Table 2 Run length profile of Bayesian Max-EWMA control chart as a result of a shift in Weibull parameters W(1, 1.5) with \(\gamma\)=0.25 and considering subgroup size as 3, 5, and 7.
From: Memory type Max-EWMA control chart for the Weibull process under the Bayesian theory
\(\alpha\) | n | Shape parameter = \(\lambda\) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0.50 | 1.00 | 1.25 | 1.50 | 1.75 | 2.00 | 2.25 | 2.50 | 2.75 | 3.00 | 4.00 | 5.00 | ||
ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ||
0.25 | (µ, σ) | (−1.51, 2.04) | (−1.49, 0.89) | (−1.45, 0.72) | (−1.42, 0.61) | (−1.40, 0.53) | (−1.38, 0.47) | (−1.36, 0.42) | (−1.35, 0.38) | (−1.33, 0.35) | (−1.32, 0.32) | (−1.29, 0.25) | (−1.28, 0.20) |
3 | 2.46 (1.17) | 2.74 (0.79) | 2.79 (0.71) | 2.84 (0.65) | 2.87 (0.58) | 2.93 (0.54) | 2.98 (0.53) | 2.99 (0.43) | 3.03 (0.39) | 3.05 (0.37) | 3.05 (0.31) | 3.01 (0.27) | |
5 | 1.87 (0.77) | 2.10 (0.46) | 2.12 (0.39) | 2.12 (0.34) | 2.12 (0.33) | 2.11 (0.32) | 2.12 (0.33) | 2.11 (0.32) | 2.12 (0.33) | 2.12 (0.32) | 2.09 (0.29) | 2.03 (0.19) | |
7 | 1.60 (0.62) | 1.84 (0.42) | 1.90 (0.33) | 1.95 (0.25) | 1.97 (0.17) | 1.99 (0.10) | 1.99 (0.07) | 1.99 (0.04) | 1.99 (0.03) | 1.99 (0.02) | 1.99 (0.05) | 1.98 (0.10) | |
0.50 | (µ, σ) | (−0.68, 3.16) | (−0.87, 1.11) | (−0.84, 0.90) | (−0.81, 0.76) | (−0.78, 0.66) | (−0.76, 0.58) | (−0.74, 0.53) | (−0, 72, 0.48) | (−0.71, 0.44) | (−0.70, 0.40) | (−0.66, 0.31) | (−0.64, 0.25) |
3 | 1.96 (1.00) | 5.74 (2.99) | 6.22 (2.92) | 6.78 (3.04) | 7.28 (3.18) | 7.58 (3.02) | 7.89 (3.09) | 7.92 (3.01) | 7.67 (2.80) | 7.19 (2.54) | 5.61 (1.82) | 4.52 (1.22) | |
5 | 1.48 (0.63) | 3.97 (1.66) | 4.15 (1.55) | 4.38 (1.69) | 4.52 (1.39) | 4.57 (1.28) | 4.54 (1.19) | 4.44 (1.10) | 4.18 (1.00) | 3.85 (0.91) | 3.09 (0.65) | 2.65 (0.53) | |
7 | 1.25 (0.46) | 3.18 (1.19) | 3.29 (1.07) | 3.42 (0.99) | 3.54 (0.93) | 3.52 (0.82) | 3.49 (0.75) | 3.37 (0.71) | 3.16 (0.66) | 2.93 (0.60) | 2.36 (0.49) | 2.06 (0.26) | |
0.75 | (µ, σ) | (0.01, 4.18) | (−0.42, 1.30) | (−0.39, 1.05) | (−0.36, 0.88) | (−0.34, 0.77) | (−0.32, 0.68) | (−0.29, 0.61) | (−0.28, 0.56) | (−0.26, 0.51) | (−0.25, 0.47) | (−0.21, 0.37) | (−0.18, 0.30) |
3 | 1.51 (0.71) | 13.13 (9.90) | 26.32 (22.10) | 45.30 (39.60) | 59.18 (53.36) | 50.09 (43.58) | 32.10 (26.23) | 22.55 (17.06) | 15.92 (10.83) | 12.31 (7.34) | 7.35 (3.11) | 5.45 (1.79) | |
5 | 1.17 (0.40) | 8.49 (5.55) | 15.71 (11.85) | 22.41 (17.22) | 23.19 (17.42) | 16.22 (10.93) | 10.61 (5.99) | 7.91 (3.78) | 6.18 (2.50) | 5.22 (1.83) | 3.67 (0.91) | 3.01 (0.62) | |
1.07 (0.26) | 6.49 (3.69) | 11.26 (7.79) | 14.61 (9.95) | 13.90 (8.94) | 9.54 (5.13) | 6.59 (2.87) | 4.23 (1.32) | 4.25 (1.31) | 3.69 (0.99) | 2.75 (0.60) | 2.29 (0.46) | ||
