Let a probability of disease is 1 in 10,000 and the test accuracy of the disease is 99 %, that is, the…
The probability is approximately 0.0098. By Bayes' rule, P(A | B) = 0.99(0.0001)/[0.99(0.0001) + 0.01(0.9999)] = 0.000099/0.010098 = 0.0098039. Because the disease is rare,…
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Let a probability of disease is 1 in 10,000 and the test accuracy of the disease is 99 %, that is, the test is positive for 99% of people who have the disease and negative for 99% of people who do not. Let event A is the event you have this disease, and event B is the event that you test positive. Given test is positive what is the probability that disease is actually present?
Answer and explanation
Correct answer D
The probability is approximately 0.0098. By Bayes' rule, P(A | B) = 0.99(0.0001)/[0.99(0.0001) + 0.01(0.9999)] = 0.000099/0.010098 = 0.0098039. Because the disease is rare, the false positives among the many healthy people far outnumber the true positives, so a positive result still leaves the disease unlikely.
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Telangana SET (TG SET)