I think your denominator in your original equation is missing a second term. That is why you get a non-probability for your answer. See here: http://foxholeatheism.com/wp-content/uploads/2011/12/Bayes.jpg
I think your denominator in your original equation is missing a second term. That is why you get a non-probability for your answer. See here: http://foxholeatheism.com/wp-content/uploads/2011/12/Bayes.jpg