Displaying 20 results from an estimated 1000 matches similar to: "npmc and data.frame problems"
2006 Mar 04
1
Npmc for doing post-hoc after Kruskal
I followed the threads that enquired about doing post-hoc tests after doing
Kruskal testing. It took me to npmc. But npmc is giving an output I do not
understand.
I noticed a thread entitled "npmc function: 'x' must be atomic" but there
never appeared to be a resolution.
> npmc(npmcinput)
Error in sort(unique.default(x), na.last = TRUE) :
'x' must be atomic
2004 Apr 26
0
npmc problem?
Hi,
I recently tried to conduct non-parametric multiple comparison with
npmc package, and encountered some problem; sometimes it stopped with
following error.
Error in uniroot(f = function(arg) p - z.dist(arg, corr = corr, df =
df, :
f() values at end points not of opposite sign
Although I'm not quite sure about calculation of z.quaintile in npmc.R,
it seems increment of
2010 Jun 14
2
NPMC
HI,
I am a new user of R and want to analyse some data using npmc. My data have
several levels of factor (Site, Year and Season) and several variable
(Percentages).
I have tried to use npmc but I always get an error message. My data are in a
table following this example:
Site YEar Season Var1 Var2 ....
A 2009 Dry 10 56
B ........
here is the error
2011 Feb 21
2
NPMC - replacement has 0 rows (multiple comparisons)
Hi folks, sorry if this has been answered before, I searched long and hard
before deciding to make a thread.
I'm trying to include multiple variables in a non-parametric analysis
(hah!). So far what I've managed to figure out is that the NPMC package from
CRAN MIGHT be able to do what I need, but I can't get it to.
First I created a dataset as NPMC calls for.
> Ind=Individual
2011 Mar 20
2
Problems with package npmc
Hi there,
I am having a problem with package npmc. If I use the included datasets
(brain, kronen) everything is fine, but if I try and use my dataset I
receive an error message:
Error in probval.GenzBretz(algorithm, n, df, lower, upper, infin, corr, :
NAs in foreign function call (arg 2)
In addition: Warning message:
In probval.GenzBretz(algorithm, n, df, lower, upper, infin, corr, :
NAs
2004 Jun 22
1
npmc function: 'x' must be atomic
Hi,
I'm having trouble getting the function `npmc' working. I have a
2 column 30 row table called `mydata':
> npmc(mydata, df=2, alpha=0.05)
Error in sort(unique.default(x), na.last = TRUE) :
`x' must be atomic
> is.atomic(mydata)
[1] TRUE
Is there anything I have overlooked? Am I invoking the function
correctly? I wasn't able to find any hints in the archives
2005 Oct 19
3
npmc package
Hi
Does anyone know where is the package: npmc (Nonparametric Multiple
Comparisons).
I found the reference on R Site Search, but not the package itself on
CRAN as suggested.
Thanks
Mauricio
2013 Jul 10
1
Kruskal.test
Hi,
Please dput() your example dataset.
dat1<- read.table(text="a?? a?? a?? a??? a??? b?? b??? b??? c??? c?? c??? c
2? 4??? 5?? 2??? 7??? 2?? 2??? 6??? 3??? 7?? 9??? 3
3? 3?? 4?? 1???? 6??? 8?? 1??? 3??? 5??? 2??? 6??? 3",sep="",header=FALSE,stringsAsFactors=FALSE)
library(reshape)
?dat2<-melt(as.data.frame(t(dat1)),id.var="V1")[,-2]
2003 Jan 30
1
Kruskal-Wallis, Friedman tests and Tukey HSD
Dear all
Is there any way of doing a Tukey HSD post-hoc test after a Kruskal-
Wallis or Friedman rank sum test (in the ctest package)?
Thanks in advance,
Albertus
Dr. Albertus J. Smit
Department of Botany
University of Cape Town
Private Bag Rondebosch
7700
South Africa
Tel. +27 21 689 3032
2010 Feb 24
1
extracting results from wilcox_test (package::coin)
Recently, I ran a series of Kruskal-Wallace tests [kruskal.test()] using by()
to group by site Output is a list:
>Herb.KW
Herb.df$ID: 10-1
Kruskal-Wallis rank sum test
data: Indicator_Rating by Year
Kruskal-Wallis chi-squared = 15.24, df = 7, p-value = 0.03302
-----------------------------------------------------------------------------------------------------
Herb.df$ID: 18-1
2004 Apr 25
2
nonparametric multiple sample comparison
Hello all,
Here goes one of my first functions.
