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The waiting time paradox: why is my bus always late? (2018)

(jakevdp.github.io)
219 points skadamat | 5 comments | 20 Aug 24 13:55 UTC | HN request time: 0.001s | source
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rjmunro ◴[20 Aug 24 17:11 UTC] No.41301868[source]▶
There's another thing that happens with busses that makes it worse.

The further behind the previous bus a bus is, the more people will arrive at the bus stop. The more people there are at the stop, the longer the bus has to spend picking them all up and selling them tickets etc. Therefore the delayed bus will tend to experience more delay. The bus behind them will have less people to pick up, so it will spend a shorter time at stops and tend to catch up with the first bus, so the two busses are dragged towards each other.

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mitthrowaway2 ◴[20 Aug 24 18:05 UTC] No.41302390[source]▶
That bus with more riders on board also has a higher probability of needing to stop to let people off at each location as well, slowing it down even further!
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Gravityloss ◴[20 Aug 24 19:05 UTC] No.41302948[source]▶
Robotic buses could be made smaller than driver buses since the cost of driver doesn't need to be amortized as many passengers as possible. Then you could implement optional stop skipping. At the end of the spectrum you have Uber X ie taxi with ride sharing.
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1. stouset ◴[20 Aug 24 19:52 UTC] No.41303399[source]▶
Buses already do this.

If nobody is waiting and nobody asks to get off they don’t stop. If nobody asks to get off and there’s a second bus right behind, drivers skip the stop.

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2. taeric ◴[20 Aug 24 23:10 UTC] No.41305025[source]▶
It amuses me how many people don't know how busses work on that front. I'm assuming most people have more of a train mentality when it comes to this?
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3. lidavidm ◴[21 Aug 24 01:12 UTC] No.41305784[source]▶
I'd guess most people here don't actually take buses on a regular basis. (Or ever. Or any public transit at all.)
4. Gravityloss ◴[21 Aug 24 09:08 UTC] No.41308325[source]▶
Yes of course. But it's not so useful since the buses are so big and they arrive so infrequently. With robobuses you could have smaller more frequent arrivals and then have higher probability of skipping. If the robobus understands the bus stop person's gestures that are they trying to stop it or not...
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5. stouset ◴[22 Aug 24 20:06 UTC] No.41323938[source]▶
The cost of a human operator is not even remotely close to as important a factor as you think it is.

SF recently acquired 33 new buses for $1.7 million apiece. Throw in maintenance and fuel costs and it’s easy to see that amortizing over a driver making $40/hr plus benefits is just not that big a deal, especially if you’re now adding a suite of sensors, electronics, and computing hardware.