Displaying 20 results from an estimated 4000 matches similar to: "wilcox.test returned estimates"
2002 Oct 15
2
V-value in the wilcox.test resp. wilcox.exact
hi,
when performing a wilcox.test or a wilcox.exact i get results that looks
like this:
wilcox.exact(x, mu=.5)
Exact Wilcoxon signed rank test
data: x
V = 207, p-value = 0.0006905
alternative hypothesis: true mu is not equal to 0.5
the way i understand the wilcox.test (or wilcox.exact) the V-value
represents the summed up ranks of either the positive or negative
differences,
2010 Feb 22
2
Siegel-Tukey test for equal variability (code)
Hi, I recently ran into the problem that I needed a Siegel-Tukey test for
equal variability based on ranks. Maybe there is a package that has it
implemented, but I could not find it. So I programmed an R function to do
it. The Siegel-Tukey test requires to recode the ranks so that they express
variability rather than ascending order. This is essentially what the code
further below does. After the
2006 May 12
1
wilcox.exact function (PR#8856)
Full_Name: Patrick Hodgson
Version: 2.0
OS: solaris 2.9
Submission from: (NULL) (65.94.128.161)
The value reported for the parameter W in the function wilcox.exact appears to
be incorrect. I have checked the reference in the help file for this function
(Myles & Hollander 1973, as well as 2nd ed. 1999 by same authors) and it is
clear that W is the sum of the ranks of the data set with the
2005 Mar 02
2
wilcox.test statistics
Hi,
Could anyone provide the formula of the statistics which the wilcox.test
used for the two-sample rank-sum test? I got some statistics of 0 values,
but it is impossible to have 0 "rank-sum". Does the function use the
Mann-Whitney U test statistics? Thanks.
Ting-Yuan Liu
2013 Dec 16
1
Power calculations for Wilcox.test
Greetings, I'm working on some analyses where I need to calculate wilcox
tests for paired samples. In my current literature search I've found a
few papers on sample size determination for the wilcox test notably:
Sample Size Determination for Some Common Nonparametric Tests
Gottfried E. Noether
Journal of the American Statistical Association
2013 Jul 18
2
Orders of levels affecting wilcox.test() output
Good day all,
My first posting to this list. It looked like the best place to post this
question.
When running the wilcox.test(), I noticed that the output values change if
you change the ordering of the levels (example below which includes a
t.test for comparison). I think this has something to do with the change in
ranking order, but this doesn't make much sense as I would expect the
2010 Aug 09
1
Difference Between R: wilcox.test and STATA: signrank
This is my first post to the mailing list and I guess it's a pretty stupid
question but I can't figure it out. I hope this is the right forum for these
kind of questions.
Before I started using R I was using STATA to run a Wilcoxon signed-rank
test on two variables. See data below:
2001 Oct 26
2
wilcox.test point estimates perverse (PR#1150)
The point estimates produced by wilcox.test are perverse (not wrong, just
brain damaged). The Hodges-Lehmann estimator that goes with the signed
rank test is the median of the Walsh averages. The Hodges-Lehmann estimator
that goes with the rank sum test is the median of the pairwise differences.
wilcox.test agrees except that it uses the following very peculiar definition
of "sample
2019 Dec 07
5
Inconsistencies in wilcox.test
Hello,
Writing to share some things I've found about wilcox.test() that seem a
a bit inconsistent.
1. Inf values are not removed if paired=TRUE
# returns different results (Inf is removed):
wilcox.test(c(1,2,3,4), c(0,9,8,7))
wilcox.test(c(1,2,3,4), c(0,9,8,Inf))
# returns the same result (Inf is left as value with highest rank):
wilcox.test(c(1,2,3,4), c(0,9,8,7), paired=TRUE)
2010 Aug 10
1
one (small) sample wilcox.test confidence intervals
Dear R people,
I notice that the confidence intervals of a very small sample (e.g. n=6) derived from the one-sample wilcox.test are just the maximum and minimum values of the sample. This only occurs when the required confidence level is higher than 0.93. Example:
> sample <- c(1.22, 0.89, 1.14, 0.98, 1.37, 1.06)
> summary(sample)
Min. 1st Qu. Median Mean 3rd Qu. Max.
2008 Apr 30
1
What are ties? Wilcox u-test
Hi,
When I execute a Wilcox u-test on two variables I receive a warning :
'cannot compute exact p-value with ties'
- What are ties? What does this mean for my data?
