Suppose you have a test X to diagnose influenza.
Test X is 90% positive when the patient is flu, and Test X is 90% negative when the patient is not flu.
Now, suppose people in the world have flu with a 10% chance. What is the probability that when a patient is positive for test X, the patient is actually flu? _____%
is this using bayes such as p(f|positive)= (1/10 * 90/100) / (0.1*0.9 + 0.9*0.9) =0.1 am i right?