paradoxes of randomness

John Kelsey kelsey.j at ix.netcom.com
Fri Aug 22 22:34:12 PDT 2003


At 08:45 AM 8/19/03 -0700, Tim May wrote:
...
>(I strongly urge you to actually do this experiment. Really. These are the 
>experiments which teach probability theory. No amount of book learning 
>substitutes.)

Yep.  I've often thought that one benefit to playing RPGs when I was 
younger was directly observing lots and lots of rolls of various kinds of 
dice.  That gives you an intuition for how unlikely things can happen 
sometimes, for the difference between "very unlikely" and "impossible," etc.

>So the coin has been tossed twice in this particular experiment. There is 
>now the possibility for equal numbers of heads and tails....but for the 
>second coin toss to give the opposite result of the first toss, "every 
>time, to balance the outcomes," the coin or the wind currents would have 
>to "conspire" to make the outcome the opposite of what the first toss 
>gave. (This is so absurd as to be not worth discussing, except that I know 
>of no other way to convince you that your theory that equal numbers of 
>heads and tails must be seen cannot be true in any particular experiment. 
>The more mathematical way of saying this is that the "outcomes are 
>independent." The result of one coin toss does not affect the next one, 
>which may take place far away, in another room, and so on.)

In fact, I believe this is the trick that makes it very easy to distinguish 
between sequences of coin flips that really happen, and ones that are made 
up by a human.  The human tends to try to make things even out over time.

>--Tim May

--John Kelsey, kelsey.j at ix.netcom.com
PGP: FA48 3237 9AD5 30AC EEDD  BBC8 2A80 6948 4CAA F259





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