A study finds R2=0.81R^2 = 0.81R2=0.81. Which of the following is a correct interpretation?
The correlation coefficient rrr is 0.90.90.9 or −0.9-0.9−0.9.
The slope of the regression line is 0.810.810.81.
The average residual is 0.190.190.19.
81%81\%81% of the data points lie exactly on the regression line.