What can you say aboutSSE, SSR and the utility of the regression equation for making predictions if

a. r2=1?

b.r2=0?

Short Answer

Expert verified

(a) SSR=SST

SSE=0

The regression equation is very useful to determine predictions.

(b)SSE=SST

SSR=0

The regression equation is not useful in making predictions.

Step by step solution

01

Part (a) Step 1: Given Information 

The given equation is:

r2=1

we have to determine SSE, SSR and the utility of the regression equation .

02

Part (a) Step 2: Explanation 

The coefficient of determination is given by r2=SSRSST

It is given that r2=1, this means that SSR and SST will be equal to each other. The relationship between SST, SSR and SSE is given by

SST=SSR+SSE

Therefore, SSE=0. As it can be seen that the coefficient of determination is equal to 1, therefore, the regression equation is very useful in making the predictions.

03

Part (b) Step 1: Given Information 

The given equation is:

r2=0

we have to determine SSE, SSR and the utility of the regression equation.

04

Part (b) Step 2: Explanation 

The coefficient of determination is given by r2=SSRSST

It is given that r2=0; this means that SSR=0because SST cannot be equal to zero. The relationship between SST, SSR and SSE is given by

SST=SSR+SSE

Therefore, SST = SSE.. As it can be seen that the coefficient of determination is equal to 0, therefore, the regression equation is not useful in making the predictions.

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