Suppose of a town has tuberculosis. A test is positive with probability if a person has TB and if not. Given a positive test, the probability the person actually has TB is
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2 marks, −0.666666666666667StatisticsProbability and Bayes' theoremTotal probability and Bayes' theoremModerateabout 3 min
DSE 2015 Question 49: Probability and Bayes' theorem
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Suppose 0.1% of a town has tuberculosis. A test is positive with probability 0.999 if a person has TB and 0.002 if not. Given a positive test, the probability the person actually has TB is (A) 0.002/0.999 (B) 1/1000 (C) 1/3 (D) 2/3
Probability and Bayes' theorem has come up 190 times in 7 exams since 2004.
What this question tests
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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