(New page: '''The Problem:''' There is a new test that will test for the HIV virus, but we are not sure of whether this test's results are usually correct or not. We are given the following informati...) |
|||
| Line 7: | Line 7: | ||
| − | We are also given that only <math>0.5%\!</math> | + | We are also given that only <math>0.5%\!</math> of the population has the HIV virus. The rest do not. |
Revision as of 06:03, 5 October 2008
The Problem: There is a new test that will test for the HIV virus, but we are not sure of whether this test's results are usually correct or not. We are given the following information:
$ P (+ | HIV) = 0.9, P (- | HIV) = 0.1\! $
$ P (+ | no HIV) = 0.1, P (- | no HIV) = 0.9\! $
We are also given that only $ 0.5%\! $ of the population has the HIV virus. The rest do not.
Are the results usually correct, and what can you tell from the results?
The Solution:
