Displaying 20 results from an estimated 9000 matches similar to: "effect sizes for Wilcoxon tests"
2008 Jan 26
1
How to apply the wilcox_test function to subsets ?
Dear R-forumites,
I want to apply a Wilcoxon test on subsets of the data frame mydata,
splitted using the myindice variable. When I send :
wilcoxtest <- by(mydata, mydata$myindice, function(x)
{wilcox_test(x$value~x$fact)})
I get :
Error in eval(expr, envir, enclos) : object "x" not found
whereas
wilcoxtest <- by(mydata, mydata$myindice, function(x)
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
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)?
2010 Aug 17
3
Weird differing results when using the Wilcoxon-test
Hi,
I became a little bit confused when working with the Wilcoxon test in R.
As far as I understood, there are mainly two versions:
1) wilcox.test{stats}, which is the default and an approximation, especially,
when ties are involved
2) wilcox_test{coin}, which does calculate the distribution _exactly_ even,
with ties.
I have the following scenario:
#---BeginCode---
# big example
size = 60
2000 Dec 18
2
Help: StatXact
Help needed!
Has anyone access to StatXact? I just hacked exact two-sided p-values for
rank tests (for package exactDistr, which will move to CRAN/contrib as
exactRankTests soon ;-) and would like to compare the results of my
implementation to that of StatXact. Could someone please calculate the
exact one-sided (both greater and less) and two-sided p-values?
# Data from the StatXact-4 manual,
2006 Sep 29
1
Wilcoxon Rank test of Package Coin
Hi,
I am running the following example which can be found on page 12 of the pdf file of COIN package
wt<-wilcox_test(pd~age,data=water_transfer,distribution="exact", conf.int=TRUE)
"wt" actually contains the estimate of difference in location and the confidence interval of it. I am just wondering how can I extract these values? From the examples, I understand that the
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
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
2006 Oct 05
1
The W statistic in wilcox.exact
Does anyone know why wilcox.exact gives W-statistic 6 instead of 12 as indicated below.
12 is the rank sum of group 0 of x, which is the linear statistic computed by wilcox_test.
y<-c(1,2,3,4,5)
x<-c(1,1,0,0,0)
(a) wilcox.exact
wilcox.exact(y~x)
Exact Wilcoxon rank sum test
data: y by x
W = 6, p-value = 0.2
alternative hypothesis: true mu is not equal to 0
(b) wilcox_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 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
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:
2013 Sep 16
3
b
Estimado José, por lo que estuve mirando aqui
https://en.wikipedia.org/wiki/Wilcoxon_signed-rank_test, en ?wilcox.test
y en libros de papel ... los datos deben cumplir ciertas condiciones,
quiza la mas restrictiva es que sean pareados ... si no lo son, quiza
esta variante del test es mas apropiada:
https://en.wikipedia.org/wiki/Mann-Whitney-Wilcoxon_test
la que en R se aplica usando el mismo
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
2003 Jun 11
1
qwilcox
The function 'wilcox.test' in R and S gives (almost) identical results (see
below). 'qwilcox' however, does not:
> qwilcox(p,5,5)
p: 0.025 0.975
--------------------
R> 3 22
S> 18 37
I originally wanted to ask a questions, but then I found the answer. Given
the confusion I run into, I wonder if this experience is worth reporting.
The
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 Apr 12
2
The three routines in R that calculate the wilcoxon signed-rank test give different p-values.......which is correct?
I have a question concerning the Wilcoxon signed-rank test, and
specifically, which R subroutine I should use for my particular dataset.
There are three different commands in R (that I'm aware of) that calculate
the Wilcoxon signed-rank test; wilcox.test, wilcox.exact, and
wilcoxsign_test. When I run the three commands on the same dataset, I get
different p-values. I'm hoping that
2001 Apr 05
2
CI for wilcoxon test (PR#895)
Full_Name: Marketa Kylouskova
Version: 1.2.1
OS: Windows
Submission from: (NULL) (147.231.7.2)
Hi,
I believe there is a bug in the extension of wilcox.test, namely in
determination of confidence intervals. I concentrated on the two-sample test
only. I examined and tested its performance on this working data set:
x<-rnorm(10,3,1) # So I have two samples, I will test whether
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 Mar 02
3
Help with Wilcoxon Test
Hi
I have 2 sets of data that I want to do a Wilcoxon test on. They are of the same dimension. One has 4 zero values and the other has 5.
> dim(SampA)
[1] 1 10
> dim(SampV)
[1] 1 10
I get the folowing error
Error in wilcox.test.default(SampA, SampV, na.rm = TRUE, paired = FALSE, :
'x' must be numeric
I am using the function
wilcox.test(SampA, SampV, na.rm=TRUE,