Displaying 20 results from an estimated 11000 matches similar to: "Interpreting the result of a Wilcoxon (Mann-Whitney U) test"
2005 Dec 20
1
Wilcoxon Mann-Whitney Rank Sum Test in R
An earlier post had posed the question: "Does anybody know what is relation
between 'T' value calculated by 'wilcox_test' function (coin package) and
more common 'W' value?"
I found the question interesting and ran the commands in R and SPSS. The W
reported by R did not seem to correspond to either Mann-Whitney U,
Wilcoxon W or the Z which I have more
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)?
2007 Aug 14
4
Mann-Whitney U
Hi,
Could someone please tell me how to perform a Mann-Whitney U test on a
dataset with 2 groups where one group has more data values than another?
I have split up my 2 groups into 2 columns in my .txt file i'm using with
R. Here is the code i have so far...
group1 <- c(LeafArea2)
group2 <- c(LeafArea1)
wilcox.test(group1, group2)
This code works for datasets with the same number
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
2012 May 29
2
Wilcoxon-Mann-Whitney U value: outcomes from different stat packages
Given this example
#start code
a<-c(0,70,50,100,70,650,1300,6900,1780,4930,1120,700,190,940,
760,100,300,36270,5610,249680,1760,4040,164890,17230,75140,1870,22380,5890,2430)
b<-c(0,0,10,30,50,440,1000,140,70,90,60,60,20,90,180,30,90,
3220,490,20790,290,740,5350,940,3910,0,640,850,260)
wilcox.test(a, b, paired=FALSE)
#sum of rank for first sample
sum.rank.a <-
2009 Aug 26
3
mann whitney u
Dear Sir,
I am comparing two samples using wilcox.test in R. Literature appears to describe mann whitney u test as the most appropriate test to use on my data.
is the wilcox.test function equivalent to mann-whitney u? Is there a way to gain the U-value as apposed to the W-value in R?
Thank you
2006 Aug 25
1
exact Wilcoxon signed rank test with ties and the "no longer under development" exactRanksumTests package
Dear List,
after updating the exactRanksumTests package I receive a warning that
the package is not developed any further and that one should consider
the coin package.
I don't find the signed rank test in the coin package, only the Wilcoxon
Mann Whitney U-Test. I only found a signed rank test in the stats
package (wilcox.test) which is able to calculate the exact pvalues but
unfortunately
2009 Feb 14
1
Mann Whitney test
Hi,
I have a statistical question.
To apply the Mann Whitney test to compare a pair of vectors, they must to
have the same length ?
Thanks,
Rodrigo
[[alternative HTML version deleted]]
2005 Feb 24
0
How to code a bootstrap version of the Wilcoxon-Mann-Whitney test?
Dear Stefan
I need to apply a Mann Whitney test to my data, by applying a bootstrap, in
R.
Loonkig for an answer in internet I found your question to the R mailing
list but I have not found the answer to your question.
Please, could you help me?
thank you very much in advance.
Best regards
Luciana
2007 Aug 15
0
Mann-Whitney U test discrepancies
Hi,
I do want to use the Mann-Whitney test which ranks my data and then
uses
those ranks rather than the actual data.
Here is the R code i am using:
group1<-
c(1.34,1.47,1.48,1.49,1.62,1.67,1.7,1.7,1.7,1.73,1.81,1.84,1.9,1.96,2,
2,2.19,2.29,2.29,2.41,2.41,2.46,2.5,2.6,2.8,2.8,3.07,3.3)
> group2<-
2003 Aug 26
1
Mann-Whitney U Table
Does anyone have a piece of code or know how I can use R to generate a table
of
critical values for the Mann-Whitney (aka Wilcoxon Rank Sum) test.
Ideally, I'd like a table that contains the critical values for any two
samples of size 3 through 30. I could use Monte Carlo simulation or the
normal approximation when n1 and n2 are greater than, 10, but I figured
someone may know how to
2010 Oct 29
2
wilcox.test; data type conversion?
I'm working on a quick tutorial for my students, and was planning on
using Mann-Whitney U as one of the tests.
I have the following (fake) data
grade <- c("MVG", "VG", "VG", "G", "MVG", "G", "VG", "G", "VG")
sex <- c( "male", "male", "female", "male",
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:
2009 Dec 02
5
Problem with "Cannot compute correct p-values with ties"
Dear All,
1. why did the problem happen?
2. How to solve it?
--
Best wishes,
Zhijiang Wang
--------------------------------------------
PHD Student
Room 212, Science buliding,
The International WIC Institute,
College of Computer Science and Technology,
Beijing University of Technology,
Beijing, China.
2009 Sep 07
1
Equivalence of Mann-Whitney test and Kruskal-Wallis test with k=2
Hi all,
The Kruskal-Wallis test is a generalization of the two-sample Mann-Whitney
test to *k* samples. That being the case, the Kruskal-Wallis test with *k*=2
should give an identical p-value to the Mann-Whitney test, should it not?
x1<-c(1:5)
x2<-c(6,8,9,11)
a<-wilcox.test(x1,x2,paired=FALSE)
b<-kruskal.test(list(x1,x2),paired=FALSE)
a$p.value
[1] 0.01587302
b$p.value
[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
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 <-
2017 Jun 24
0
Paired Weighted Wilcoxon test in R
Hi DC9,
As no one has answered, I would say that as both the survey package
and Professor Lumley are widely respected, that is as good as it gets.
Jim
On Fri, Jun 23, 2017 at 7:26 PM, Dreams Collector
<dreamscollector9 at gmail.com> wrote:
> Dear R-users,
>
> I?m trying to perform a non-parametric statistical pairwise comparison of two samples "x" and "y" using
2012 Nov 25
2
Finding the Degrees of Freedom in a Wilcoxon Test
Dear R-ers,
I am currently running some Wilcoxon tests in R-64.
How do I find the degrees of freedom in the output I am receiving?
> wilcox.test(good$TRUE, good$x4a, paired=FALSE)
Wilcoxon rank sum test with continuity correction
data: good$TRUE and good$x4a
W = 2455, p-value < 2.2e-16
alternative hypothesis: true location shift is not equal to 0
Thank you,
Stephen.
2013 May 30
1
wilcox_test function in coin package
Dear All,
I have two simple data samples (no groups or factors, etc.) and would just
like to compute the two-sample Wilcoxon Rank Sum test using the wilcox_test
function contained in the coin package, which is reportedly better than the
regular wilcox.test function because it performs some adjustment for ties.
Would anyone know how to craft a script to perform this task? Much
appreciated.
Janh