Page 168 - Quantitative Data Analysis
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Quantitative Data Analysis
                                              Simply Explained Using SPSS


               Result Interpretation for Example # 4

               The value 6.8 is the mean of X values which means that on average
               all values has the worth of 6.8. This is the central tendency of the
               summation of all observations divided by number of observations.
               Similarly the mean of Y values is 4.25 that indicate that 4.25 is the
               balancing point for all Y values.

               Sum  of  square  of  x  values  is  73.2  and  y  values  is  35.75;  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.

               Variance indicates the variation of a set of scores from their mean.
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               Here S x  =3.85, it indicates that each score of x is vary 3.85 from its
               mean. Standard deviation (SD) is the measurement of dispersion for
               a set of data from its mean. Here S x=1.96, it means each value of X is
               1.96 away from the mean. Similarly S y=1.37, that indicates that each
               value of Y is dispersed 1.37 from its mean.

               (r xy=0.80) indicates correlation between X and Y.  Since r xy is positive
               and equal to 0.8, it can be inferred that two variables X and Y has

               positive  highly  correlated.  The  regression equation  is  defined
                                  .  Where, 0.5601 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.

                                                         2
                                                       ̅
               Regression sum of square =   SS reg=∑ (Y' -  ) = 22.964. Regression
               sum of square or ‘explained sum of square’ is the amount of total
                                 2
               sum of squares (∑y  ) that can be explained in regression model.  It

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