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A clinical psychologist is interested in the relationship between testosterone level in married males and the quality of their marital relationship. A study is conducted in which the testosterone levels of eight married men are measured. The eight men also fill out a standardized questionnaire assessing quality of marital relationship. The questionnaire scale is 0–25, with higher numbers indicating better relationships. Testosterone scores are in nanomoles/liter of serum. The data are shown below.
Subject Number |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
Relationship Score |
24 |
15 |
15 |
10 |
19 |
11 |
20 |
19 |
Testosterone Level |
12 |
13 |
19 |
25 |
M |
16 |
15 |
21 |
a. Determine the least-squares regression line for predicting relationship score from testosterone level.
b. What percentage of the variance in relationship score is accounted for by the regression equation?
c. Can we conclude that there is a significant relationship between the testosterone level and the relationship score? Use the 5% significance level.
M – your birth month.
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