1.0 | (µ, σ) | (0.61, 5.00) | (−0.05, 1.47) | (−0.03, 1.18) | (0.00, 1.00) | (0.03, 0.87) | (0.05, 0.77) | (0.07, 0.69) | (0.09, 0.63) | (0.11, 0.58) | (0.12, 0.54) | (0.16, 0.41) | (0.19, 0.34) |
3 | 1.31 (0.55) | 12.51 (9.61) | 61.46 (57.13) | 370.87 (367.43) | 348.36 (344.16) | 142.09 (138.02) | 73.03 (66.94) | 39.54 (33.40) | 25.911 (20.49) | 19.30 (13.62) | 8.89 (4.45) | 6.42 (2.41) | |
5 | 1.09 (0.29) | 7.58 (4.94) | 39.57 (35.42) | 370.89 (365.34) | 173.67 (170.29) | 47.57 (42.11) | 20.20 (14.96) | 12.35 (7.48) | 8.89 (4.60) | 7.14 (3.19) | 4.17 (1.20) | 3.36 (0.77) | |
10 | 1.02 (0.15) | 5.56 (3.14) | 28.26 (24.46) | 370.87 (364.22) | 105.35 (100.46) | 25.09 (19.74) | 11.31 (6.90) | 7.48 (3.61) | 5.68 (2.26) | 1.94 (0.22) | 3.06 (0.71) | 2.57 (0.55) | |
1.25 | (µ, σ) | (1.17, 5.69) | (0.28, 1.65) | (0.29, 1.31) | (0.32, 1.11) | (0.35, 0.96) | (0.37, 0.86) | (0.39, 0.77) | (0.41, 0.70) | (0.43, 0.64) | (0.45, 0.60) | (0.49, 0.46) | (0.52, 0.38) |
3 | 1.21 (0.45) | 7.12 (4.76) | 17.29 (13.83) | 31.77 (27.64) | 40.80 (35.39) | 43.02 (37.31) | 22.66 (16.88) | 36.07 (30.02) | 28.31 (22.21) | 23.14 (16.89) | 11.16 (6.11) | 7.56 (3.23) | |
5 | 1.05 (0.21) | 4.61 (2.54) | 10.81 (7.48) | 20.05 (16.16) | 21.90 (17.12) | 21.10 (15.69) | 17.50 (12.17) | 13.62 (8.24) | 10.41 (5.50) | 8.67 (4.10) | 4.97 (1.61) | 3.09 (0.65) | |
10 | 1.01 (0.10) | 3.56 (1.70) | 8.01 (5.09) | 14.35 (10.79) | 15.09 (10.87) | 13.52 (8.89) | 10.94 (6.17) | 8.55 (4.07) | 6.74 (2.70) | 5.71 (2.06) | 3.56 (0.92) | 2.82 (0.62) | |
\(\alpha\) | N | Shape parameter = \(\lambda\) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0.50 | 1.00 | 1.25 | 1.50 | 1.75 | 2.00 | 2.25 | 2.50 | 2.75 | 3.00 | 4.00 | 5.00 | ||
ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ARL (SDRL) | ||
1.50 | (µ, σ) | (1.67, 6.26) | (0.58, 1.86) | (0.58, 1.44) | (0.61, 1.21) | (0.64, 1.05) | (0.66, 0.94) | (0.68, 0.84) | (0.70, 0.77) | (0.72, 0.71) | (0.74, 0.65) | (0.79, 0.51) | (0.82, 0.41) |
3 | 1.16 (0.39) | 4.40 (2.52) | 7.48 (4.96) | 9.34 (6.31) | 9.79 (6.21) | 9.76 (5.90) | 9.46 (5.33) | 9.04 (4.81) | 8.52 (4.23) | 8.07 (3.67) | 6.87 (2.38) | 5.98 (1.69) | |
5 | 1.03 ( 0.18) | 3.10 (1.47) | 5.16 (2.85) | 6.29 (3.53) | 6.20 (3.27) | 6.10 (2.96) | 5.75 (2.48) | 5.46 (2.16) | 5.22 (1.86) | 4.88 (1.57) | 3.62 (0.78) | 3.64 (0.73) | |
7 | 1.00 (0.07) | 2.51 (1.05) | 4.10 (1.96) | 4.97 (2.47) | 4.82 (2.17) | 4.60 (1.92) | 4.41 (1.62) | 4.17 (1.35) | 3.95 (1.18) | 3.75 (1.00) | 3.24 (0.64) | 2.85 (0.51) | |
2.00 | (µ, σ) | (2.57, 7.16) | (1.16, 2.43) | (1.11, 1.70) | (1.13, 1.41) | (1.15, 1.23) | (1.18, 1.09) | (1.20, 0.98) | (1.23, 0.89) | (1.25, 0.82) | (1.26, 0.76) | (1.32, 0.59) | (1.36, 0.48) |
