Displaying 20 results from an estimated 1000 matches similar to: "question for aov and kruskal"
2012 Jan 10
4
2 sample wilcox.test != kruskal.test
Hello,
I think I am right in saying that a 2 sample wilcox.test is equal to a 2
sample kruskal.test and
a 2 sample t.test is equal to a 2 sample anova. This is also stated in the
?kruskal.test man page:
The Wilcoxon rank sum test (wilcox.test) as the special case for two
samples; lm together with anova for performing one-way location analysis
under normality assumptions; with Student's t
2013 Apr 15
1
Kruskal-Wallis
Hi,
I have got two groups of samples; and for every row, I wish to calculate
Kruskal-Wallis' p-value.
In the example below, and the stars (****) show where I am struggling to
design and put things together. Any help would be appreciated.
myFile <- data.frame(Sample_1a = 1:10, Sample_1b = 2:11, Sample_1c = 3:12,
Sample_2a=4:13, Sample_2b=7:16, row.names=LETTERS[1:10])
groups <- rep
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:
2003 Nov 21
2
kruskal wallis for manova?
Hello,
Is there like the kruskal wallis test in relation to ANOVA (no
restrictions on normallity and variance homogenity) something (in R)
for MANOVA?
thanks
--
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Nordbahnhofstrasse: 1a, D-37213 Witzenhausen
Phone: 0049-(0)5542-98-1715, Fax: 0049-(0)5542-98-1713
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
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 ?
2009 Oct 14
3
post-hoc test with kruskal.test()
Dear R users,
I would like to know if there is a way in R to execute a post-hoc test
(factor levels comparison, like Tukey for ANOVA) of a non-parametric
analysis of variance with kruskal.test() function. I am comparing three
different groups. The preliminary analysis using the kruskal-wallis-test
show significance, but I still don''t know the relationship and the
significance level
2012 Jan 12
2
kruskal wallis post hoc?
Dear all,
I run a kruskal wallis test and found significant results. Then, I conducted all pairwise comparisons and found no significant results. Could anyone please give me a hint as to why this happens or redirect me towards a specific web page where I can find more info? (I used alpha=5% and made no bonferroni or other correction for the pairwise comparisons)
Thank you
Dr. Iasonas
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 Oct 11
1
How to get Mean rank for Kruskal-Wallis Test
Hello All,
I want "Ranks' Table in R as like in SPSS ouput in the given link.
http://www.statisticssolutions.com/methods-chapter/statistical-tests/kruskal-wallis-test/
Is the code is already available? Please let me know.
Thanks,
Lawrence
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
2008 Oct 16
2
Saving results of Kruskal Walis test
Hello,
I am running Kruskal-Walis test in R. When I try to save results using
write.table it gives me the following error :
Error in as.data.frame.default(x[[i]], optional = TRUE, stringsAsFactors =
stringsAsFactors) :
cannot coerce class "htest" into a data.frame
The overall code is as follows :
>data_file = read.table("~/DATA.dir/data_file.txt", header=T)
2010 Aug 03
3
Kruskal Walllis test
Hi all
My data table (g) contains a continues data column (plant.height) and other
columns (columns 8 to 57),
each with number of levels of different factors. ANOVA test was done and
the p-values were extracted
as follos:
a <- function(x) anova(lm(plant.height ~ x))$"Pr(>F)"[1]
r<- apply(g[,8:57],2,a)
If I try to do a Kruskal-Wallis test :
kw <- function(x)
2014 Jan 20
3
Creación de un bucle con test Kruskal Wallis
Hola.
Llevo poco tiempo con R y estoy atascado en un problemilla, a ver si
podéis ayudarme. Estoy trabajando con una base de datos sobre personalidad
en diferentes especies de aves. Esta base tiene datos de más de 7000
individuos y me gustaría crear un bucle mediante el cual realizar un test
de Kruskal Wallis por cada especie (quiero ver si los comportamientos son
consistentes dentro de cada
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
2008 Sep 17
2
Unexpected behaviour when testing for independence with multiple factors
Hi, I'm a new user of R. My background is Electrical Engineering, so
please bear with me if this is a silly question.
I'm trying to assess whether the results of an experiment satisfy the
hypothesis of homoscedasticity (my ultimate goal is to use ANOVA).
The result of the experiment is mean delay (dT), which depends on
three factors, topology, drift, and lambda. The first two factors are
2004 Apr 05
1
fligner.test (ctest) (PR#6739)
Full_Name: Karel Zvara
Version: 1.8.1
OS: MS Winows 2000
Submission from: (NULL) (195.113.30.163)
The test statistics of the fligner.test (ctest package) depends on the order of
cases:
> fligner.test(count~spray,data=InsectSprays)
Fligner-Killeen test for homogeneity of variances
data: count by spray
Fligner-Killeen:med chi-squared = 14.4828, df = 5, p-value =
0.01282
>
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
2008 Mar 06
1
kruskal wallis post hoc test in R
Hello,
I need nemenyi-test or any other post-hoc test for kruskal-wallis, but I
just can't find out how to implement this in R.
My data set is nitrite concentrations in four different groups which I
intend to compare. The kruskal-wallis-test showed significance, but I
still don't know between which groups these significances are.
Can anybody help me with this?
Thanks
2007 Oct 26
1
Post-hoc test for Kruskal-Wallis
Hi there,
I've got a small question :
is there any post-hoc test for Kruskal rank sum test integrated in R ?
I know that the Nemenyi test is one of the post-hoc that can be used,
but there's no (to by knowledge) R function for it.
What should I do ?
Thanks,
Etienne