Displaying 20 results from an estimated 500 matches similar to: "interpreting Shapiro-Wilks test result"
2005 May 03
1
multivariate Shapiro Wilks test
Hello,
I have a question about multivariate Shapiro-Wilks test.
I tried to analyze if the data I have are multivariate normal, or how
far they are from being
multivariate normal. However, any time I did
>mshapiro.test(mydata)
I get the message:
Error in solve.default(R %*% t(R), tol = 1e-18) :
system is computationally singular: reciprocal condition number
= 5.38814e-021
I tried
2002 Mar 21
1
Wilks Lamba
Hi all,
I can't figure out how to compute Wilks Lambda in a one way repeated
measure design. My matrix looks like:
> t2.m
Blank ECR ENC UEA UED
1 -0.15 0.14 0.16 0.09 0.14
2 0.30 0.08 0.14 0.14 0.14
[...]
where each row is a case and the columns are levels of one factor (named
trial):
> t2.fit <- manova(t2.m ~ 1)
> summary(t2.fit, intercept=T,
2012 Jun 19
1
Stepwise Discriminant Analysis - greedy.wilks
I don't understand which is the problem
Could you help me please?
Thanks in advance
Marta
> str(data_indiciN2)
'data.frame': 200 obs. of 36 variables:
$ gruppo: Factor w/ 2 levels "0","1": 2 2 2 2 2 2 2 2 2 2 ...
$ I001N2: num 19.32 8.22 28.35 7.24 14.7 ...
$ I002N2: num 2.92 2.54 0.11 1.6 7.12 ...
$ I003N2: num -22.362 -0.222 -19.291
2008 Apr 03
3
summary(object, test=c("Roy", "Wilks", "Pillai", ....) AND ellipse(object, center=....)
Dear All,
I would be very appreciative of your help with the following
1). I am running multivariate multiple regression through the manova() function (kindly suggested by Professor Venables) and getting two different answers for test=c("Wilks","Roy","Pillai") and tests=c("Wilks","Roy",'"Pillai") as shown below. In the
2010 Mar 23
1
information module Wilks' lambda criterion
Hi everybody,
I was wondering if you can help me about a module. In fact, I'm looking for
a package or module about Wilks' lambda criterion in R environment. I didn't
find it in R website (
http://cran.cict.fr/web/packages/index.html#available-packages-W or
http://search.cpan.org/faq.html).
If this module exists, could you show me the command line.
Thank you very much for your help,
2008 Jan 13
1
Shapiro-Wilk
What is the formula used in Shapiro-Wilk Statistic?
Thanks
Eduardo (S?o Paulo/ Brazil)
2008 Jul 14
0
"Reasonable doubt" - was "Re: shapiro wilk normality test"
>>> Ted Harding <Ted.Harding at manchester.ac.uk> 14/07/2008 00:16 >>>
>said:
>What constitutes "reasonable doubt" can become a very interesting
>question, but there are some crimes for which it has a definite
>statistical interpretation
Warning for potential courtgoers: "reasonable doubt" NEVER has a direct
statistical interpretation in a
1999 Nov 04
1
shapiro wilk
I'm pretty new to R and are trying to do some reliable normality
testing... but, can't find the Shapiro Wilk test in R Does some
experienced user have such a function that will be wanting to share with
me? Or there is maybe some other way to get hte Shapiro Wilk test
done... I'll appreciate any hint on this,
Thanks
--
***********************
Horacio Samaniego
Dep. Ecologia
P.
2000 Sep 25
1
Interpretation of Shapiro-Wilk
Can anybody tell me the exact meaning of the $statistic and $p.value
calculated by shapiro.test? Unfortunately it is not covered in my few
text books, and I cannot find the explanation in the R documentatiom or
on-line.
If I have a test statistic, T, which is Normally distributed with mean=m
and sd=s under the null hypothesis, then I can convert T to a p-value
(one-sided) using:
p <- pnorm(T,
2010 Feb 18
1
Shapiro-Wilk test problem
Hi everybody,
Does anyone know what problem may be with this test.
I am applying 5 different normality tests and use p-values for them, but for
some reason S-W gives me NA, while sample size is 100.
Any ideas?
Thanks a lot!
[[alternative HTML version deleted]]
2003 Mar 17
0
Built-In Wilks Lambda for lda?
Hello,
using the lda-method from MASS-package I was wondering whether there is
a built-in method for figuring out Wilks' Lambda?
Searching the Web I found in the r-help archive a thread form june 2002,
but it didn't help me.
