Table 2.
Estimated powers of nominal 0.05-level tests for proportional hazards of Si in the model λ(t|Si) = λ0(t) exp{Siγ(t)}, i = 1, 2, . . . , n, expressed as percent. λ0(t) = 1; Si is a single binary covariate defining two groups of equal size; γ(t) is the true alternative; n = 200. Censoring distribution is uniform on (0, 2). Tests and alternatives are as described in the text. Results are based on 1000 simulations for each scenario. The maximum binomial (N = 1000, p = 0:50) standard error for the entries is 1:58%.
| Alternative
|
|||||
|---|---|---|---|---|---|
| Test | Curve 1 | Curve 2 | Curve 3 | Curve 4 | Curve 5 |
| Spline-based | 90.8 | 78.4 | 47.6 | 37.3 | 28.6 |
| Linear | 90.5 | 78.8 | 51.4 | 10.1 | 30.4 |
| Quadratic | 79.7 | 65.3 | 50.0 | 13.8 | 36.6 |
| Log | 93.3 | 75.8 | 37.4 | 32.1 | 15.5 |
| Optimal | 93.3 | 81.7 | 51.4 | 91.5 | 46.6 |