I want to make a nonparametric multiple sample comparison with unequal sample
sizes (see Zar?s Biostatistical Analysis, 3rd. Ed., pg. 201 Example 10.11, pg.
288 Example 11.10). In the real world, I want to compare samples of fish
length captured with different fishing gears.
After using the Kruskal-Wallis test I want to check the differences
2008 Aug 21
1
Kruskal.test() on lists
Hi,
I am trying to do a kruskal wallis test on two lists, fVisited and cSN:
fVisited[[1]]
[1] 0.17097623 0.30376141 0.17577266 0.14951855 0.03959753 0.08096217 0.05744888 0.02196257....
....
cSN[[1]]
[1] 0.08557303 0.36477791 0.19601252 0.12981040 0.05351320 0.10385542 0.03539577 0.03106175....
So if I just want to do a test on just one of the entries this is simple enough:
2013 Jul 09
1
Kruskal.test
Hi,
?kruskal.test()
?a<- c(2,4,5,2,7)
?b<- c(2,2,6)
?c<- c(3,7,9,3)
?kruskal.test(list(a,b,c))
#
?#? Kruskal-Wallis rank sum test
#
#data:? list(a, b, c)
#Kruskal-Wallis chi-squared = 2.003, df = 2, p-value = 0.3673
A.K.
Hi
I need an expression in R to apply a kruskal.test to this data (for example).
a ? a ? a ? a ? ?a ? ?b ? b ? ?b ? ?c ? ?c ? c ? ?c
2 ?4 ? ?5 ? 2 ? ?7 ? ?2 ? 2 ?
2008 Oct 22
1
Saving kruskal wallis p-values
Hi everyone,
I am working on analyzing spectra which requires hundreds of kruskal wallis
tests to be performed. Once significant results are found post tests are
performed ect. My questions are: how do I perform all these kw tests and
save just the pvalues in a table? Is there anyway to have R automatically
perform post tests if a result of p<0.05 is found? Currently when I run the
test
2010 Oct 27
1
(no subject)
I am interested in using "multcompLetters" after running "kruskalmc" but
I'm a newbie and I'm not having luck figuring it out. I can run "kruskalmc" just fine,
but after studying the documentation for "multcompletters" for a long time,
I cannot figure out how to make it work. Any ideas? R input is below
>
>> #here is my data set
>>
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]
2010 Feb 18
2
Extracting values from a list
I have run a kruskal.test() using the by() function, which returns a list of
results like the following (subset of results):
Herb.df$ID: 4-2
Kruskal-Wallis chi-squared = 18.93, df = 7, p-value = 0.00841
--------------------------------------------------------------------
Herb.df$ID: 44-1
Kruskal-Wallis chi-squared = 4.43, df = 6, p-value = 0.6187
So then, how do extract a vector
2012 Mar 26
0
Different result with "kruskal.test" and post-hoc analysis with Nemenyi-Damico-Wolfe-Dunn test implemented in the help page for oneway_test in the coin package that uses multcomp
Dear Researchers,
Sorry for this email but I am not a statistician, and for this I have this
problem to understand. Thanks in Advance for help and suggestions.
Gianni
I have 21 classes (00, 01, 02, 04, ....,020) with different length. I did a
kruskal wall test in R with the following code
kruskal.test(m.class.l, m.class.length.lf)
Kruskal-Wallis rank sum test
data: m.class.l and
2012 Jun 11
1
Kruskal Wallis Post hoc
Hi, I have searched and found a response to a question similar to mine but
when I tried the code, R says it's not an actual function so I thought I'd
ask here.
http://r.789695.n4.nabble.com/file/n4633035/Cookies.csv Cookies.csv
I have attached the data I am using. I am trying to look at two things: how
moisture content changes over time, and how it changes along the length of a
log
2012 Aug 03
1
Multiple Comparisons-Kruskal-Wallis-Test: kruskal{agricolae} and kruskalmc{pgirmess} don't yield the same results although they should do (?)
Hi there,
I am doing multiple comparisons for data that is not normally distributed.
For this purpose I tried both functions kruskal{agricolae} and
kruskalmc{pgirmess}. It confuses me that these functions do not yield the
same results although they are doing the same thing, don't they? Can anyone
tell my why this happens and which function I can trust?
kruskalmc() tells me that there are no