A set of n = 25 pairs of scores (X and Y values)has a Pearson correlation of r = 0.80.How much of the variance for the Y scores is predicted by its relationship with X?
A)0.36 or 36%
B)0.20 or 20%
C)0.80 or 80%
D)0.64 or 64%

Question

Quizplus · Accepted Answer

The formula for calculating the coefficient of determination (r^2) is r^2 = (explained variance)/(total variance). We know that r = 0.80, so r^2 = 0.64. Therefore, 64% of the variance in the Y scores is predicted by the relationship with X. Choice D is the correct answer.

A Set of N = 25 Pairs of Scores (X