Table 6 Comparison of the proposed control chart with CUSUM chart at ARL0 ≈ 370.
From: Adaptive VSS-EWMA control chart for monitoring the process dispersion
Shift | VEWMA | VEWMA | FCUSUM | FCUSUM | FCUSUM | FCUSUM | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
\(\psi\)= 0.10 n1 = 3 and n2 = 6 | \(\psi\)= 0.10 n1 = 5 and n2 = 10 | K = 0.30 n = 3 | K = 0.50 n = 3 | K = 0.30 n = 5 | K = 0.50 n = 5 | |||||||
ARL | SDRL | ARL | SDRL | ARL | SDRL | ARL | SDRL | ARL | SDRL | ARL | SDRL | |
0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 |
0.25 | 2.57 | 0.54 | 1.98 | 0.19 | 5.41 | 0.86 | 4.37 | 0.89 | 3.62 | 0.51 | 2.83 | 0.46 |
0.50 | 4.99 | 1.82 | 3.17 | 0.91 | 10.54 | 2.99 | 9.83 | 3.90 | 6.45 | 1.40 | 5.35 | 1.50 |
0.75 | 17.44 | 10.80 | 9.60 | 4.98 | 34.51 | 21.16 | 52.77 | 44.43 | 17.84 | 7.93 | 20.02 | 12.66 |
0.90 | 103.70 | 96.43 | 54.65 | 47.01 | 177.63 | 163.44 | 258.71 | 251.51 | 90.46 | 76.68 | 141.45 | 133.90 |
1.0 | 369.67 | 366.09 | 370.66 | 363.93 | 370.90 | 362.41 | 370.03 | 368.71 | 37.53 | 364.44 | 370.77 | 368.09 |
1.05 | 187.70 | 181.48 | 136.72 | 132.06 | 230.48 | 217.82 | 237.78 | 230.27 | 176.19 | 166.53 | 197.15 | 191.87 |
1.25 | 18.65 | 14.73 | 10.99 | 7.58 | 32.82 | 23.60 | 34.87 | 29.83 | 19.07 | 11.45 | 18.97 | 14.21 |
1.50 | 7.01 | 4.67 | 4.42 | 2.50 | 13.23 | 7.28 | 11.85 | 8.09 | 8.18 | 3.58 | 6.92 | 3.80 |
2.0 | 3.30 | 1.83 | 2.26 | 1.03 | 6.22 | 2.78 | 5.09 | 2.79 | 4.12 | 1.51 | 3.28 | 1.44 |
3.0 | 1.93 | 0.91 | 1.42 | 0.57 | 3.35 | 1.38 | 2.66 | 1.31 | 2.30 | 0.79 | 1.82 | 0.74 |
