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. Author manuscript; available in PMC: 2006 Nov 2.
Published in final edited form as: Biometrics. 2006 Sep;62(3):803–812. doi: 10.1111/j.1541-0420.2005.00521.x

Table 3.

Empirical sizes of the proposed spline-based nominal 0.05-level tests for covariate effects of Si in the model λ(t|Si) = λ0(t) (no effect) and λ(t|Si) = λ0(t) exp{Si} (linear effect), i = 1, 2, . . . , n, expressed as percent. λ0(t) = 1; values of Si are as in Table 1. Results are based on 2000 simulations for each scenario. The binomial (N = 2000, p = 0.05) standard error for the entries is 0:49%.

Null hypothesis
n = 100
n = 200
Censoring distribution Number of distinct covariate values No effect Linear effect No effect Linear effect
Unit exponential 4 5.25 4.65 5.10 4.90
10 5.20 4.35 5.00 4.60
20 5.15 4.60 5.05 4.50
50 5.05 4.45 4.95 4.60
100 5.15 4.25 5.00 4.80
200 4.95 4.70
Uniform (0,1.5) 4 4.90 4.80 4.50 4.65
10 5.30 5.15 5.10 5.05
20 5.00 5.50 4.60 4.90
50 5.05 5.60 4.50 4.95
100 5.00 5.70 4.70 4.95
200 4.70 4.85