I understand I can use manova and its summary-method to get Wilks' Lambda
on the screen, but I don't see the connection to lda from MASS.
Or does
2010 Apr 13
0
Wilks lamda and single discriminant function
Dear R-users,
I'm wondering how to obtain Wilks-lambda values when discriminant
analyses have only one discriminant function (i.e. 2 categories to
discriminate between).
The use of manova(predictions~groups, test="Wilks") asks for multiple
response and the use of anova(lm(predictions~groups), test="Wilks")
simply does not consider the last term.
(The alternative
2012 Jun 19
0
greedy.wilks
I have used the greedy.wilks to stepwise discriminant analysis, but it
doesn't work with my dataset.
I don't understand which is the problem
Could you help me please?
Thanks in advance
Marta
> str(data_indiciN2)
'data.frame': 200 obs. of 36 variables:
$ gruppo: Factor w/ 2 levels "0","1": 2 2 2 2 2 2 2 2 2 2 ...
$ I001N2: num 19.32 8.22 28.35 7.24
2002 Mar 30
0
Wilks' Lambda for lda?!
Hello!
As I remember there were questions concerning wilks' lambda lately.
But I lost those e-mails. So I dare ask again.
Is there a way of calculating wilks' lambda for lda?
Christoph.
--
Christoph Lange clange at epost.de
Verhaltensbiologie, FU Berlin 838-55068
Haderslebener Str. 9, 12163 Berlin
2012 Apr 04
1
Shapiro-Wilk cpoefficients: 2 Qs
Greetings!
I want to have the coefficients that R uses in shapiro.test()
for the Shapiro-Wilk test for a prticular sample size, i.e.
the a[i] in
W = Sum(a[i]*x[i])/(Sum(x[i] - mean(x))^2)
(where the x[i] are sorted). Two questions:
Q1:
Is there a readymade R function from which I can extract these?
Q2:
I was wondering if I might be able to modify the code for the
function shapiro.test() so
2005 Nov 09
1
Problems with Shapiro Wilk's test of normality.
Hi,
I am trying to create a table with information from Shapiro Wilk's
test of normality.
However, it fails due to lack of sample size, it says, but the way I
see it, this is not a problem.
(See the table of sample sizes (almost) at the bottom).
Applying a different function using a similar ftable call is not a
problem (See the bottom table).
This is R 2.1.0 on Linux (Gentoo).
/Fredrik
2001 Jul 02
2
Shapiro-Wilk test
Hi,
does the shapiro wilk test in R-1.3.0 work correctly? Maybe it does, but can
anybody tell me why the following sample doesn't give "W = 1" and
"p-value = 1":
R> x<-1:9/10;x
[1] 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
R> shapiro.test(qnorm(x))
Shapiro-Wilk normality test
data: qnorm(x)
W = 0.9925, p-value = 0.9986
I can't imagine a sample being
2007 Jun 19
2
How to compute Wilk's Lambda
Dear helpeRs,
the following data set comes from Johnson/Wichern: Applied Multivariate
Statistical Analysis, 6th ed, pp. 304-306.
/X <- structure(c(9, 6, 9, 3, 2, 7), .Dim = as.integer(c(3, 2)))
Y <- structure(c(0, 2, 4, 0), .Dim = as.integer(c(2, 2)))
Z <- structure(c(3, 1, 2, 8, 9, 7), .Dim = as.integer(c(3, 2)))/
I would like to compute Wilk's Lambda in R, which I know is 0.0385.
2003 Jul 16
1
The two chisq.test p values differ when the contingency table is transposed! (PR#3486)
Full_Name: Tao Shi
Version: 1.7.0
OS: Windows XP Professional
Submission from: (NULL) (149.142.163.65)
> x
[,1] [,2]
[1,] 149 151
[2,] 1 8
> c2x<-chisq.test(x, simulate.p.value=T, B=100000)$p.value
> for(i in (1:20)){c2x<-c(c2x,chisq.test(x,
simulate.p.value=T,B=100000)$p.value)}
> c2tx<-chisq.test(t(x), simulate.p.value=T, B=100000)$p.value
> for(i in
2013 Apr 05
2
How to perform a grouped shapiro wilk test on dataframe
Hello,
I was wandering if it is possible to perform on a dataframe called 'all' a
shapiro wilk normality test for COUNTS by variable Group
ACTIVITY? Could it be done using plyer? I saw an eg that applies to an
array but not to a dataframe:
lapply(split(dataset1$Height,dataset1$Group),shapiro.test)
Any thoughts would be much appreciated.
My dataframe is in shape:
dat ACTIVIT