Displaying 20 results from an estimated 1000 matches similar to: "Finding the Degrees of Freedom in a Wilcoxon Test"
2005 May 16
1
Mann-Whitney & Wilcoxon Rank Sum
Hello,
I am hoping someone could shed some light into the Wilcoxon Rank Sum Test
for me? In looking through Stats references, the Mann-Whitney U-test and
the Wilcoxon Rank Sum Test are statistically equivalent. When using the
following dataset:
m <- c(2.0863,2.1340,2.1008,1.9565,2.0413,NA,NA)
f <- c(1.8938,1.9709,1.8613,2.0836,1.9485,2.0630,1.9143)
and the wilcox.test command as
2003 Feb 15
2
How to code a bootstrap version of the Wilcoxon-Mann-Whitney test (and variants)?
Hello,
can someone please help me with coding a function for a bootstrap WMW test (package boot, R under Windows, version 1.6.2)?
2002 Mar 20
1
Wilcoxon Rank Sum Test
How does R compute the p-value in the Wilcoxon Rank Sum Test?
If I have the test statistics, can I get the p-value using the function
pwilcox?
Thanks
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the
2005 Nov 23
2
wilcoxon.test?
Hello there,
I would like to do a Wilcoxon matched pairs signed rank sum test in R
and tried the function wilcoxon.test. Is it in the "base" library? If
not, please let me know which library it is in.
Thank you in advance for your help
Lisa Wang
Biostatistician
Princess Margaret Hospital
Toronto, Ca
2011 Oct 31
2
one sample Wilcoxon test using 'coin'
Hi,
R allows me to run a one sample Wilcoxon test like this:
wilcox.test(c(1,3.5,2.1,4,1.5,5), mu=2, exact=TRUE)
The function 'wilcoxsign_test' from the package 'coin' should (I
suppose) be able to calculate exact p values even if there are ties in
the ranks. However, I couldn't find information on how to run a one
sample test using 'wilcoxsign_test' like in the
2011 Apr 13
2
Wilcoxon rank sum in unbalanced design
Hi everyone!
I need to perform a Wilcoxon rank sum test, but I have some ties and the
groups have different size also. When I deal with ties I use the
wilcox.exact function, how can I solve the different size problem using this
function?
thanks
net
--
View this message in context: http://r.789695.n4.nabble.com/Wilcoxon-rank-sum-in-unbalanced-design-tp3447400p3447400.html
Sent from the R help
2012 Feb 09
2
AUC, C-index and p-value of Wilcoxon
Dear all,
I am using the ROCR library to compute the AUC and also the Hmisc library
to compute the C-index of a predictor and a group variable. The results of
AUC and C-index are similar and give a value of about 0.57. The Wilcoxon
p-value is <0.001! Why the AUC is showing small value and the p-value is
high significant? The AUC is based on Wilcoxon calculation?
Many thanks,
Lina
2003 Dec 01
2
wilcoxon-pratt signed rank test in R - drug-effiacy
Hi.
I'm going to introduce the R-package for a group of medical doctors later
this week and is a little confused about there use of a test named
"willcoxon-pratt" for testing if the clinical and biochemical markers has
decreased significantly after the use of some drugs for a group of patients.
Looking into the R-functions I would in R recommand using a matched-pairs
Wilcoxon
2017 Jun 23
2
Paired Weighted Wilcoxon test in R
Dear R-users,
I?m trying to perform a non-parametric statistical pairwise comparison of two samples "x" and "y" using the Wilcoxon test in R, but each of the pairs have a weight associated.
An example of my data is the following one:
set.seed(9)
x <- sample(x = c(1:100), size = 20, replace = TRUE)
y <- sample(x = c(1:100), size = 20, replace = TRUE)
weight <-
2009 Feb 02
1
wilcoxon test with bonferroni correction
Hi!
I need to run a wilcoxon (Mann-whitly, in fact) test with bonferroni
correction, as I am running 10 consecutive wilcoxon test not
independent, and I know that bonferroni will partially correct for
this problem, but I have no idea how to do it with R, I have been
looking in the archive but couldn't understand how to do it.
The format I am using at the moment is
r4_o <-
[1]
2009 Oct 23
4
How to apply the Wilcoxon test to a hole table at once?
