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Table 2 The empirical type I error rates of the tests at the significance level 0.05 when the survival times have uniform, exponential, log-normal,uniform and exponential, uniform and log-normal, or exponential and log-normal distributions with equal medians but unequal variances and sample sizes n 1 = 100, n 2 = 150, n 3 = 150, n 4 = 200

From: Comparing survival curves based on medians

Distributions and parameters Censoring rate BC TJ New
Uniform distribution
θ = (10,10,10,10)
a = (4,4,4,4)
c = (2,3,4,5)
0 0.061 0.057 0.058
0.1 0.057 0.068 0.053
0.2 0.061 0.089 0.054
0.3 0.062 0.109 0.053
Exponential distribution
θ = (10-2log(2),10-3log(2),
  10-4log(2),10-5log(2))
a = (1/2,1/3,1/4,1/5)
0 0.060 0.057 0.058
0.1 0.067 0.071 0.062
0.2 0.062 0.079 0.057
0.3 0.064 0.098 0.057
Log-normal distribution
θ = (log(10), log(10), log(10), log(10))
a = (0.2, 0.3, 0.4, 0.5)
0 0.057 0.053 0.055
0.1 0.063 0.073 0.059
0.2 0.064 0.094 0.058
0.3 0.060 0.117 0.054
Two uniform and two exponential distributions
θ = (10, 10, 10-10log(2),10-10log(2))
a = (0.1, 0.1, 0.1, 0.1)
c = (0.01, 0.01, 0.01, 0.01)
0 0.055 0.050 0.052
0.1 0.053 0.080 0.047
0.2 0.055 0.102 0.049
0.3 0.059 0.118 0.051
Two uniform and two log-normal distributions
θ = (10,10, log(10), log(10))
a = (5,5,0.3,0.3)
c = (2,2,2,2)
0 0.058 0.081 0.054
0.1 0.063 0.087 0.057
0.2 0.061 0.107 0.054
0.3 0.055 0.123 0.048
Two log-normal and two exponential distributions
θ = (log(10), log(10),10-log(2)/0.3,10-log(2)/0.3)
a = (0.3,0.3,0.3,0.3)
0 0.052 0.049 0.049
0.1 0.050 0.058 0.047
0.2 0.058 0.082 0.054
0.3 0.056 0.095 0.050