Table 4.
Simulation results from a Weibull model†
| Parameter | True | Results for discrete time model, | Results for discrete time model, | ||||
|---|---|---|---|---|---|---|---|
| value | 6 intervals | 3 intervals | |||||
| Mean | Coverage | MSE | Mean | Coverage | MSE | ||
| Longitudinal | |||||||
| Intercept | 90 | 90.034 (1.108) | 0.958 | 1.225 | 90.041 (1.105) | 0.960 | 1.221 |
| Time | −1.7 | −1.700 (0.061) | 0.956 | 0.004 | −1.697 (0.061) | 0.954 | 0.004 |
| Sex (males) | 2 | 1.952 (1.584) | 0.947 | 2.505 | 1.952 (1.581) | 0.948 | 2.497 |
| Survival | |||||||
| Intercept | — | 2.150 (0.122) | — | — | 1.813 (0.132) | — | — |
| Time | — | −0.038 (0.024) | — | — | −0.039 (0.029) | — | — |
| Sex (males) | — | 0.163 (0.110) | — | — | 0.183 (0.126) | — | — |
| γ1 | — | 0.054 (0.004) | — | — | 0.061 (0.004) | — | — |
| Others | |||||||
| ν | 7 | 6.998 (0.082) | 0.945 | 0.007 | 7.000 (0.082) | 0.948 | 0.007 |
| σ1 | 25 | 24.932 (0.548) | 0.958 | 0.303 | 24.908 (0.546) | 0.958 | 0.305 |
†
Sample size 1000 and 500 replicates. Shown are the mean (with standard deviations in parentheses) parameter estimates, empirical coverage probabilities of nominal 95% confidence intervals and mean-squared errors MSE.