00:01
For this problem, we are looking at a case of conditional probability.
00:15
So, generally speaking, the probability of event a given event b is equal to the probability of event a and b, divided by the probability of event b.
00:31
In this case, we're not given explicitly what the probabilities for each outcome are, but we'd be able to use the idea of classical probability to find those probabilities.
00:41
So we are looking for the probability of being evaluated positive for depression, given that they were screened, let's see here, or pardon me, evaluated negative for depression, given that they had a positive test screening result.
01:09
The way that we would find this is we'll take the number of individuals in the intersection of those two categories, neg and screen, divided by the total number of individuals in the study, over the total number of individuals with a positive screening result, over the total number of individuals in the study...