i. If the coefficient of correlation is 0.80, what is the coefficient of determination? ii. What is a measure of the scatter of observed values around the regression line called?
iii. If the correlation between sales and advertising is + 0.6, what percent of the variation in sales can be attributed to advertising?
A) 0.4; standard deviation; 0.3.
B) 0.64; standard error of the estimate; 36%.
C) 0.64; standard error of the estimate; 60%.
D) 0.08; variation; 36%.
E) 0.4; standard error of the estimate; 60%.

Question

Quizplus · Accepted Answer

i. The coefficient of determination (R-squared) is equal to the square of the coefficient of correlation. Therefore, in this case, R-squared = 0.8^2 = 0.64.
ii. The measure of the scatter of observed values around the regression line is called the standard error of the estimate.
iii. The square of the correlation coefficient represents the proportion or percentage of variation in one variable that can be explained by its relationship with the other variable. Therefore, in this case, 0.6^2 = 0.36, which represents 36% of the variation in sales that can be attributed to advertising.

Therefore, the answer is B (0.64; standard error of the estimate; 36%).

I If the Coefficient of Correlation Is 0