Question

Question 8(Multiple Choice Worth 5 points) (02.05 MC) Regressions were performed on measurements, x and y, taken on 8 subjects. Regression 1 produced y = 57.1024 + 17.331x and had the residual plot: 30 25 20 15 10 . 5 0 0 2 4 6 8 10 12 14 16 -5 -10 -15 -20 Regression 2 produced vý = 0.158283 +0.98559 x and had the residual plot: 0.15 0.1 0.05 0 0 2 4 6 8 10 12 14 16 -0.05 -0.1 -0.15

Answer 1

## We have given two regression model and it residual plot :

for model 1 :

Estimated regression equation :

ŷ = 57.1024 + ( 17 .331 * x ) and

Residual plot :

from plot we can say that points are scatter in some pattern that is nonlinear pattern ,

hence we can say there is nonlinearity , we should to change in the structural form of the model . we can use

transformation of variables and check again constant variance occur or not .

## For model 2 :

Estimated regression equation :  

√ ŷ = 0.158283 + 0.98559 *x

Residual plot :

from plot we can say that points are scatter everywhere there is no pattern of it .

hence we can say there is linearity , and no need to change form of the model .

no need to do transformation of the variables .

## Which statement is best supported by the evidence ?

Answer : correct statements is :

Regression 2 is a better fit as there is a linear relationship between x and y .