Question

Dear Expert Could you please answer below question? A laboratory blood test is 95 percent effective...

Dear Expert

Could you please answer below question?

A laboratory blood test is 95 percent effective in detecting a certain disease when it is, in fact, present. However, the test also yields a “false positive” result for 1 percent of the healthy persons tested. (That is, if a healthy person is tested, then, with probability .01, the test result will imply that he or she has the disease.) If .5 percent of the population actually has the disease, what is the probability that a person has the disease given that the test result is positive?

Homework Answers

Answer #1

Let us denote the events

A : a randomly selected person has the disease

B : a randomly selected person tested positive

Given

Now,

The probability that a person has the disease given that the test result is positive

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