Page 159 - Quantitative Data Analysis
P. 159

Quantitative Data Analysis
                                              Simply Explained Using SPSS


                                                  2
               amount  of  total  sum  of  squares  (∑y   )  that  can  be  explained  in
               regression model.  It is one the portion of total sum of square.
                                                   2
               Residual sum of square =   SS res=∑ (Y - Y')  = 90.15561
               SS res the amount of variance in a data set that is not defined by the
               regression model. The SS res = 90.15561 is the measurement of error
               remaining between regression function and data set. Residual sum
               of  square  or  ‘unexplained  sum  of  square’  is  again  the  amount  of
                                       2
               total  sum  of  squares  (∑y   )  that  can  be  explained  in  regression
               model.
                       Therefore it can be said defined that:
                                         2
                                                  ̅
                                2
                              ∑y =∑ (Y - Y') + ∑ (Y' -  ) 2
                                2
                       Or     ∑y =SS res+SS reg
                       Or     Total  sum  of  square  =  Sum  of  square  explained  +
               sum of square unexplained

               F  ratio  in the  problem  #1  is  14.9422  with  1  and  18  df  (degree  of
               freedom). For example, the significance level α=0.05, it is found in
               the F table with 1 and 18 df is 4.41. As obtained F is greater than
               tabulated  value,  it  is  concluded  that  the  regression  Y  on  X  is
               statistically significant.



















               The Theory and Applications of Statistical Inferences           143
   154   155   156   157   158   159   160   161   162   163   164