| Case 1; Both X1 and X2 are continuous |  | Case 2; X1 is continuous and X2 is binary | |||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 |  | Correlation r=0 |  | Correlation r=0.5 |  | Correlation r=0 |  | Correlation r=0.5 | ||||||||||||
Covariance matrix imputed with IPD | ||||||||||||||||||||
 |  | -2 | -1 | 0 | 1 |  | -2 | -1 | 0 | 1 |  | -2 | -1 | 0 | 1 |  | -2 | -1 | 0 | 1 |
Bias | Proposed method | |||||||||||||||||||
 | α 0 | -0.002 | 0.024 | 0.030 | 0.000 |  | 0.028 | 0.029 | 0.043 | 0.052 |  | 0.025 | 0.022 | 0.013 | -0.040 |  | 0.057 | 0.037 | 0.006 | -0.006 |
 | α 1 | -0.052 | -0.022 | -0.001 | 0.086 |  | -0.049 | -0.024 | -0.011 | 0.083 |  | -0.050 | -0.015 | -0.003 | 0.071 |  | -0.064 | -0.017 | 0.002 | 0.025 |
 | α 2 | 0.038 | 0.022 | 0.012 | 0.097 |  | 0.030 | 0.018 | 0.010 | 0.058 |  | 0.044 | 0.007 | 0.018 | 0.266 |  | 0.049 | 0.001 | 0.012 | 0.488 |
 | M1: Full set only | |||||||||||||||||||
 | α 0 | 0.011 | 0.010 | -0.018 | -0.365 |  | 0.009 | -0.009 | -0.029 | -0.058 |  | 0.011 | 0.016 | -0.004 | -0.016 |  | 0.027 | 0.011 | -0.007 | -0.002 |
 | α 1 | -0.009 | 0.003 | 0.011 | 0.061 |  | 0.001 | 0.002 | 0.000 | 0.082 |  | -0.001 | 0.002 | 0.000 | 0.029 |  | -0.006 | 0.001 | -0.004 | 0.012 |
 | α 2 | 0.001 | -0.009 | -0.019 | 0.061 |  | 0.001 | 0.000 | -0.015 | 0.023 |  | 0.008 | -0.027 | -0.006 | 0.124 |  | 0.027 | -0.008 | 0.001 | 0.272 |
 | M2: Mean imputation | |||||||||||||||||||
 | α 0 | 2.166 | 1.551 | -0.193 | -1.275 |  | 1.197 | 0.724 | -0.145 | -0.590 |  | 2.930 | 2.116 | 0.048 | -1.131 |  | 2.612 | 1.789 | 0.050 | -0.841 |
 | α 1 | -1.807 | -0.818 | -0.171 | 0.218 |  | -1.921 | -1.101 | -0.415 | -0.135 |  | -1.334 | -0.756 | -0.082 | 0.203 |  | -1.385 | -0.800 | -0.142 | 0.075 |
 | α 2 | 0.811 | 0.218 | -0.034 | 0.226 |  | 1.543 | 0.940 | 0.109 | -0.145 |  | 0.034 | -0.138 | -0.069 | -0.460 |  | 1.292 | 0.778 | 0.010 | -1.356 |
MSE | Proposed method | |||||||||||||||||||
 | α 0 | 0.123 | 0.098 | 0.205 | 0.803 |  | 0.085 | 0.056 | 0.101 | 0.251 |  | 0.096 | 0.055 | 0.065 | 0.136 |  | 0.074 | 0.044 | 0.047 | 0.086 |
 | α 1 | 0.045 | 0.021 | 0.037 | 0.215 |  | 0.060 | 0.025 | 0.057 | 0.181 |  | 0.051 | 0.015 | 0.012 | 0.058 |  | 0.057 | 0.017 | 0.016 | 0.059 |
 | α 2 | 0.033 | 0.022 | 0.034 | 0.204 |  | 0.044 | 0.027 | 0.060 | 0.188 |  | 0.144 | 0.055 | 0.051 | 0.247 |  | 0.173 | 0.070 | 0.076 | 0.486 |
