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Re: Probabilities
Posted:
Mar 13, 2007 11:56 AM


Anonymous wrote:
> I've got ... BABAAAAAABAAABBAAAAAABA > > I would like to calculate the conditional > probability P(BA).
> If I use a logical thought,
Excellent  someone who is thinking about what's actually happening, and not just blindly using a formula.
> ... if I use the formula > P(BA) = P(B inter A)/P(A)
> I get: > P(B inter A) = 4 / (231) > and P(A) = 17/23 then:
Should you really be using all 23 possible places for the "A"?
> P(BA) = 4/22 * 23/17 = 0.25 > > So I would like to know why the "logical thought" > is wrong and if the result is right with the formula.
You need to worry about the edge cases.



