Correlation

1. What information is provided by the numerical value of the Pearson correlation?

2. For the following scores, compute the Pearson correlation:

X Y

1 1

2 3

4 9

5 5

3 2

3. It is well known that similarity in attitudes, beliefs, and interests plays an important role in interpersonal attraction. Thus, correlations for attitudes between married couples should be strong. Suppose a researcher developed a questionnaire that measures how liberal or conservative one's attitudes are. Low scores indicate that the person has liberal attitudes, whereas high scores indicate conservatism. The following hypothetical data are scores for married couples:

Couple Wife Husband

A 11 14

B 6 7

C 16 15

D 4 7

E 1 3

F 10 9

G 5 9

H 3 8

Compute the Pearson correlation for these data, and determine whether there is a significant correlation between attitudes for husbands and wives. Set alpha at .05, two tails.