3 | 1.10 (0.32) | 2.42 (1.22) | 3.49 (1.76) | 3.82 (1.88) | 2.99 (1.14) | 3.70 (1.51) | 3.60 (1.32) | 3.47 (1.16) | 3.40 (1.06) | 3.33 (0.97) | 3.11 (0.70) | 2.98 (0.54) | |
5 | 1.01 (0.13) | 1.80 (0.77) | 2.59 (1.09) | 2.84 (1.16) | 2.81 (1.03) | 2.71 (0.90) | 2.64 (0.80) | 2.55 (0.70) | 2.49 (0.63) | 2.58 (0.64) | 2.27 (0.46) | 2.15 (0.36) | |
7 | 1.00 (0.04) | 1.52 (0.60) | 2.19 (0.83) | 2.36 (0.84) | 2.33 (0.76) | 2.27 (0.66) | 2.21 (0.58) | 2.14 (0.49) | 2.11 (0.44) | 2.09 (0.39) | 2.01 (0.21) | 1.99 (0.11) | |
2.50 | (µ, σ) | (3.33, 7.82) | (1.74, 3.18) | (1.59, 2.05) | (1.59, 1.61) | (1.62, 1.39) | (1.64, 1.23) | (1.67, 1.11) | (1.69, 1.01) | (1.72, 0.93) | (1.73, 0.86) | (1.80, 0.67) | (1.84, 0.55) |
3 | 1.07 (0.26) | 1.70 ( 0.81) | 2.34 (1.09) | 2.59 (1.10) | 2.56 (0.99) | 2.51 (0.87) | 2.46 (0.77) | 2.41 (0.69) | 2.34 (0.61) | 2.32 (0.56) | 2.18 (0.41) | 2.10 ( 0.31) | |
5 | 1.00 (0.08) | 1.30 (0.50) | 1.82 (0.73) | 1.97 (0.73) | 1.96 (0.60) | 1.95 (0.59) | 1.91 (0.53) | 1.89 (0.48) | 1.87 (0.43) | 1.86 (0.41) | 1.85 (0.35) | 1.86 (0.34) | |
7 | 1.00 (0.02) | 1.14 (0.36) | 1.54 (0.59) | 1.68 (0.61) | 1.90 (0.69) | 1.65 (0.53) | 1.62 ( 0.51) | 1.60 (0.50) | 1.57 (0.49) | 1.57 (0.49) | 1.47 (0.49) | 1.40 (0.49) | |
3.00 | (µ, σ) | (4.00, 8.33) | (2.35, 4.00) | (2.08, 2.58) | (2.03, 1.86) | (2.04, 1.55) | (2.07, 1.37) | (2.10, 1.24) | (2.12, 1.13) | (2.15, 1.04) | (2.17, 0.96) | (2.24, 0.75) | (2.29, 0.61) |
3 | 1.05 (0.23) | 1.36 (0.60) | 1.77 (0.81) | 2.01 (0.83) | 2.02 (0.75) | 2.00 (0.68) | 1.95 (0.60) | 1.93 (0.54) | 1.90 (0.50) | 1.90 (0.46) | 1.88 (0.36) | 1.89 (0.31) | |
5 | 1.00 (0.07) | 1.18 (0.40) | 1.39 (0.55) | 1.57 (0.61) | 1.57 (0.57) | 1.55 (0.54) | 1.52 (0.53) | 1.51 (0.51) | 1.47 (0.50) | 1.45 (0.49) | 1.35 (0.47) | 1.25 (0.43) | |
7 | 1.00 (0.01) | 1.04 (0.19) | 1.21 (0.42) | 1.34 (0.49) | 1.33 (0.48) | 1.29 ( 0.45) | 1.24 (0.43) | 1.22 (0.41) | 1.17 (0.38) | 1.14 (0.35) | 1.04 (0.21) | 1.01 (0.12) | |
4.00 | (µ, σ) | (5.12, 9.07) | (3.61, 5.53) | (3.15, 3.99) | (2.93, 2.81) | (2.86, 2.07) | (2.86, 1.68) | (2.88, 1.48) | (2.91, 1.35) | (2.94, 1.24) | (2.96, 1.15) | (3.04, 0.89) | (3.10, 0.73) |
3 | 1.03 (0.19) | 1.16 (0.39) | 1.26 (0.49) | 1.42 (0.59) | 1.48 (0.59) | 1.47 (0.55) | 1.43 (0.51) | 1.41 (0.50) | 1.38 (0.49) | 1.36 (0.48) | 1.27 (0.44) | 1.19 (0.39) | |
5 | 1.00 (0.04) | 1.02 (0.16) | 1.08 (0.27) | 1.16 (0.38) | 1.19 (0.40) | 1.15 ( 0.36) | 1.12 (0.33) | 1.09 (0.29) | 1.06 (0.25) | 1.05 (0.21) | 1.00 (0.09) | 1.00 (0.03) | |
7 | 1.00 (0.01) | 1.00 (0.06) | 1.02 (0.14) | 1.05 (0.23) | 1.06 (0.25) | 1.04 (0.20) | 1.02 (0.16) | 1.01 (0.11) | 1.00 (0.08) | 1.00 (0.05) | 1.27 (0.47) | 1.00 (0.00) | |