Friedman & Paired Comparisons (Durbin-Conover)

[pstjacques]

I am conducting Friedman non-parametric test, followed by pairwise comparisons (Durbin-Conover). I was wondering if the p-values reported in the table are already adjusted for multiple comparisons?

[MAgojam]

Hi, @pstjacques.

The p values shown in the table are obtained as:
P value adjustment method: none
Take a look at the attached screenshot, where I use the Rj module and this little r script.

Code: Select all

library(PMCMR)
options(digits=5)
y <- data.matrix(data[1:6])
friedman.test(y)

# P value adjustment method: none
posthoc.friedman.conover.test(y, p.adj="none")

# P value adjustment method: bonferroni
posthoc.friedman.conover.test(y, p.adj="bonferroni")


ScreenShot.png (105.26 KiB) Viewed 831 times

Cheers,
Maurizio

[pstjacques]

Thanks very much for your response Maurizio! I'm a newbie to R, so it's helpful to see how you have used the Rj Module here.