A blood test detects a given disease with probability given that the tested person actually has the disease. With probability , the test incorrectly shows the presence of the disease in a disease-free person. Suppose of the population has the disease. What is the probability that the person tested actually has the disease if the test indicates the presence of the disease?
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A blood test detects a given disease with probability 8/10 given that the tested person actually has the disease. With probability 2/10, the test incorrectly shows the presence of the disease in a disease-free person. Suppose 1/10 of the population has the disease. What is the probability that the person tested actually has the disease if the test indicates the presence of the disease? (A) 1 (B) 9/13 (C) 4/13 (D) 7/13
Probability and Bayes' theorem has come up 190 times in 7 exams since 2004.
This question is on Total probability and Bayes' theorem, part of Probability and Bayes' theorem in Statistics.
Reversing a conditional probability and updating beliefs from evidence.
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Question from the DSE 2006 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.