Relative Likelihood
• Now suppose we don't know the probability of a
stiff neck, but we do know:
– the probability of whiplash P(W) = (1/1000)
– the probability of a stiff neck given whiplash P(S|W) =
0.8
• What is the relative likelihood of meningitis and
whiplash given a stiff neck?
• Write Bayes' Rule for each and write
P(M|S)/P(W|S)