Table 3 The ARL results of Bayesian Max-EWMA control chart as a result of a shift in Weibull parameters W(1, 1.5) with \(\gamma\) = 0.10 and considering subgroup size as 3, 5, and 7 under LLF.
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 | 3.24 (1.24) | 3.46 (0.75) | 3.53 (0.66) | 3.59 (0.60) | 3.62 (0.56) | 3.68 (0.53) | 3.76 (0.49) | 3.79 (0.47) | 3.85 (0.42) | 3.89 (0.37) | 3.96 (0.24) | 3.95 (0.23) | |
5 | 2.53 (0.80) | 2.70 (0.56) | 2.77 (0.50) | 2.84 (0.43) | 2.90 (0.36) | 2.94 (0.29) | 2.97 (0.22) | 2.98 (0.17) | 2.99 (0.13) | 3.00 (0.10) | 2.99 (0.09) | 2.96 (0.17) | |
7 | 2.17 (0.64) | 2.27 (0.45) | 2.29 (0.45) | 2.33 (0.47) | 2.35 (0.47) | 2.39 (0.48) | 2.46 (0.49) | 2.49 (0.49) | 2.57 (0.49) | 2.61 (0.48) | 2.68 (0.46) | 2.44 (0.49) | |
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 | 2.65 (1.14) | 6.41 (2.40) | 6.70 (2.17) | 6.91 (1.96) | 7.21 (1.82) | 7.41 (1.67) | 7.50 (1.57) | 7.53 (1.50) | 7.32 (1.40) | 7.03 (1.36) | 8.38 (1.89) | 5.19 (0.91) | |
5 | 1.94 (0.71) | 4.75 (1.50) | 4.92 (1.31) | 5.07 (1.22) | 5.24 (1.09) | 5.47 (1.47) | 5.30 (0.90) | 5.20 (0.86) | 4.96 (0.82) | 4.68 (0.78) | 3.87 (0.61) | 3.10 (0.36) | |
7 | 1.64 (0.57) | 3.94 (1.11) | 4.06 (0.98) | 4.18 (0.88) | 4.34 (0.83) | 4.35 (0.72) | 4.35 (0.67) | 4.21 (0.63) | 3.99 (0.62) | 3.72 (0.59) | 3.09 (0.39) | 2.83 (0.37) | |
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 | 1.99 (0.87) | 13.27 (7.54) | 19.93 (12.35) | 24.68 (15.17) | 25.30 (14.43) | 21.44 (10.98) | 16.99 (7.88) | 13.86 (5.75) | 11.28 (4.02) | 9.75 (3.09) | 7.15 (2.87) | 5.87 (1.16) | |
5 | 1.47 (0.57) | 9.32 (4.39) | 13.42 (6.97) | 15.43 (7.74) | 14.67 (6.20) | 11.85 (4.34) | 9.16 (2.94) | 7.61 (7.67) | 6.46 (1.61) | 5.73 (1.28) | 4.42 (0.78) | 3.79 (0.59) | |
7 | 1.25 (0.44) | 7.47 (3.07) | 10.52 (4.92) | 11.77 (4.98) | 9.65 (3.16) | 8.69 (2.66) | 6.80 (1.85) | 5.72 (1.36) | 4.95 (1.04) | 4.43 (0.86) | 3.50 (0.57) | 3.04 (0.37) | |
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 | 1.66 (0.73) | 13.61 (8.24) | 54.88 (46.29) | 369.33 (367.12) | 173.35 (160.14) | 57.52 (45.17) | 29.07 (18.42) | 19.61 (10.19) | 15.23 (6.89) | 12.76 (5.05) | 8.05 (2.16) | 6.53 (1.46) | |
5 | 1.27 (0.46) | 8.47 (4.08) | 31.78 (23.77) | 370.89 (366.45) | 79.18 (67.14) | 24.21 (14.68) | 13.64 (6.01) | 10.17 (3.64) | 8.21 (2.46) | 7.13 (1.93) | 4.89 (0.94) | 4.14 (0.68) | |
7 | 1.11 (0.32) | 6.52 (2.76) | 23.51 (15.64) | 369.87 (360.22) | 49.61 (38.56) | 15.99 (7.87) | 9.67 (3.48) | 7.42 (2.17) | 6.17 (1.59) | 5.39 (1.23) | 3.83 (0.65) | 3.28 (0.49) | |
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 | 1.47 (0.64) | 8.56 (4.48) | 17.12 (10.83) | 25.07 (16.79) | 25.43 (16.08) | 23.33 (13.86) | 20.32 (10.33) | 17.52 (7.75) | 15.06 (5.84) | 13.33 (4.67) | 10.08 (3.00) | 7.28 (1.75) | |
5 | 1.17 (0.38) | 5.67 (2.38) | 11.37 (5.86) | 16.89 (10.07) | 16.33 (8.78) | 14.76 (6.96) | 12.62 (4.85) | 10.71 (3.48) | 9.05 (2.55) | 8.12 (2.13) | 5.55 (1.17) | 4.55 (0.82) | |
