Skip to main content

Table 6 The empirical powers 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 unequal medians and sample sizes n 1 = 20, n 2 = 25, n 3 = 25, n 4 = 30

From: Comparing survival curves based on medians

Distributions and parameters Censoring rate BC TJ New
Uniform distribution
θ = (10,10,10.5,10)
a = (4,4,4,4)
c = (2,2,2,2)
0 0.169 0.133 0.140
0.1 0.171 0.153 0.126
0.2 0.175 0.186 0.117
0.3 0.177 0.216 0.104
Exponential distribution
θ = (10,10,10,10)
a = (0.1,0.15,0.15,0.1)
0 0.229 0.184 0.196
0.1 0.233 0.199 0.201
0.2 0.233 0.218 0.187
0.3 0.221 0.231 0.160
Log-normal distribution
θ = (log(10), log(14), log(14), log(10))
a = (1,1,1,1)
0 0.231 0.185 0.201
0.1 0.212 0.190 0.169
0.2 0.210 0.218 0.163
0.3 0.201 0.240 0.140
Two uniform and two exponential distributions
θ = (10,13,13-10log(2),10-10log(2))
a = (0.1,0.1,0.1,0.1)
c = (0.01,0.01,0.01,0.01)
0 0.277 0.229 0.234
0.1 0.266 0.270 0.190
0.2 0.264 0.295 0.172
0.3 0.258 0.315 0.158
Two uniform and two log-normal distributions
θ = (10,12,2.5,2.5)
a = (1,1,1,1)
c = (0.2,0.2,0.2,0.2)
0 0.288 0.218 0.275
0.1 0.250 0.257 0.240
0.2 0.249 0.294 0.218
0.3 0.253 0.329 0.197
Two log-normal and two exponential distributions
θ = (log(10),log(13),13-10log(2),10-10log(2)),
a = (1,1,0.1,0.1)
0 0.229 0.183 0.182
0.1 0.223 0.195 0.174
0.2 0.228 0.217 0.168
0.3 0.220 0.242 0.147