`1. For the following scores, find the (a) mean, (b) median, (c) sum of squared deviations, (d) variance, and (e) standard deviation.

27,

23,

35,

26,

29,

29,

28,

32,

30

2. For the following scores, find the (a) mean, (b) median, (c) sum of squared deviations, (d) variance, and (e) standard deviation.

4.59,

2.46,

4.08,

5.86

3.A researcher is studying the amygdala (a part of the brain involved in emotion). Six participants in a particular fMRI (brain scan) study are measured for the increase in activation of their amygdala while they are viewing pictures of violent scenes. Find the a) mean and

b) standard deviation for this sample of activation increases.

The activation increases are

0.27,

0.35,

0.39,

0.31,

0.29, and

0.51.

4. A developmental psychologist studies the number of words that seven infants have learned at a particular age. Figure the (a) mean, (b) median, and (c) standard deviation for the number of words learned by these seven infants. (d) Explain what the results mean to a person who has never had a course in statistics.

The numbers are

11,

12,

7,

2,

5,

45, and

19.