I am using the package PMCMR
to perform a postdoc Kruskal-Nemenyi test.
When I run the test with the default settings:
posthoc.kruskal.nemenyi.test(x=coastal$HIGH_MORTGAGE, g=coastal$SIZECLASS, method="Tukey")
I get the following results and warning:
Pairwise comparisons using Tukey and Kramer (Nemenyi) test
with Tukey-Dist approximation for independent samples
data: coastal$HIGH_MORTGAGE and coastal$SIZECLASS
Large Medium
Medium 0.931 -
Small 0.746 0.078
P value adjustment method: none
Warning message:
In posthoc.kruskal.nemenyi.test.default(x = coastal$HIGH_MORTGAGE, :
Ties are present, p-values are not corrected.*
When I run the test changing the distribution to Chisq to apply a correction for the ties, I still get the same results and the chi-square distribution is not used.
posthoc.kruskal.nemenyi.test(x=coastal$HIGH_MORTGAGE, g=coastal$SIZECLASS, method="Chisq")
Pairwise comparisons using Tukey and Kramer (Nemenyi) test
with Tukey-Dist approximation for independent samples
data: coastal$HIGH_MORTGAGE and coastal$SIZECLASS
Large Medium
Medium 0.931 -
Small 0.746 0.078
P value adjustment method: none
Warning message:
In posthoc.kruskal.nemenyi.test.default(x = coastal$HIGH_MORTGAGE, :
Ties are present, p-values are not corrected.
I would like to know if there is a bug in the package or if there is any methos I am not aware of to solve this.