Table 8 Performance comparison of alternative estimators: variance of risk estimates. Results obtained on average over 100 realizations generated under two different population size scenarios and 3 types of risk map (1 = observed, 2 = smooth, 3 = random). Poisson kriging was conducted with the semivariogram estimated from the underlying risk values (true γR(h)) or the simulated mortality rates. Bold numbers refer to best performances (i.e. the variance of risk estimates is the closest to the true risk variance reported in the first row) outside the ideal case where the true semivariogram of risk is known.
Estimators | WF population | BF population | ||||
|---|---|---|---|---|---|---|
BREAST CANCER | Scenario 1 | Scenario 2 | Scenario 3 | Scenario 1 | Scenario 2 | Scenario 3 |
True risk values | 7.891 | 5.982 | 7.891 | 7.891 | 5.982 | 7.891 |
Population-weighted average | 5.635 | 4.560 | 0.346 | 8.538 | 6.881 | 3.035 |
Global Empirical Bayes | 3.628 | 1.722 | 5.178 | 0.290 | 0.145 | 1.026 |
Local Empirical Bayes | 6.571 | 4.941 | 5.257 | 9.364 | 8.576 | 5.339 |
Poisson kriging (true γR(h)) | 6.792 | 5.176 | 5.561 | 8.156 | 6.781 | 4.161 |
Poisson kriging | 6.922 | 5.093 | 5.498 | 8.332 | 7.044 | 4.143 |
CERVIX CANCER | Â | Â | Â | Â | Â | Â |
True risk values | 0.946 | 0.596 | 0.946 | 0.946 | 0.596 | 0.946 |
Population-weighted average | 0.485 | 0.498 | 0.055 | 0.909 | 0.918 | 0.422 |
Global Empirical Bayes | 0.474 | 0.213 | 0.593 | 0.132 | 0.050 | 0.162 |
Local Empirical Bayes | 0.727 | 0.538 | 0.625 | 3.197 | 2.059 | 2.746 |
Poisson kriging (true γR(h)) | 0.793 | 0.599 | 0.671 | 0.941 | 0.910 | 0.550 |
Poisson kriging | 0.804 | 0.596 | 0.607 | 1.269 | 1.137 | 0.690 |