Ambar Amarelo wrote:
Hi folks, sorry for this beginner question but what means a p-value = NA on
a menn-whitney test?
v1 <- c(0.022, 0.022, 0.022, 0.022, 0.022, 0.022)
v2 <- c(0.022, 0.022, 0.022, 0.022, 0.022)
wilcox.test(v1, v2, PAIRED=FALSE)
W = 15, p-value = NA
I know that there's no statistical difference between v1 and v2, so why my
p-value is not ONE ??
Can I consider p-value= NA as ONE ??
what i do when get this type of value on wilcox.test ???
PS: sorry for my bad english.
[[alternative HTML version deleted]]
Did you read the help page? If there are ties, then a
Normal approximation is used. So how would you do a
Normal approximation? Try it "by hand" - you have a
small enough amount of data.
Try also a t.test() and see what message it gives you.
BTW, there is no PAIRED argument to wilcox.test().
--
Peter Ehlers
University of Calgary
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