Page 205 - Six Sigma Advanced Tools for Black Belts and Master Black Belts
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OTE/SPH
 OTE/SPH
          August 31, 2006
 JWBK119-12
                          Introduction to the Analysis of Categorical Data
        190              2:58  Char Count= 0
                                1     2      3            1000  2000  3000
                                                                          4.5
                       color                                              3.5
                                                                          2.5
                3
                2                   spine

                1
                                                                          30
                                                  width                   25
                                                                          20
              3000
                                                               weight
              2000
              1000
                   2.5  3.5  4.5             20    25     30
        Figure 12.2 Matrix plot to check for multicollinearity due to significant correlations between
        explanatory variables.



        Table 12.12 Logistic regression table for multiple logistic regression model.
                                                                        95% CI of
                                                                        odds ratio
                                                SE           p-  Odds
        Predictors                   Coefficient Coeff.  Z  value ratio Lower Upper
        Constant                     −20.332   7.429 −2.74 0.006

                    Dummy variable
                     combinations
        Color    c 11   c 12   c 13
        3         1      0      0      1.146   1.244   0.92 0.357  3.15  0.27  36.03
        4         0      1      0      0.427   1.440   0.30 0.767  1.53  0.09  25.78
        5         0      0      1    −0.841    1.737 −0.48 0.628  0.43  0.01  12.98

                     Dummy variable
                      combinations
        Spine
        Condition  c 21      c 22

        2          1          0         −0.849  1.413  −0.60  0.548  0.43  0.03  6.83
        3          0          1         −1.893  1.191  −1.69  0.112  0.15  0.01  1.56

        Width                            0.833  0.284  1.15  0.003  2.30  1.32  4.01
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