Hi,
I have a data set:
> Dataset
X1 X2 X3 X4 X5 X6 X7 X8 X9 X10 X11 X12 X13 X14 X15 X16 X17
1 user1 m 22 19 28 24 12 18 9 7 4 5 4 7 5 7 9
2 user2 f 25 19 23 18 18 15 6 8 6 6 7 10 7 7 7
3 user3 f 28 21 24 18 15 12 10 6 7 9 5 10 5 9 5
4 user4 f 26 19 26 21 12 18 6 6 5 1 3 8 6 5 6
5 user5 m 21 22 26 18 9 6 4 6 1
2011 Jan 30
3
medians in Wilcoxon disagree with median function
I am sure I am opening myself up to looking stupid, but I have two samples
with medians of 613.5 and 189 (difference in location of 424 compared to
the difference suggested from the wilcoxon of 291.5)
> wilcox.test(pipwtCount,pipwdCount, conf.int=TRUE, na.rm=TRUE)
Wilcoxon rank sum test
data: pipwtCount and pipwdCount
W = 822, p-value = 0.01227
alternative hypothesis: true location
2012 Sep 19
1
Wilcoxon Test and Mean Ratios
Hello All,
I am writing to ask your opinion on how to interpret this case. I have two vectors "a" and "b" that I am trying to compare.
The wilcoxon test is giving me a pvalue of 5.139217e-303 of a over b with the alternative "greater". Now if I make a summary on each of them I have the following
> summary(a)
Min. 1st Qu. Median Mean 3rd Qu.
2010 Jun 23
3
Wilcoxon signed rank test and its requirements
Hi all,
I have a distribution, and take a sample of it. Then I compare that sample with the mean of the population like here in "Wilcoxon signed rank test with continuity correction":
> wilcox.test(Sample,mu=mean(All), alt="two.sided")
Wilcoxon signed rank test with continuity correction
data: AlphaNoteOnsetDists
V = 63855, p-value = 0.0002093
alternative hypothesis:
2005 Jan 22
1
Wilcoxon test for mixed design (between-within subjects)
Hallo,
is there any extension of the pairwise Wilcoxon test to a dependent
samples layout with replicates (or, in other terms, a one-way layout
with blocking and replicates)?
The Wilcoxon method with matched pairs works for the case of dependent
samples with one observation per block, while the Mann-Whitney test
works for independent samples, thus one single block and replicated
observations. Is
2010 Nov 24
2
Wilcoxon Rank Sum in R with a multiple testing correction
Hi there,
I'm a total newbie to R. I'd like to use a Wilcoxon Rank Sum test to compare
two populations of values. Further, I'd like to do this simultaneously for
114 sets of values. The two populations are C and N. The different sets of
values have arbitrary names (I'll call them a, b, c etc). The set-up is as
follows:
a b c d ....
C 2
C 3
C 5
C 9
C 4
2012 Jul 24
2
Wilcoxon V = 0
I am running a pairwise wilcoxon signed rank test, and I am not sure how to
interpret the result. I would like to see if there is a difference between
the values in conditions a and b. It doesn't seem possible to have a V = 0,
but a significant p value. Am I doing something wrong?
The command I used is this:
wilcox.test(x=a$x,y=b$x,paired=TRUE)
The output looks like this:
Wilcoxon
2005 Nov 14
1
effect sizes for Wilcoxon tests
Hello,
I use t.test for normal distributed and wilcox.test for non-normal
distributed samples.
It is easy to write a function for t.test that calculates the effect
size, because all parts of the formula are available from the t.test
result: r = sqrt(t*t / (t*t + df))
However, for Wilcoxon tests, the formula for effect sizes is:
r = Z / sqrt(N)
I wonder how I can calculate the Z-score in R for
2007 Jun 28
1
Wilcoxon Rank Sum Test.
Dear,
I'm using R software to evaluate Wilcoxon Rank Sum Test and I' getting one
Warning message as this:
> C1dea_com
[1] 1.000 0.345 0.200 0.208 0.508 0.480 0.545 0.563 0.451 0.683 0.380 0.913
1.000 0.506
> C1dea_sem
[1] 1.000 0.665 0.284 0.394 0.509 0.721 0.545 0.898 0.744 0.683 0.382 0.913
1.000 0.970
> wilcox.test(C1dea_sem,C1dea_com, paired = TRUE, alternative =
2011 Sep 15
1
How to compute the power of a wilcoxon test?
Hello All,
I posted a similar question before, but the direction was driven to whether
my case is suitable for a wilcoxon test. After research about the
appropriateness, I am pretty sure that a wilcoxon test is the right tool for
my case. But how to compute the power of the test is still an unanswered
question bothering me.
The basic stats of my two paired samples are:
mean1 = 0.0032, sd1 =