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Char Count= 0
                         2:57
          August 31, 2006
 JWBK119-10
                                 Monte Carlo Simulation                      147
                               Histogram of NeqSquare
                                3-Parameter Lognormal
                                                                   Loc  −2.410
              90                                                   Scale  0.1301
                                                                   Thresh  0.1340
              80                                                   N     1000
              70
             Frequency  50
              60

              40
              30
              20
              10
               0
                    0.20  0.21  0.22   0.23  0.24  0.25  0.26
                                    NeqSquare

                     Summary for transform NegSquare
                                                          Anderson-Darling Normality Test
                                                            A-Squared  0.36
                                                            P-Value  0.445
                                                            Mean     19.987
                                                            StDev    2.072
                                                            Variance  4.295
                                                            Skewness  0.0767670
                                                            Kurtosis  0.0301912
                                                            N         1000
                                                            Minimum  13.913
                                                            1st Quartile  18.482
                                                            Median   20.012
                14    16    18    20    22   24    26       3rd Quartile  21.373
                                                            Maximum  26.569
                                                          95% Confidence Interval for Mean
                                                            19.858   20.116
                                                         95% Confidence Interval for Median
                           95% Confidence Intervals         19.820   20.161
                                                          95% Confidence Interval for StDev
           Mean                                             1.985    2.167
          Median
               19.8     19.9      20.0     20.1      20.2

      Figure 10.16  Comparison of process capability between Box--Cox with power −2 and three-
      parameter lognormal fit.


        Data set 2 was generated using the three-parameter lognormal distribution with
      location −2.5, scale 0.13, and threshold 0.1. The histogram with the best-fit distribution
      and Box--Cox transformed (with λ =−2) distribution are shown in Figure 10.16. The
      p-valuefromtheAnderson--Darlingnormalitytestis0.445,indicatingwecannotreject
      the claim that the transformed distribution is normal and the Box--Cox transformation
      is successful.
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