Table 3.
Averages and SEs for various estimators of the marginal survival functions S1 and S2 when the correct model (13) with θ = 4 is misspecified to the semiparametric normal model (4). The true marginal survival probabilities for both T1 and T2 are 0.850, 0.700 and 0.55, respectively.
t1 = 0.1625 | t1 = 0.3566 | t1 = 0.5978 | ||||||||
---|---|---|---|---|---|---|---|---|---|---|
Censoring | bias | SE | MSE | bias | SE | MSE | Bias | SE | MSE | |
(×10−3) | (×10−3) | (×10−3) | ||||||||
Censoring on T1 only | 0.0% | 0.036 | 1.3 | 0.0% | 0.049 | 2.4 | 0.2% | 0.063 | 3.9 | |
0.0% | 0.036 | 1.3 | 0.1% | 0.049 | 2.4 | 0.4% | 0.064 | 4.1 | ||
0.1% | 0.036 | 1.3 | 0.2% | 0.048 | 2.3 | 1.6% | 0.060 | 3.7 | ||
0.8% | 0.031 | 1.0 | 2.7% | 0.047 | 2.5 | 3.4% | 0.065 | 4.6 | ||
(0.036) | (0.050) | (0.062) | ||||||||
Univariate censoring | 0.1% | 0.043 | 1.8 | 0.1% | 0.057 | 3.2 | 0.4% | 0.071 | 5.0 | |
censoring | 0.0% | 0.036 | 1.3 | 0.1% | 0.049 | 2.4 | 0.4% | 0.064 | 4.1 | |
0.1% | 0.041 | 1.7 | 0.3% | 0.054 | 2.9 | 1.1% | 0.069 | 4.8 | ||
0.6% | 0.030 | 0.9 | 2.4% | 0.046 | 2.4 | 3.4% | 0.061 | 4.1 | ||
(0.035) | (0.050) | (0.067) | ||||||||
Bivariate | −0.1% | 0.048 | 2.3 | 0.1% | 0.072 | 5.1 | −0.4% | 0.100 | 10.0 | |
censoring | 0.0% | 0.035 | 1.2 | 0.3% | 0.051 | 2.6 | 0.4% | 0.064 | 4.1 | |
0.0% | 0.047 | 2.2 | 0.6% | 0.065 | 4.2 | 2.3% | 0.069 | 4.9 | ||
0.9% | 0.031 | 1.0 | 1.9% | 0.047 | 2.4 | 1.0% | 0.063 | 4.0 | ||
(0.035) | (0.051) | (0.065) |
, the empirical hazard rate estimator; , the Kaplan-Meier estimator; , the redistributed empirical estimator; , the semiparametric maximum likelihood estimator. SEs; empirical standard errors; for the model based standard errors are displayed inside the brackets; only the estimates of the T1-survival are reported, as similar patterns were observed for the estimates of the T2-survival.