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                            The mean of the sum of squares (MS) is the sum of squares divided by

                     their respective degrees of freedom. The calculation of each sum of squares with
                     its mean (MS) is formulated as follows



                                                    2
                                              2
                          SS(Total)    =  Y j – nY
                                       =  Y j –  (  Y j )  / n
                                              2
                                                        2
                          MS(Total)   = SS(Total)/ n-1


                                                        2
                                         ˆ 2
                          SS(Reg)      = β   (Xj -  X )
                                          1
                                         ˆ 2
                                       = β   [  X i  -  (  X i )  / n ]                           ( R9 )
                                                    2
                                                              2
                                          1
                          MS(Reg)   = SS(Reg)/ p-1

                          SS(Res)      = SS(Total) – SS(Reg)

                          MS(Res)      = SS(Res)/n-p



                            The  results  of  variance  analysis  is  presented  through  the  analysis  of
                     variance table. a value of F is also listed in the table analysis of variance. This is

                     for testing purposes by using the approach of distribution F.



                      Table  5.1     The analysis of variance

                       Source of    Sum of      Degrees of    Mean Squares
                       variation    squares      Freedom           ( MS )             F
                                      (SS )        ( Df )
                      Regression  SS(Reg)      p-1            MS(Reg)              MS (Re  ) g
                                                                               F =
                      Residual     SS(Res)     n-p            MS(Res)              MS (Re  ) s

                      Total        SS(Total)  n-1


                          In partitioning the total sum of squares, SS (Reg) represents the sum of the

                     squares that can be explained or controlled, and SS (Res) represents the sum of

                                                                          2
                                                                                         2
                     squares  unexplained.  MS(Reg)  estimate     +   1     (Xj  -  X ) ,  and  MS(Res)
                                                                   2


                                         ~~* CHAPTER 5   LINEAR REGRESSION MODEL *~~
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