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Conditional Probability Question
Message posted by karin (via 208.4.10.66) on July 12, 2001 at 4:52 PM (ET)
I would first like to find the conditional probability of X given Y. That I can do with the following formula:
P(X=a | Y=b) = P((X=a) AND (Y=b)) / P(Y=b)
This (I think) will give me the probability of an observation falling within a certain range, given the previous observation. However, how do I determine what that previous observation is, so that I may determine what a and b are?
READERS RESPOND:
(In chronological order. Most recent at the bottom.)
Re: Conditional Probability Question
Message posted by JG (via 128.8.23.203) on July 12, 2001 at 8:57 PM (ET)
This is the standard formula for conditional probability and has nothing to do with previous observations.
Re: Conditional Probability Question
Message posted by mathmagician (via 203.87.15.129) on August 21, 2001 at 6:41 AM (ET)
Conditional prob is
Pr(a|b)= Pr(a Intersect b)
-----------------
Pr(b)
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