Page 189 - Special Topic Session (STS) - Volume 3
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STS539 Muhammad Abid et al.
            3.  Result
            Table 1 The average run length profiles of the existing charts.
                                 = 10                             = 12
               1
                   EWMA NS   EWMA NAS   CUSUM NS   MEC NAS   EWMA NS   EWMA NAS   CUSUM NS   MEC NAS
             0.05   4.19     3.44     2.71     2.23    4.01     3.10     2.36     2.11
             0.15   5.17     4.44     3.94     3.21    4.56     4.05     3.60     2.90
             0.25   7.02     6.29     6.01     4.93    6.26     5.73     5.48     4.36
              0.3   8.87     8.08     7.90     6.69    7.92     7.33     7.15     5.80
             0.35   12.35    11.37    11.26   10.40    10.88    10.20    10.13    9.00
              0.4   21.39    19.10    19.12   22.79    18.65    16.92    16.93   18.46
             0.45   64.55    51.47    52.54   88.58    58.13    45.29    45.50   74.48
              0.5   369.20   369.53   372.33   369.96   372.00   371.25   370.00   369.56
             0.55   64.30    51.37    52.56   86.69    59.07    44.74    44.93   73.73
              0.6   21.33    19.04    19.23   22.54    18.58    17.07    16.91   18.46
             0.65   12.36    11.40    11.23   10.59    10.96    10.29    10.10    8.94
              0.7   8.87     8.11     7.88     6.66    7.91     7.36     7.14     5.80
             0.75   7.05     6.33     6.02     4.93    6.28     5.74     5.47     4.38
             0.85   5.17     4.44     3.93     3.20    4.57     4.04     3.59     2.90
             0.95   4.19     3.44     2.71     2.23    4.01     3.10     2.36     2.10

            Table 2 The average run length profiles of the proposed chart.
             n
                  0.05  0.1  0.15  0.2  0.25  0.3  0.35  0.4  0.45  0.5  0.55  0.6  0.65  0.7  0.75  0.8  0.85  0.9  0.95
             10  ARL  1.17  1.54  2.04  2.64  3.49  4.79  7.53  14.08  42.93  371.75  42.3  14.3  7.49  4.77  3.48  2.64  2.03  1.54  1.17
               SDRL 0.56  0.92  1.18  1.45  1.85  2.67  4.7  9.94  33.31  308.67  32.49  10.33  4.68  2.65  1.87  1.45  1.19  0.92  0.56
               P5  1  1  1   1  1  1  1  3  4   6   4    3   1   1   1   1   1   1   1
               P25  1  1  1  1  3  3  4  6  17  114  17  6   4   3   3   1   1   1   1
               P50  1  1  1  3  3  4  6  12  36  310  36  12  6  4   3   3   1   1   1
               P75  1  3  3  4  5  6  10  19  60  559  60  20  10  6  5  4   3   3   1
               P95  3  3  4  5  7  10  17  34  106  955.05  104  35  16  10  7  5  4  3  3
             12  ARL  1.14  1.45  1.92  2.47  3.18  4.3  6.54  12.34  37.78  369  36.97  12.54  6.53  4.33  3.19  2.47  1.92  1.47  1.13
               SDRL 0.41  0.7  0.96  1.18  1.5  2.22  3.91  8.29  28.61  297.87  27.92  8.45  3.88  2.19  1.47  1.17  0.96  0.72  0.39
               P5  1  1  1   1  1  1  2  3  4   8   4    3   2   1   1   1   1   1   1
               P25  1  1  1  1  2  3  4  6  16  122  16  6   4   3   2   1   1   1   1
               P50  1  1  2  3  3  4  6  11  32  311  31  11  6  4   3   2   2   1   1
               P75  1  2  3  3  4  5  9  17  53  556  51  17  8  6   4   3   3   2   1
               P95  2  3  4  4  6  8  14  29  94  935.05  91  29  14  8  6  4  4  3  2
             15  ARL  1.18  1.51  1.89  2.39  3.06  4.28  6.71  13.3  43.14  370.61  43.43  13.23  6.76  4.31  3.11  2.38  1.9  1.5  1.17
               SDRL 0.39  0.6  0.75  0.94  1.26  1.99  3.65  8.39  34.51  405.49  34.4  8.31  3.65  2.01  1.32  0.93  0.74  0.6  0.38
               P5  1  1  1   1  1  2  2  3  7   20  7    3   2   2   1   1   1   1   1
               P25  1  1  1  2  2  3  4  7  18  110  19  7   4   3   2   2   1   1   1
               P50  1  1  2  2  3  4  6  11  34  248.5  34  11  6  4  3  2   2   1   1
               P75  1  2  2  3  4  5  8  18  58  485  59  17  9  5   4   3   2   2   1
               P95  2  3  3  4  5  8  14  29  111  1086  110  29  14  8  6  4  3  3  2

            4.  Discussion and Conclusion
                The performance comparison between proposed and existing charts are
            done on the basis of a well-known measure the average run length (). We
            compared  the  HWMANAS  with  the  EWMA     NS  ,  EWMA NAS  ,  CUSUM NS   and
            MEC  NAS . It is turned out that the proposed chart outperforms in detecting the
            small and moderate shifts in the process location  than the existing charts (cf.
            Table  1  and  2).  So  we  recommend  the  use  of  the  proposed  chart  for  the




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