## Stats Problem

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• Hi, I m not a statistician, but maybe this will help. Run Prob1 from a command shell. Source code is included. Richard Date: Sat, 09 Feb 2002 06:54:21 -0000
Message 1 of 1 , Feb 9, 2002
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Hi,

I'm not a statistician, but maybe this will help.
Run Prob1 from a command shell. Source code is included.

Richard

Date: Sat, 09 Feb 2002 06:54:21 -0000
From: "pentatonika2000" <
pentatonika@...>
Subject: probability math

for 12 unidentified people, meet those 12 people, and then guess
which was which.
The astrologer didn't make a single correct guess.

That surprised me, because I thought that the chances were greater
than 50% in favor of getting at least one correct guess.

But I think I was wrong.  I began calculating the formula for the
chances of getting at least one correct match given the number of
people being matched.  Here's what I came up with:

Given 1 person, the chances are 1 out of 1.
Given 2 persons, the chances are 1 out of 2.
Given 3 persons, the chances are 4 out of 6.
Given 4 persons, the chances are 6 out of 16.

And that's as far as I figured.
I can't discern a pattern from this data, and it would be quite
laborious to figure out the chances given 5 persons.
Does anything already know what the formula is?
Or does anything see a formula from this data?