Page 182 - Quantitative Data Analysis
P. 182

Quantitative Data Analysis
                                              Simply Explained Using SPSS


               indicates correlation between x 1 and x 2.  Since r 12 is positive and less
               than  0.2,  it  can  be  concluded  that  x1  and  x2  has a weak  positive
               correlation.  (r y1=0.6735)  indicates  correlation  between  y  and  x 1.
               Since r y1 is positive and greater than 0.5, it can be concluded that y
               and  x 1  has  a  positive  moderate  correlation.  (r y2=0.5320)  indicates
               correlation between y and x 2.  Since r y2 is positive and greater than
               0.5,  it  can  be  concluded  that  y  and  x 2  has  a  positive  moderate
               correlation. Sum of square regression (SS reg=106.661) is analysis of
               variance, it is also known as sum of square explained. On the other
               hand  sum  of  square  residuals  (SS res=58.3398)  is  the  difference
               between the total sum of square and sum of square explained. In
                                                  2
               this problem, the overall correlation R y. 12 =0.6464, which indicates
               that the overall variables have a positive correlation.  F ratio in the
               problem  #1  is  15.54  with  1  and  17  df  (degree  of  freedom).  For
               example, the significance level α=0.05, it is found in the F table with
               1 and 17 df is 4.45. As obtained F is greater than tabulated value, it
               is concluded that the regression Y on X is statistically significant. The
               calculated F(1,17) = 9.27 while the critical value of F(1,17) is 4.45, so
               F for the increment of X 2 over X 1 is significant. The calculated F(1,17)
               =  17.47  while  the  critical  value  of  F(1,17)  is  4.45,  so  F  for  the
               increment of X 1 over X 2 is quite significant.





















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