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. 2023 Dec 21;51(12):2420–2435. doi: 10.1080/02664763.2023.2297157

Table 1.

Coverage probabilities and (expected widths) of 95% CIs for the mean.

  Wald M-Wald Likelihood Score Wald M-Wald Likelihood Score
μ=3
n θ=.5 θ=1
10 .872(3.92) .918(5.00) .871(3.99) .873(5.04)
20 .882(3.75) .901(4.17) .923(7.87) .890(3.92) .896(2.90) .920(3.22) .902(2.95) .933(3.77)
30 .899(3.12) .915(3.34) .937(4.54) .909(3.24) .920(2.40) .934(2.57) .923(2.43) .938(2.81)
40 .910(2.74) .920(2.88) .941(3.53) .918(2.81) .926(2.09) .938(2.20) .931(2.11) .940(2.35)
50 .915(2.46) .922(2.56) .942(3.00) .921(2.51) .928(1.88) .936(1.96) .933(1.90) .945(2.06)
60 .919(2.25) .926(2.33) .943(2.65) .926(2.30) .930(1.72) .937(1.78) .933(1.73) .945(1.86)
70 .925(2.09) .931(2.15) .949(2.40) .929(2.13) .935(1.60) .940(1.64) .938(1.61) .947(1.70)
80 .928(1.96) .933(2.01) .946(2.21) .933(1.99) .936(1.50) .940(1.53) .938(1.50) .948(1.58)
90 .929(1.85) .933(1.89) .948(2.05) .934(1.88) .937(1.41) .943(1.44) .940(1.42) .949(1.48)
n θ=4 θ=10
10 .943(2.95) .975(3.76) .940(3.44) .932(2.88) .961(2.71) .986(3.45) .952(2.62) .952(2.90)
20 .938(2.02) .958(2.24) .938(2.12) .936(1.99) .950(1.82) .972(2.03) .946(1.79) .955(1.86)
30 .935(1.63) .950(1.75) .938(1.68) .941(1.62) .956(1.46) .969(1.56) .953(1.44) .953(1.47)
40 .941(1.41) .951(1.48) .941(1.44) .938(1.40) .949(1.25) .960(1.32) .947(1.24) .947(1.26)
50 .940(1.26) .950(1.31) .942(1.28) .938(1.25) .951(1.11) .958(1.16) .948(1.10) .949(1.11)
60 .946(1.15) .952(1.19) .947(1.17) .944(1.15) .950(1.01) .957(1.04) .947(1.00) .950(1.01)
70 .943(1.06) .950(1.09) .945(1.07) .943(1.06) .948(0.93) .955(0.96) .947(0.93) .950(0.93)
80 .946(0.99) .952(1.02) .948(1.01) .946(0.99) .945(0.87) .951(0.89) .945(0.86) .947(0.87)
90 .947(0.94) .952(0.96) .947(0.95) .946(0.94) .949(0.82) .954(0.83) .948(0.81) .950(0.82)
μ=5
n θ=.5 θ=1
10 .878(6.30) .922(8.03) .877(6.37) .891(14.4)
20 .883(6.09) .904(6.77) .923(10.6) .892(6.33) .905(4.55) .925(5.07) .910(4.63) .930(5.89)
30 .898(5.04) .915(5.40) .940(7.25) .910(5.21) .917(3.82) .934(4.09) .920(3.86) .938(4.45)
40 .907(4.42) .916(4.65) .938(5.68) .915(4.54) .925(3.31) .935(3.48) .929(3.34) .941(3.71)
50 .915(3.98) .924(4.14) .942(4.85) .922(4.07) .932(2.98) .942(3.10) .935(3.01) .941(3.25)
60 .918(3.66) .926(3.78) .950(4.30) .928(3.73) .931(2.73) .940(2.82) .937(2.75) .944(2.93)
70 .925(3.41) .930(3.51) .945(3.88) .929(3.46) .940(2.53) .946(2.61) .942(2.55) .945(2.70)
80 .929(3.18) .933(3.26) .941(3.58) .933(3.23) .940(2.37) .945(2.43) .941(2.39) .944(2.50)
90 .932(3.01) .936(3.07) .943(3.34) .935(3.04) .940(2.23) .945(2.28) .942(2.24) .948(2.35)
n θ=4 θ=10
10 .927(4.16) .969(5.31) .923(4.59) .920(4.05) .946(3.63) .983(4.62) .938(3.49) .943(3.76)
20 .932(2.89) .954(3.22) .936(3.02) .929(2.85) .953(2.47) .972(2.75) .949(2.42) .950(2.48)
30 .934(2.37) .951(2.54) .939(2.43) .932(2.35) .943(1.98) .956(2.12) .940(1.96) .945(1.99)
40 .936(2.05) .947(2.16) .939(2.10) .934(2.04) .950(1.70) .961(1.79) .949(1.69) .943(1.71)
50 .939(1.84) .947(1.92) .945(1.86) .938(1.83) .949(1.52) .958(1.58) .947(1.51) .948(1.52)
60 .942(1.68) .950(1.74) .941(1.70) .941(1.67) .947(1.38) .954(1.43) .945(1.37) .946(1.39)
70 .943(1.56) .949(1.60) .943(1.58) .941(1.55) .946(1.28) .952(1.31) .943(1.27) .944(1.28)
80 .942(1.46) .947(1.50) .945(1.47) .942(1.45) .942(1.19) .949(1.22) .941(1.19) .944(1.19)
