Page 158 - Quantitative Data Analysis
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Quantitative Data Analysis
                                              Simply Explained Using SPSS


               Result Interpretation for Example # 3


               The value 4.95 is the mean of X values which means that on average
               all values has the worth of 4.95. This is the central tendency of the
               summation of all observations divided by number of observations.
               Similarly the mean of Y values is 5.50 that indicate that 5.50 is the
               balancing point for all Y values.

               Sum  of  square of x values  is  134.95  and  y values  is  165;  it  is  the
               mathematical approach to determine the dispersion of data points.
               This tells the summation of difference of each raw score from mean
               value. The sum of square x and y is the square of deviation scores
               which is a key calculation in regression analysis.

               Standard deviation (SD) is the measurement of dispersion for a set
               of data from its mean. Here S x=2.66, it means each value of X is 2.66
               away from the mean. Similarly S y=2.9469, that indicates that each
               value of Y is dispersed 2.9469 from its mean.

               (r xy=0.6735)  indicates  correlation  between  X  and  Y.    Since  r xy  in
               Problem #1 is positive and above 0.6, it can be inferred that two
               variables X and Y has positive moderate correlated.
               According  to  data  in  problem  #1,  the  regression  equation  is

               defined                       .    Where,  0.7447  is  the  slop  of
               the regression line. It can be inferred from this equation that when
               x  increases  y  increases.    This  regression  line  shows  positive
               moderate correlation between predictors and criterion variables.
                                                    ̅
               Regression sum of square =   SS reg=∑ (Y' -  ) 2   =74.84031.
               Regression  sum  of  square  or  ‘explained  sum  of  square’  is  the



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