Page 147 - Quantitative Data Analysis
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Quantitative Data Analysis
                                              Simply Explained Using SPSS


                             Simple Regression Example # 3

               Here are X and Y scores (the second, third, and fourth pairs of
               columns are continuations of the first pair of columns):
                    X      Y      X      Y      X       Y      X       Y
                    2      2      4      4       4      3      9       9
                    2      1      5      7       3      3      10      6
                    1      1      5      6       6      6      9       6
                    1      1      7      7       6      6      4       9
                    3      5      6      8       8     10      4      10

               1.      Means, sum of squares and cross products, standard
                       deviations, and the correlation between X and Y.
               2.      Regression equation of Y on X.
               3.      Regression and residual sum of squares.
               4.      F ratio for the test of significance of the regression of Y on X,
                                                                         2
                       using the sums of squares (i.e., ss reg and ss res) and using r xy.
               5.      Variance of estimate and the standard error of estimate.
               6.      Standard error of the regression coefficient.
               7.      t ratio for the rest of the regression coefficient. What
                       should the square of the t equal? (That is, what statistic
                       calculated above should it equal?)
                       Using the regression equation, calculate the following:
               8.      Each person’s predicted score, Y’, on the basis of the X’s.
               9.      The sum of the predicted scores and their mean.
               10.     The residuals, (Y - Y’); their sum, ∑( Y - Y’), and the sum of
                                                  2
                       the squared residuals, ∑( Y - Y’) .
               11.     Plot the data, the regression line, and the standardized
                       residuals against the predicted scores.
               12.     Provide SAS code and output to answer above problems
               13.     Interpret results




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