Question

Let event Aequalssubject is telling the truth and event Bequalspolygraph test indicates that the subject is lying. Use your own words to translate the notation Upper P (B|A )into a verbal statement.

Answer 1

P( B | A) will actually be the probability of the polygraph test being wrong.

Explanation:

The event A represents the event that the subject is telling the truth.

The event B represents the event when he fails the polygraph test, which is indicative of the fact that he is lying.

The notation P( B | A) describes the probability that the subject fails the polygraph test given that he is actually telling the truth.

So in retrospect P( B | A) will actually be the probability of the polygraph test being wrong.