Table 1.

p-values for testing the difference of survival prognosis (good vs. poor) under the three copulas with selected values of α (Kendall’s tau takes −0.75, −0.46, 0, 0.33, 0.46, 0.50, 0.75).

		Prognostic Index (PI)
		Emura and Chen [41]	Chen et al. [6]
Clayton copula	$\alpha =1$ (tau = 0.33)	0.065	0.036
	$\alpha =2$ (tau = 0.50)	0.036	0.036
	$\alpha =4$ (tau = 0.75)	0.021	0.036
	$\alpha =15$ (tau = 0.88)	0.011	0.029
Gumbel copula	$\alpha =0$ (tau = 0.00)	0.171	0.040
	$\alpha =1$ (tau = 0.50)	0.058	0.029
	$\alpha =2$ (tau = 0.75)	0.028	0.029
	$\alpha =10$ (tau = 0.91)	0.011	0.025
Frank copula	$\alpha =-14$ (tau = −0.75)	0.360	0.059
	$\alpha =-5$ (tau = −0.46)	0.307	0.054
	$\alpha =5$ (tau = 0.46)	0.054	0.034
	$\alpha =14$ (tau = 0.75)	0.018	0.032

Notes: The PI is either 16-gene PI of Emura and Chen [41] or the 16-gene PI of Chen et al. [6]. The p-value is obtained by N = 10,000 permutations.