You are interested In the role of exercise in maintaining ca

You are interested In the role of exercise in maintaining cardiac health among young adult women between the ages of 25 and 35. You ask 60 patients to record the number of days they exercise m a month to see whether frequency of exercise correlates with systolic blood pressure. You calculate the Pearson correlation coefficient, r = -0.16, and conduct a test of its significance. You find that the correlation is significant at alpha= .05. Suppose you want to predict the systolic blood pressure based on the number of days of exercise in a month among young women. The coefficient of determination is r^2= indicating that of the variability in the systolic blood pressure can be explained by the relationship between the systolic blood pressure and the number of days of exercise in a month.

Solution

Coefficient of determination = r² where r is the correlation coefficient

Here r = -0.16

Hence coefficient of determination = 0.0256, indicating that 2.56% of the variability in the systolic blood pressured can be explained by the relationship between the systolic blood pressure and the no of days of exercise in a month.