90 .941(1.38) .947(1.41) .949(1.39) .940(1.37) .946(1.13) .952(1.15) .945(1.12) .947(1.13)
  Wald M-Wald Likelihood Score Wald M-Wald Likelihood Score
μ=10
n θ=.5 θ=1
10 .875(12.0) .922(15.4) .875(12.1) .896(20.7)
20 .880(11.8) .901(13.1) .884(12.3) .928(19.1) .909(8.76) .928(9.75) .915(8.91) .941(11.2)
30 .903(9.92) .917(10.6) .914(10.2) .942(14.1) .920(7.31) .935(7.83) .926(7.38) .943(8.51)
40 .909(8.66) .920(9.11) .918(8.88) .946(11.0) .926(6.36) .936(6.69) .931(6.41) .942(7.11)
50 .920(7.80) .929(8.12) .930(7.98) .945(9.47) .931(5.70) .940(5.93) .936(5.75) .943(6.24)
60 .920(7.16) .927(7.40) .928(7.28) .946(8.37) .935(5.23) .942(5.40) .938(5.27) .946(5.63)
70 .924(6.64) .931(6.83) .931(6.75) .947(7.59) .933(4.84) .939(4.98) .938(4.87) .946(5.16)
80 .930(6.23) .936(6.39) .941(6.32) .946(7.00) .938(4.53) .943(4.64) .942(4.55) .948(4.78)
90 .926(5.86) .931(5.99) .932(5.94) .947(6.50) .940(4.28) .945(4.38) .940(4.30) .948(4.49)
n θ=4 θ=10
10 .912(7.14) .961(9.09) .905(6.92) .915(7.75) .939(5.65) .978(7.20) .929(5.42) .932(5.69)
20 .923(5.08) .947(5.66) .921(5.01) .928(5.27) .935(3.90) .957(4.34) .929(3.82) .931(3.91)
30 .932(4.18) .949(4.48) .930(4.15) .936(4.29) .939(3.17) .953(3.39) .937(3.13) .937(3.17)
40 .939(3.62) .950(3.81) .939(3.59) .942(3.68) .943(2.75) .954(2.89) .941(2.72) .942(2.75)
50 .943(3.24) .951(3.37) .943(3.22) .945(3.29) .939(2.46) .949(2.56) .938(2.44) .940(2.46)
60 .939(2.97) .946(3.07) .938(2.95) .945(3.00) .945(2.25) .952(2.33) .943(2.23) .946(2.25)
70 .948(2.75) .954(2.83) .948(2.74) .948(2.78) .945(2.08) .950(2.14) .943(2.07) .945(2.08)
80 .944(2.57) .949(2.64) .943(2.57) .944(2.60) .946(1.95) .950(2.00) .945(1.94) .946(1.95)
90 .945(2.42) .949(2.48) .945(2.41) .946(2.44) .946(1.84) .952(1.88) .945(1.83) .945(1.84)
μ=20
n θ=.5 θ=1
10 .875(23.5) .923(29.9) .898(42.2) .870(23.5)
20 .883(23.3) .905(25.9) .892(24.3) .933(42.7) .906(17.2) .928(19.1) .909(17.4) .930(21.8)
30 .901(19.4) .916(20.8) .910(20.1) .941(27.4) .917(14.2) .931(15.2) .921(14.4) .943(16.5)
40 .915(17.1) .927(18.0) .924(17.6) .946(21.9) .926(12.3) .936(13.0) .933(12.5) .940(13.8)
50 .918(15.3) .926(16.0) .925(15.7) .947(18.6) .931(11.1) .939(11.5) .934(11.2) .948(12.1)
60 .921(14.1) .927(14.6) .929(14.4) .945(16.5) .932(10.2) .939(10.5) .936(10.2) .946(10.9)
70 .927(13.0) .932(13.4) .935(13.4) .952(15.0) .940(9.47) .944(9.74) .940(9.52) .947(10.0)
80 .926(12.2) .932(12.5) .932(12.4) .949(13.7) .937(8.86) .943(9.08) .939(8.90) .948(9.35)
90 .930(11.6) .934(11.9) .936(11.7) .948(12.8) .939(8.37) .943(8.56) .942(8.41) .948(8.79)
n θ=4 θ=10
10 .905(12.9) .956(16.5) .896(12.5) .906(13.8) .923(9.46) .968(12.0) .910(9.05) .914(9.44)
20 .921(9.38) .944(10.4) .919(9.24) .929(9.71) .931(6.71) .953(7.46) .925(6.57) .926(6.71)
30 .930(7.71) .944(8.26) .929(7.65) .938(7.90) .941(5.48) .955(5.87) .938(5.41) .940(5.48)
40 .937(6.70) .949(7.04) .936(6.65) .940(6.82) .938(4.76) .949(5.01) .937(4.71) .938(4.76)
50 .938(6.02) .948(6.26) .939(5.98) .943(6.10) .945(4.26) .955(4.43) .944(4.23) .945(4.26)
60 .941(5.51) .947(5.70) .939(5.48) .941(5.57) .941(3.90) .949(4.03) .940(3.87) .940(3.90)
70 .942(5.10) .948(5.24) .944(5.08) .945(5.15) .941(3.60) .948(3.71) .939(3.58) .943(3.60)
80 .945(4.77) .950(4.89) .945(4.75) .945(4.81) .946(3.38) .951(3.46) .945(3.36) .945(3.37)
90 .949(4.50) .954(4.60) .948(4.49) .948(4.54) .947(3.19) .952(3.26) .947(3.17) .945(3.18)