posted by [identity profile] cartesiandaemon.livejournal.com at 01:09pm on 19/11/2013
I feel unreasonably glowy to be included in a group with Simon :) You're the one who knows about stats :)

That's what I thought at first, but it seems statistics is full of things like the birthday paradox where it's not _that_ complicated, but "finding the proper name for it on wikipedia" is the only successful strategy to actually finding the solution, which is what someone did.

Addendum: Scratch my previous suggestion, all the formulas in wikipedia are expressed in terms of a sum from 1 to 8 of the time needed to get the N'th coupon, so you ought to be able to just drop the first few terms of the series. And it's short enough you might just be able to calculate a numerical value for 8... (Although the "how many to have a 90% chance of getting all" is a bit more complicated than "expect time to get all")

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