0:00
Hello.
00:01
So here in part a, we had to sample a portion of subjects who got a positive result.
00:06
After taking their boosted thing here can be calculated as p1 -hat is x1 over n1, which is 306 divided by 382.
00:21
That's going to be equal to approximately 0 .801.
00:28
And then p hat 2, so p2 hat, is going to be equal to x2 over n2.
00:37
So here that's going to be equal to 321 over 382, which is going to be equal to approximately 0 .84, say 0.
00:49
Okay, so therefore the sample proportions of subjects with positive results is found to be 0 .801 and 0 .840.
01:02
And then for part b, we have our hypotheses can be framed as our null hypothesis.
01:10
It can be that p1 is equal to p2, and then we have our alternative hypothesis is that p1 is not equal to p2.
01:20
So p1 and p2 here are the two proportions of the subjects with positive results.
01:25
So then the pooled proportion estimate p hat is going to be equal to x1 plus x2 divided by n1 plus n2, which is approximately equal to 0 .821.
01:40
And then we get that our standard error is going to be equal here to the square root of p hat times 1 minus p hat and then times 1 over n1 plus 1 over n2.
01:53
And then taking the square root, give us approximately 0 .0277 for our standard error...