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Bayes' Theorem

  1. Sep 23, 2008 #1
    Dear all,

    Please clarify the following:

    1.) The difference of conditional probability and Bayes' formula.

    2.) Is Bayes' formula a "all weather condition" formula for all conditional probabilities problem?

    Thank you,

  2. jcsd
  3. Sep 25, 2008 #2
    Can anyone please answer to the above question?
  4. Sep 27, 2008 #3
    1) Conditional probability is [tex] \mathbb{P}(A|B):=\frac{\mathbb{P}(A \cap B)}{\mathbb{P}(B)}[/tex].

    Bayes Theorem is used to swap the condition around,
    [tex] \mathbb{P}(A|B):=\frac{\mathbb{P}(B|A) \mathbb{P}(A)}{\mathbb{P}(B)}[/tex]

    2) You can use Bayes formula for any conditional probabilities such that [tex]\mathbb{P}(B)>0[/tex]
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