For a medical test, the probability of testing positive for a healthy person is 5%. Based...

For a medical test, the probability of testing positive for a healthy person is 5%. Based on this, can we find the probability of testing positive for an infected person? If yes, explain how; if no, explain why.

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Expert Solution

Here' the answer to the question. please write back in case you've doubts.

Probability of testing positive for an infected person can be found if you know these:

1. Number of people are actually infected , lets say this is x

2. Number of people who are actually infected and have been correctly tested positive. , lets say this is y

So, the probability of testing positive for an infected person is x/y

Now, if you know the the probability of testing postive for a healthy person is 5% , you don't x and y. You can still find out x by subtracting x from total people in the test. But you still don't know y.

Hence, probability of testing positive for an infected person CANNOT be found out

In other words:

You know the you know the Fale Positive (FP) , but using this cannot find out the TP

orchestra answered 1 year ago

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