Question

One percent of all individuals in a certain population are carriers of a particular disease. A

diagnostic test for this disease has a 93% detection rate for carriers and a 2% false positive rate. Suppose that an individual is tested. What is the specificity of the test? What is the probability that an individual who tests negative does not carry the disease?

Answer #1

Solution:

Given:

P(Disease)=0.01

P(Positive | Disease)=0.93

P(Positive | Not disease)=0.02

Therefore, first we need to find Specificity.

Formula:

Now we have to find the probability that an individual who tests negative does not carry the disease.

That is, P(Not Disease | Negative)=...?

Before that, first we need to find P(Negative).

Now,

Done

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