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                   2.  Data on the measurements results of several organs of the body are presented

                     in Table 5.18. With linear regression model, want to investigate the influence of
                     a group of independent variables, namely the size of the lungs (X1), heart (X2),

                     liver (X3), spleen (X4) against Kidney size (Y). In Table 5.19, through the SAS

                     output is presented the matrix ( X’X )  of linear regression model.
                                                            -1

                     a.  Find the estimated regression equation

                     b.  Test  the  significance  of  the  regression  model  by  testing  the  following
                        formulation of the test hypothesis

                       H0 : 1 = 2  = 3  = 4 =0

                       H1 :  j  0 , For the smallest one of the j       j = 1, 2, 3,4

                       Find the sum of squares regression using

                       SS(Reg) = SS( 1  0  ) + SS( 2   0 , 1 )+ SS( 3   0 , 1 , 2 )

                                         + SS( 4   0 , 1 , 2 , 3 )


                     c. Perform partial testing for each regression coefficients, i.e test the following

                       hypotheses.

                       H0 :  j = 0.

                       H1 :  j  0 ,                    j = 1, 2, 3, 4


                     d.  Perform sequential testing on the order of independent variables X1, X2, X3 ,

                        and X4.

                     e.  By  defining  a  general  linear  hypothesis,  test  the  contribution  3  regressors,

                       namely  the  lungs  (X1),  liver  (X3),  and  spleen  (X4),  to  the  sum  of  squares

                       regression, which is testing the hypothesis H0 : 1 = 3 = 4 = 0.

                     f. By defining a general linear hypothesis, test the hypothesis

                        H0: 0 = 0 dan 1 = 3 = 4 = 0.










                                   ~~* CHAPTER 5   THE MULTIPLE LINEAR REGRESSION MODEL *~~
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