05-07-2022, 02:01 AM
(05-06-2022, 05:53 PM)jamincan Wrote: Isn't one of the major achievements of the Shinkansen that it's basically always on time? Between humans and computers, one of them figured out how to do scheduling there.
By "scheduling" I meant in the computer science meaning...i.e., finding a schedule which meets a set of constraints, and I meant hard in a computer science meaning as well...there isn't a fast algorithm to solve it.
It is certainly the case for a given context, on a human train scale, we can find a schedule.
I meant humans are not good at it, in that our intuitions do not usually give us a good direction on finding an optimal solution.
But even then, the on time performance of the Shinkansen (or any train really) isn't about finding a schedule, it's about ensuring that all the constraints are correctly identified and either removed (by eliminating sources of delays) or built into the schedule.
As for the Shinkansen specifically and Japanese trains in general, as I think we've probably covered here, schedules are easier and more reliable when they don't need to account for sharing with freight.