How much greater is the shared variance between two variables if the Pearson correlation coefficient between them is -.4 than if it is .2?
A)Half as much
B)Four times as great
C)Two times as great
D)A quarter as much

Question

Quizplus · Accepted Answer

The shared variance between two variables is calculated using the formula: r^2, where r is the Pearson correlation coefficient. When r = -.4, r^2 = .16, and when r = .2, r^2 = .04. The difference between these two values is .16 - .04 = .12. Since .16 is four times greater than .04, the shared variance between two variables is four times as great when the correlation coefficient is -.4 compared to when it is .2. Therefore, the correct answer is B.

How Much Greater Is the Shared Variance Between Two Variables