00:01
We're looking at some aptitude test scores, but because people took different versions of the test, we need some way to compare them.
00:08
So let's go through these people.
00:11
We have cade.
00:12
He got a score of 76 .9, and his version had a mean, mu, of 62 .9, and a standard deviation of 7.
00:26
Brittany scores 325 .4.
00:29
Her version of the test had a mean of 288, a standard deviation of 17, terra scored 7 .84, her test had a mean of 7 .4 and a standard deviation of 0 .4.
00:50
So, who performed best on the aptitude test? so i'm going to compare the z scores here.
00:58
A z score tells you how many standard deviations away from the mean a value is.
01:04
To calculate it, you take your value, subtract the mean, divide by the standard deviation...