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. Author manuscript; available in PMC: 2018 Aug 3.
Published in final edited form as: J Am Stat Assoc. 2017 Jun 29;112(520):1571–1586. doi: 10.1080/01621459.2016.1222286

Table 2.

Simulation results for length-biased data (20% and 40% censoring rates); Bias: estimated bias of the estimates; SE: estimated variances of the estimates; SEE: averages of the resampled variance estimates; ECP: empirical coverage probabilities of the 95% Wald-type confidence intervals; MSE: mean squared error of the estimates.

Censoring τ Estimators n = 200 n = 400


Bias SE SEE ECP MSE Bias SE SEE ECP MSE
20% 0.25 β̂(0)(τ) −0.042 0.248 0.283 0.972 0.063 −0.005 0.130 0.128 0.956 0.035
β̂(1)(τ) −0.014 0.486 0.503 0.952 0.256 −0.043 0.304 0.331 0.970 0.122
β̂(2)(τ) −0.004 0.255 0.244 0.944 0.065 0.001 0.129 0.114 0.928 0.031
β̂(0)(τ)Naive 0.307 0.117 0.095 0.212 0.108 0.166 0.048 0.085 0.400 0.030
β̂(1)(τ)Naive 0.854 0.230 0.160 0.148 0.756 0.814 0.085 0.120 0.000 0.670
β̂(2)(τ)Naive 0.270 0.349 0.337 0.820 0.199 0.054 0.274 0.236 0.878 0.078
0.50 β̂(0)(τ) −0.016 0.145 0.185 0.966 0.021 −0.014 0.111 0.130 0.966 0.012
β̂(1)(τ) 0.020 0.323 0.363 0.962 0.105 −0.001 0.229 0.283 0.982 0.052
β̂(2)(τ) −0.013 0.168 0.150 0.926 0.028 0.007 0.114 0.104 0.924 0.013
β̂(0)(τ)Naive 0.302 0.039 0.049 0.890 0.002 0.000 0.004 0.049 0.900 0.000
β̂(1)(τ)Naive 0.277 0.172 0.170 0.652 0.121 −0.555 0.042 0.085 0.000 0.309
β̂(2)(τ)Naive 0.141 0.322 0.295 0.856 0.123 0.002 0.263 0.253 0.978 0.069

40% 0.25 β̂(0)(τ) −0.033 0.238 0.263 0.966 0.063 −0.008 0.132 0.125 0.950 0.036
β̂(1)(τ) 0.022 0.511 0.505 0.936 0.256 −0.031 0.312 0.291 0.936 0.112
β̂(2)(τ) −0.007 0.244 0.215 0.920 0.065 0.003 0.126 0.118 0.958 0.031
β̂(0)(τ)Naive 0.261 0.114 0.130 0.472 0.081 0.248 0.087 0.088 0.248 0.069
β̂(1)(τ)Naive 0.890 0.177 0.194 0.004 0.823 0.891 0.128 0.132 0.000 0.811
β̂(2)(τ)Naive 0.262 0.347 0.364 0.886 0.189 0.283 0.236 0.251 0.806 0.136
0.50 β̂(0)(τ) −0.011 0.142 0.188 0.964 0.020 −0.012 0.117 0.129 0.952 0.013
β̂(1)(τ) 0.041 0.315 0.362 0.968 0.101 0.006 0.237 0.280 0.968 0.054
β̂(2)(τ) −0.025 0.166 0.155 0.938 0.028 0.001 0.111 0.105 0.922 0.013
β̂(0)(τ)Naive 0.250 0.124 0.127 0.466 0.078 0.248 0.080 0.088 0.206 0.068
β̂(1)(τ)Naive 1.017 0.200 0.202 0.000 1.074 1.020 0.134 0.140 0.000 1.059
β̂(2)(τ)Naive 0.522 0.360 0.380 0.724 0.402 0.549 0.249 0.263 0.452 0.363