In: Statistics and Probability
Problem (simple linear regression). McDonald’s Corporation reported total revenues (X) and net profits (Y) from 1998 to 2005. Using 2-var statistics, we get:
x-average=15.86; standard deviation of X =2.82; y-average=1.795, standard deviation of Y=0.5278; n=8 (from 1998 to 2005). Sum of squared X=2067.50, sum of squared Y=27.73, and sum of the product of X and Y =233.28.
The least-square regression is
Y (net profit) =0.2107+0.0999X (total revenue), with ESS=1.3965, and standard error of estimate (Sy,x)=0.4824.