我在 Kruskal-Wallis 测试后进行事后比较。我正在使用PMCMR包。
> posthoc.kruskal.nemenyi.test( preference ~ instrument)
Pairwise comparisons using Tukey and Kramer (Nemenyi) test
with Tukey-Dist approximation for independent samples
data: preference by instrument
Cello Drums Guitar
Drums 0.157 - -
Guitar 0.400 0.953 -
Harp 0.013 0.783 0.458
P value adjustment method: none
Warning message:
In posthoc.kruskal.nemenyi.test.default(c(50L, 50L, 50L, 50L, 49L, :
Ties are present, p-values are not corrected.
我对警告信息感到困惑。谁能解释它的含义以及我如何纠正它?