Page 391 - Six Sigma Advanced Tools for Black Belts and Master Black Belts
P. 391

OTE/SPH
 OTE/SPH
                         3:8
          August 31, 2006
 JWBK119-24
                              Char Count= 0
        376              Cumulative Sum Charts with Fast Initial Response
        Table 24.1 FIR CUSUM example: initially-out-of-control case; h = 5, k = 0.5 (from Table 5,
                      11
        Lucas and Crosier ).
                                                     CUSUM  +
                                                            i
                                       Tabular                       V-mask
        i                       No FIR           FIR           No FIR          FIR
        0           --            0.0            2.5             0              0
        1          0.8            0.3            2.8             0.8            3.3
        2          1.9            1.7            4.2             2.7            5.2
        3          1.4            2.6           5.1**            4.1            6.6
        4          2.0            4.1           6.6**            6.1            8.6
        5          1.1            4.7           7.2**            7.2            9.7
        6          0.7            4.9           7.4**            7.9           10.4
        7          2.6            7.0*          9.5**           10.5           13.0

        *CUSUM out-of-control signal.
        **FIR CUSUM out-of-control signal.


                       Tabular CUSUM                         V-mask CUSUM
           8                                    12
           6 4                                  10
         Cumulative Sum  2 0                   Cumulative Sum  8 6 4




          −2
          −4                                     2
          −6                                     0
            0       2      4       6       8      0  2   4  6   8  10  12  14  16  18
                         Sample                                Sample

           Figure 24.3  The Tabular and V-mask CUSUM without FIR for the data in Table 24.1.


                     Tabular FIR CUSUM                     V-mask FIR CUSUM
          12                                    14
          10
                                                12
           8
         Cumulative Sum  6 4 2 0               Cumulative Sum  8 6
                                                10


          −2
          −4                                     4 2
          −6                                     0
            0       2      4       6       8      0   2    4   6    8   10  12   14
                         Sample                                Sample

           Figure 24.4 The tabular and V-mask CUSUM without FIR for the data in Table 24.1.
   386   387   388   389   390   391   392   393   394   395   396