, 8:33 PM UTC

mnw21cam wrote: post #58

stephengillie wrote: post #56

Earlier quoted context omitted.

> "you're too close to the bus in front, wait a bit at the next stop" That's one way to infuriate the passengers on the waiting bus.

Not if it's something like 20 seconds.

Those will be a very tense 20 seconds. A big sign with a clock will help manage those expectations.

Re: Pittsburgh Bus Bunching (2016)

#63

Post by rident » Wed, Jul 25, 2018, 3:14 AM UTC

mnw21cam wrote: post #52

et-al wrote: post #14

On a tangental note, another HN user posted another visualisation a few months back which I quite enjoyed: Why do buses bunch? : http://setosa.io/bus/

Indeed. You can do all sorts of complicated analysis of where, when, and how frequently buses bunch. But the explanation is very simple - like magnets, buses attract each other, in a positive feedback loop. As long as the waiting time at each bus stop depends on the number of passengers that have to get on and off, then buses will always bunch. This is caused by the bus schedule being tight, so the bus has to keep on…

Milwaukee does this, you get on the bus by when an app says it's gonna arrive around there. They also put express buses[1] on the busy routes which don't make the exact same stops. Two ways to split the difference on bunching I guess.

If you check out their site[2] you can click on the Route Map button and see the buses run in real time.

[1] https://urbanmilwaukee.com/2014/12/03/eyes-on-milwaukee-new-...

[2] https://www.ridemcts.com/routes-schedules/greenline

Re: Pittsburgh Bus Bunching (2016)

#64

Post by rident » Wed, Jul 25, 2018, 3:22 AM UTC

et-al wrote: post #14

On a tangental note, another HN user posted another visualisation a few months back which I quite enjoyed: Why do buses bunch? : http://setosa.io/bus/

Buses can also pass each other or not stop at every stop. If two of the same line's buses hit a stop at once, maybe the second rolls on by to the next stop unless they have passengers to drop off? The example is a little too simplistic but does illustrate how rapidly the issue can appear.