i. If the coefficient of correlation is 0.70, what is the coefficient of determination? ii. If the value of r is -0.88, what does this indicate about the dependent variable as the independent variable increases?
iii. If the correlation between sales and advertising is -0.7, what percent of the variation in sales can be attributed to advertising?
A) 0.49; it decreases; 0.49.
B) 0.49; it decreases;0.7.
C) 0.49; it increases;0.49.
D) 0.8367; it decreases;0.7.
E) 0.8367; it increases;0.8367.

Question

Quizplus · Accepted Answer

The coefficient of determination is found by squaring the coefficient of correlation, so $0.70^2 = 0.49$. A negative correlation (r = -0.88) indicates that as one variable increases, the other decreases. The coefficient of determination (r^2) for a correlation of -0.7 is $0.7^2 = 0.49$, meaning 49% of the variation in sales can be attributed to advertising.

I If the Coefficient of Correlation Is 0