- Is that a problem for significance testing?
- is there a way to overcome this problem?
I have different threads in this forum but it hard to find what the exact
meaning of this warning message is.
--
View this message in
2019 Dec 12
2
Inconsistencies in wilcox.test
>>>>> Karolis Koncevi?ius
>>>>> on Mon, 9 Dec 2019 23:43:36 +0200 writes:
> So I tried adding Infinity support for all cases.
> And it is (as could be expected) more complicated than I thought.
"Of course !" Thank you, Karolis, in any case!
> It is easy to add Inf support for the test. The problems start with conf.int=TRUE.
2019 Dec 07
2
Inconsistencies in wilcox.test
Thank you for a fast response. Nice to see this mailing list being so
alive.
Regarding Inf issue: I agree with your assessment that Inf should not be
removed. The code gave me an impression that Inf values were
intentionally removed (since is.finite() was used everywhere, except for
paired case). I will try to adjust my patch according to your feedback.
One more thing: it seems like you
2005 Jul 14
2
Partek has Dunn-Sidak Multiple Test Correction. Is this the same/similar to any of R's p.adjust.methods?
The Partek package (www.partek.com) allows only two selections for Multiple
Test Correction: Bonferroni and Dunn-Sidak. Can anyone suggest why Partek
implemented Dunn-Sidak and not the other methods that R has? Is there any
particular advantage to the Dunn-Sidak method?
R knows about these methods (in R 2.1.1):
> p.adjust.methods
[1] "holm" "hochberg" "hommel"
2005 Aug 17
1
trouble with wilcox.test
I'm having trouble with the wilcox.test command in R. To demonstrate the anomalous behavior of wilcox.test, consider
> wilcox.test(c(1.5,5.5), c(1:10000), exact = F)$p.value
[1] 0.01438390
> wilcox.test(c(1.5,5.5), c(1:10000), exact = T)$p.value
[1] 6.39808e-07 (this calculation takes noticeably longer).
> wilcox.test(c(1.5,5.5), c(1:20000), exact = T)$p.value
(R closes/crashes)
2003 Aug 06
1
wilcox.test, CI (PR#3666)
Full_Name: David Wooff
Version: 1.7.0
OS: i686-pc-linux-gnu
Submission from: (NULL) (129.234.4.10)
wilcox.test exits with error message when confidence interval required, under
some situations. I suspect this occurs when the data contain a zero and for some
data lengths only:
print(wilcox.test(c(2,1,4,3,6,-5,0),conf.int=T))
fails
print(wilcox.test(c(2,1,4,3,6,-5,0,1),conf.int=T))
works
2006 Sep 29
1
Confidence interval in the Wilcoxon exact test
Hi,
Two functions wilcox.exact and wilcox_test give slightly different confidence intervals of the difference of the medians: for example
y<-c(0,0,1.081,0.594,0,0.769,0,0.009,0,0,0.798,0.405,0.498,0.946,1.35,1.149,0.528)
x<-c(rep(1,10),rep(2,7))
aa<-wilcox.exact(y~x,conf.int=TRUE)
bb<-wilcox_test(y~factor(x),distribution="exact",conf.int=TRUE)
aa
bb
Does anyone know
2008 Nov 12
2
pairwise.wilcox.test
Un texte encapsul? et encod? dans un jeu de caract?res inconnu a ?t? nettoy?...
Nom : non disponible
URL : <https://stat.ethz.ch/pipermail/r-help/attachments/20081112/618073fe/attachment.pl>
2006 Nov 08
2
interprete wilcox.test results
Dear All,
I am using wilcox.test to test two samples, data_a and data_b, earch sample has 3 replicates, suppose data_a and data_b are 20*3 matrix. Then I used the following to test the null hypothesis (they are from same distribution.):
wilcox.test(x=data_a, y=data_b, alternative="g")
I got pvalue = 1.90806170863311e-09.
When I switched data_a and data_b by doing the following:
2009 Nov 01
1
wilcox.test construction in r
Hi, I am very confused with constructing the wilcox.test in R.
I have two populations 'original' and 'test'.
I want to know if the 'test' is generally 'lower' than original.
I use alpha of 0.05.
So do I write the function as wilcox.test(original, test, alternative="l")?
or wlcox.test(original, test, alternative = "g")?
or wilcox.test(test,