Xh. Zhou et Wz. Tu, Comparison of several independent population means when their samples contain log-normal and possibly zero observations, BIOMETRICS, 55(2), 1999, pp. 645-651
In this paper, we consider the problem of testing the mean equality of seve
ral independent populations that contain log-normal and possibly zero obser
vations. We first showed that the currently used methods in statistical pra
ctice, including the nonparametric Kruskal-Wallis test, the standard ANOVA
F-test and its two modified versions, the Welch test and the Brown-Forsythe
test, could have poor Type I error control. Then we propose a likelihood r
atio test that is shown to have much better Type I error control than the e
xisting methods. Finally, we analyze two real data sets that motivated our
study using the proposed test.