
Re: say I flip a coin 100 times...
Posted:
Apr 16, 2005 2:58 PM


HERC777 wrote: > OK lets move on to Q3... > at time 0 there are 0 people flipping coins. > At time 1/2 there is 1 person flipping > coins at t=1/2, t=3/4, t=7/8... > At time 3/4 there is another person flipping > coins at t=3/4, t=7/8, t=15/16.. > At time 7/8 another person joins in flipping coins... > and so on...
This means you will have an infinite number of people flipping an infinite number of times each, if t ever gets to 1.
> > At time t = 1, Herc starts flipping > coins at t=1, t=2, t=3, t=4, t=5... > > How long does Herc flip out for until it is > recognised he is unique > from all of the masses?
Forever, basically. At any given finite time, you have only flipped a finite number of times. But there are infinitely many people flipping before you, and the expected number of them that match you, for a prefixlength equal to thenumberoftimesyouhaveflippedsofar, is ALSO INFINITE. In order to get the number of expected matchessofar down to something finite, you have to determine some finite subset of the flippers that are worth thinking about, at any given time.