7 | 1.05 (0.22) | 4.50 (1.68) | 8.83 (4.01) | 13.31 (7.06) | 12.58 (5.94) | 11.15 (4.44) | 9.70 (3.18) | 8.19 (2.26) | 6.99 (1.74) | 6.22 (1.43) | 4.33 (0.82) | 3.60 (0.59) | |
\(\alpha\) | 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 | 1.36 (0.56) | 5.68 (2.59) | 8.58 (4.26) | 9.80 (4.77) | 9.54 (9.54) | 9.19 (3.63) | 8.77 (3.12) | 8.38 (2.65) | 8.09 (2.35) | 7.73 (2.00) | 6.91 (1.33) | 6.36 (1.01) | |
5 | 1.11 (0.31) | 3.98 (1.47) | 6.23 (2.54) | 7.05 (2.87) | 6.80 (2.50) | 6.56 (2.16) | 6.29 (1.88) | 6.02 (1.58) | 5.81 (1.37) | 5.54 (1.17) | 5.20 (1.16) | 4.47 (0.64) | |
7 | 1.02 (0.16) | 3.30 (1.10) | 5.08 (1.84) | 5.78 (2.14) | 5.57 (1.86) | 5.34 (1.56) | 5.13 (1.33) | 4.93 (1.15) | 4.75 (1.00) | 4.56 (0.86) | 4.07 (0.59) | 3.66 (0.52) | |
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 | 1.24 (0.46) | 2.20 (0.44) | 4.51 (1.83) | 4.68 (1.78) | 4.63 (1.57) | 4.49 (1.35) | 4.38 (1.19) | 4.25 (1.04) | 4.14 (0.92) | 4.12 (0.87) | 3.88 (0.65) | 3.74 (0.54) | |
5 | 1.05 (0.23) | 2.41 (0.82) | 3.40 (1.13) | 3.61 (1.16) | 3.55 (1.02) | 3.43 (0.89) | 3.35 (0.78) | 3.25 (0.69) | 3.19 (0.62) | 3.17 (0.57) | 3.02 (0.40) | 2.96 (0.29) | |
7 | 1.01 (0.10) | 1.62 (0.48) | 2.10 (0.35) | 2.44 (0.56) | 2.79 (0.69) | 3.15 (0.83) | 3.51 ( 1.00) | 3.50 (1.01) | 4.20 (1.36) | 4.53 (1.51) | 5.64 (2.13) | 2.46 (0.49) | |
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 | 1.18 (0.41) | 2.29 (0.95) | 3.14 (1.17) | 3.31 ( 1.13) | 3.27 (1.01) | 3.20 (0.88) | 3.12 (0.79) | 3.08 (0.71) | 3.02 (0.64) | 2.98 (0.60) | 2.87 (0.51) | 2.84 ( 0.39) | |
5 | 1.05 (0.22) | 1.75 (0.64) | 2.45 ( 0.78) | 2.58 ( 0.75) | 2.55 (0.67) | 2.50 (0.60) | 2.43 (0.55) | 2.39 (0.52) | 2.34 (0.48) | 2.31 (0.47) | 2.17 (0.38) | 2.08 (0.27) | |
7 | 1.00 (0.07) | 1.17 (0.38) | 2.09 (0.60) | 2.24 (0.58) | 2.65 (0.77) | 2.72 (0.80) | 2.91 (0.89) | 3.08 (0.96) | 3.19 ( 1.02) | 2.04 (0.23) | 2.00 (0.08) | 2.00 (0.01) | |
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 | 1.14 (0.37) | 1.76 (0.75) | 2.40 (0.93) | 2.63 (0.88) | 2.63 (0.78) | 2.58 (0.68) | 2.51 (0.62) | 2.48 (0.57) | 2.43 (0.53) | 2.39 (0.51) | 2.27 (0.45) | 2.17 (0.38) | |
5 | 1.02 ( 0.15) | 1.36 (0.51) | 1.88 (0.63) | 2.22 (0.70) | 2.48 (0.79) | 2.33 (0.86) | 2.06 (0.47) | 2.03 (0.32) | 2.01 (0.27) | 2.01 (0.22) | 1.99 (0.12) | 1.99 (0.06) | |
7 | 1.00 (0.05) | 1.17 (0.38) | 1.63 (0.54) | 1.83 (0.52) | 1.86 (0.46) | 1.85 (0.41) | 1.84 (0.38) | 1.85 (0.36) | 1.85 (0.35) | 1.85 (0.35) | 1.86 (0.33) | 1.99 ( 0.01) | |
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 | 1.10 (0.31) | 1.33 (0.53) | 1.59 (0.66) | 1.88 (0.71) | 1.98 (0.62) | 1.98 (0.52) | 1.97 (0.45) | 1.96 ( 0.39) | 1.95 ( 0.35) | 1.94 (0.31) | 1.96 (0.21) | 1.97 (0.16) | |
5 | 1.01 (0.12) | 1.09 (0.30) | 1.27 (0.46) | 1.48 (0.54) | 1.59 (0.53) | 1.59 (0.50) | 1.58 (0.49) | 1.58 (0.49) | 1.55 (0.51) | 1.53 (0.49) | 1.48 (0.49) | 1.42 (0.49) | |
7 | 1.00 (0.03) | 1.02 (0.16) | 1.12 (0.32) | 1.28 ( 0.45) | 1.34 (0.47) | 1.32 (0.46) | 1.27 (0.44) | 1.23 (0.42) | 1.21 (0.40) | 1.17 (0.38) | 1.07 (0.26) | 1.02 (0.16) | |