crazygringo
a year ago
> an unscripted voice comes over the speakers, informing us that the next available train will be here in five minute... 10 minutes later... Our train slithers its way into Bedford station
The author seems to be missing an (unwritten?) rule of train time estimates.
They are never about when a train is actually expected to arrive. They are always about the minimum possible time until the next train.
They are basically just taking the distance to the next train, and calculating how long it will take to arrive if it goes at normal speed.
The point is not to determine whether you'll get somewhere on time. Trains go slow for all sorts of reasons. Trains provide no guarantees.
The point is to look at your phone and think, if it takes me 4 minutes to get to the station and the train is 6 minutes away, am I guaranteed to make the train? In which case, the answer is yes, because the train will never come earlier than advertisted. You won't miss it. And if the next train isn't for 26 minutes (minimum), then how can I efficiently use that time and not waste time getting to the station early?
This concept is rarely clearly communicated, but it's good to be aware of it.
diggan
a year ago
> They are never about when a train is actually expected to arrive
Maybe I'm way beyond my expertise, but isn't the train schedules when the train will leave, rather than when it arrives? I've arrived early at train stations many times with my train already being there, idling, and then it leaves on the scheduled time.
Except I guess during delays in the UK when they announce when the train arrives?
> the train will never come earlier than advertisted
This part kind of makes your comment sound like it's not about delays but about the schedules, which I feel like are the departure time, not the arrival time of the train.
crazygringo
a year ago
The article is referring to NYC subways which, while they run on a schedule in theory, the schedule is effectively irrelevant except for when it leaves its first station.
It won't speed up to compensate for delays, and it's never going to wait at a station because it's running ahead.
So the countdown clocks don't report scheduled times, they are derived from the train's actual current distance.
Obviously medium- and long-distance rain is different.
diggan
a year ago
> It won't speed up to compensate for delays, and it's never going to wait at a station because it's running ahead.
The first part absolutely makes sense, but the second one I'm not so sure. They don't have any "Hold at station" or whatever it's called to get some even spacing if they're running ahead of schedule? Seems unnecessarily chaotic.
Doesn't that mean sometimes you end up with 2 or 3 trains coming right after each other?
xp84
a year ago
> Doesn't that mean sometimes you end up with 2 or 3 trains coming right after each other?
Kind of -- you definitely can have that happen, but probably never because Train #2 is way ahead of schedule, as it's nearly impossible for any American mass transit system's best case scenario to be any better than "on time". When a parade of trains all at once happens, it's more typical that, if trains are theoretically supposed to stop here at 11:10, 11:20, 11:30, and so on, train #1 would be arriving 29 minutes late at 11:39, followed by Train #2 22 minutes late at 11:42, and Train #3 running 14 minutes late at 11:44. For instance, due to "police activity" or worse, when someone dies by suicide on the tracks (pretty sure those delays are much longer than the above example in that case).
jermaustin1
a year ago
Only slightly sarcastic: In the history of the subway, has it ever been early?
karmakaze
a year ago
Except in Japan. Googled "japan train schedule accuracy"
> The average delay for a Shinkansen train is around 20 seconds. For other trains operated by other railway companies, the average delay is around 50 seconds. In both cases, the average delay is less than a minute. But these average figures need to be tempered with the occasional incident.
And quite the opposite for charter vacation flights which can leave hours earlier than the stated departure time.
bryanlarsen
a year ago
Good bus/train statistics acknowledge that early trains are far worse than late ones. If a bus on a 30 minute schedule arrives early, it's effectively 30 minutes late because anybody arriving at the stop on time will miss the bus.