A laboratory blood test is 95% effective in detecting a certain disease when it is in fact, present. However, the test also yields a false positive result for 1% of the healthy persons tested. That is, if a healthy person is tested, then, with probability 0.01, the test result will imply that he or she has the disease. If 0.5% of the population actually has the disease, calculate the probability that (a) a randomly selected person will get a positive test result; (b) a person has the disease given that the test result is positive.

A laboratory blood test is 95% effective in detecting a certain disease when it is in fact, present. However, the test also yields a false positive result for 1% of the healthy persons tested. That is, if a healthy person is tested, then, with probability 0.01, the test result will imply that he or she has the disease. If 0.5% of the population actually has the disease, calculate the probability that (a) a randomly selected person will get a positive test result; (b) a person has the disease given that the test result is positive.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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