In an extensive study involving thousands of British children, Arden and Plomin (2006) found
significantly higher variance in the intelligence scores for males than for females. Following are
hypothetical data, similar to the results obtained in the study. Note that the scores are not regular IQ
scores but have been standardized so that the entire sample has a mean of M = 10 and a standard
deviation of s = 2.
Female Male
9 8
11 10
10 11
13 12
8 6
9 10
11 14
9 9
a. Calculate the mean and standard deviation for the sample of n = 8 females and for the sample of
n = 8 males.
b. Based on the means and the standard deviation, describe the differences in intelligence scores for
males and females.