 | M1: Full set only | |||||||||||||||||||
 | α 0 | 0.248 | 0.208 | 0.453 | 7.960 |  | 0.160 | 0.131 | 0.274 | 0.707 |  | 0.195 | 0.116 | 0.142 | 0.300 |  | 0.169 | 0.099 | 0.108 | 0.197 |
 | α 1 | 0.068 | 0.033 | 0.068 | 0.620 |  | 0.075 | 0.033 | 0.094 | 0.398 |  | 0.096 | 0.027 | 0.025 | 0.112 |  | 0.099 | 0.030 | 0.028 | 0.112 |
 | α 2 | 0.038 | 0.032 | 0.093 | 0.591 |  | 0.045 | 0.034 | 0.118 | 0.570 |  | 0.162 | 0.077 | 0.103 | 2.165 |  | 0.190 | 0.095 | 0.120 | 4.883 |
 | M2: Mean imputation | |||||||||||||||||||
 | α 0 | 5.290 | 2.663 | 0.236 | 1.929 |  | 1.633 | 0.625 | 0.113 | 0.638 |  | 8.771 | 4.532 | 0.039 | 1.372 |  | 6.912 | 3.242 | 0.033 | 0.775 |
 | α 1 | 3.694 | 0.806 | 0.071 | 0.242 |  | 3.771 | 1.254 | 0.214 | 0.213 |  | 2.083 | 0.601 | 0.012 | 0.126 |  | 2.075 | 0.661 | 0.026 | 0.087 |
 | α 2 | 0.870 | 0.195 | 0.088 | 0.209 |  | 2.424 | 0.934 | 0.091 | 0.333 |  | 0.310 | 0.098 | 0.079 | 2.058 |  | 1.919 | 0.676 | 0.065 | 5.396 |
Convergence proportion (%) | ||||||||||||||||||||
 |  | 100 | 100 | 99.1 | 61.5 |  | 100 | 100 | 98.4 | 67.3 |  | 100 | 100 | 98.4 | 61.2 |  | 100 | 100 | 98.4 | 60.3 |
True Covariance matrix | ||||||||||||||||||||
 |  | -2 | -1 | 0 | 1 |  | -2 | -1 | 0 | 1 |  | -2 | -1 | 0 | 1 |  | -2 | -1 | 0 | 1 |
Bias | Proposed method | |||||||||||||||||||
 | α 0 | 0.032 | 0.034 | 0.049 | 0.215 |  | 0.058 | 0.038 | 0.050 | 0.185 |  | 0.059 | 0.045 | 0.028 | 0.032 |  | 0.075 | 0.054 | 0.014 | 0.041 |
 | α 1 | -0.118 | -0.048 | -0.005 | 0.099 |  | -0.110 | -0.046 | -0.010 | 0.105 |  | -0.116 | -0.037 | -0.004 | 0.072 |  | -0.117 | -0.036 | 0.003 | 0.036 |
 | α 2 | 0.070 | 0.055 | 0.052 | 0.104 |  | 0.055 | 0.049 | 0.058 | 0.096 |  | 0.082 | 0.036 | 0.039 | 0.250 |  | 0.072 | 0.023 | 0.037 | 0.462 |
MSE | Proposed method | |||||||||||||||||||
 | α 0 | 0.111 | 0.089 | 0.196 | 0.690 |  | 0.077 | 0.053 | 0.094 | 0.204 |  | 0.091 | 0.054 | 0.065 | 0.123 |  | 0.071 | 0.043 | 0.046 | 0.080 |
 | α 1 | 0.050 | 0.021 | 0.034 | 0.161 |  | 0.061 | 0.024 | 0.050 | 0.125 |  | 0.057 | 0.015 | 0.012 | 0.050 |  | 0.062 | 0.017 | 0.015 | 0.051 |
 | α 2 | 0.031 | 0.022 | 0.032 | 0.146 |  | 0.039 | 0.026 | 0.053 | 0.136 |  | 0.133 | 0.049 | 0.049 | 0.215 |  | 0.145 | 0.060 | 0.069 | 0.417 |
Convergence proportion (%) | ||||||||||||||||||||
 |  | 100 | 100 | 99.1 | 61.5 |  | 100 | 100 | 98.4 | 67.3 |  | 100 | 100 | 98.4 | 61.2 |  | 100 | 100 | 98.4 | 60.3 |