Displaying 20 results from an estimated 4000 matches similar to: "left eigenvector"
2004 Jul 13
3
plotting a table together with graphs
Check out textplot in the gregmisc package ...
Federico Calboli <f.calboli@ucl.ac.uk>
Sent by: r-help-bounces@stat.math.ethz.ch
07/13/2004 12:06 PM
Please respond to f.calboli
To: r-help <r-help@stat.math.ethz.ch>
cc:
Subject: [R] plotting a table together with graphs
Dear All,
I would like to ask how to add a table to a
2004 Jul 15
1
how to upload [forwarded]
[ This was posted to the R-packages list (which I moderate),
but definitely doesn't belong there. Martin Maechler
]
------- start of forwarded message -------
From: Federico Calboli <f.calboli at ucl.ac.uk>
To: r-packages at stat.math.ethz.ch
Subject: how to upload
Date: 15 Jul 2004 18:30:26 +0100
Dear All,
I just finished a add on lib called Malmig, to calculate Malecot
2004 May 21
2
Sum of Squares in a lme model
Dear All,
I would like to ask how to get the Sum of Squares from fitted lme model.
I appreciate that lme maximises the likelihood (or REML) and uses
likelihood ratio tests, but I just fail why I could not get the SS if I
want them. I could use lm to calculate them, but it looks quite
pointless to fit a second (and wrong in a way) model for something so
trivial.
I know that the issue has been
2004 Feb 23
2
plot(my.procrustes.model) from library {vegan}
Dear All,
I would like to ask how to customize the graph corresponding to a
procrustes analysis.
I have to distance matrices, that I transform to two set of coordinates
by means of muti dimensional scaling:
library(mva)
c1<-cmdscale(mat.dist1)
c2<-cmdscale(mat.dist2)
I vant to rotate c2 on c1, and I use the "procrustes" analysis from the
{vegan} library.
library(vegan)
2004 Apr 07
1
problems loading package "nlme" in Debian Sid
Dear All,
I apologize if the following has been already asked, but I could not
find anything in the archives.
I am running Debian Sid (on an Athlon XP), with R 1.8.1.cvs.20040307-1
(it describes itself as "R 1.9.0 experimental" when I fire R up) and I
am unable to load the library "nlme" (I apt-getted r-recommended, so the
library is on the system)
>library(nlme)
Error in
2004 Jan 20
4
matrix exponential: M^0
> -----Original Message-----
> From: Federico Calboli
> Sent: Tuesday, January 20, 2004 5:40 PM
> To: r-help
> Subject: [R] matrix exponential: M^0
>
> I would like to ask why the zeroeth power of a matrix gives me a matrix
> of ones rather than the identity matrix:
>
> > D<-rbind(c(0,0,0),c(0,0,0),c(0,0,0))
> > D<-as.matrix(D)
> > D
>
2004 Feb 26
2
Multidimensional scaling and distance matrices
Dear All,
I am in the somewhat unfortunate position of having to reproduce the
results previously obtained from (non-metric?) MDS on a "kinship" matrix
using Statistica. A kinship matrix measures affinity between groups, and
has its maximum values on the diagonal.
Apparently, starting with a nxn kinship matrix, all it was needed to do
was to feed it to Statistica flagging that the
2004 Mar 12
3
R-business case
Dear all,
I am putting together a business case for R and I would like to know if
there exist statistics on the distribution of R in academia, research
and commercial institutions. The same information about S-plus would be
welcome. Please reply only if you have consistent and certain information.
Thank you very much, giovanni
2003 Dec 02
1
question regarding variance components
I am using a two-factor ANOVA model with random factor effects including
the interaction, i.e. the factors are crossed. I would like to be able to
generate all four variance components along with approximate confidence
intervals using the NLME package. However, I do not know how to specify
the random option because of two problems. First, I do not know how to
enter the interaction term into the
2004 May 18
1
1-way anova, nested model
Dear all,
We compared the gene expression level in two conditions: high (H) and low (L), using real-time PCR. We had 3 samples of each condition, and we quantified each sample twice (i.e. a technical replication).
Our data looks like:
H1 H1 H2 H2 H3 H3 L1 L1 L2 L2 L3 L3
We want to test if the level in H vs L is significantly different. I would like to use ANOVA and I guess a nested model with
2003 Dec 09
2
p-value from chisq.test working strangely on 1.8.1
Hello everybody,
I'm seeing some strange behavior on R 1.8.1 on Intel/Linux compiled
with gcc 3.2.2. The p-value calculated from the chisq.test function is
incorrect for some input values:
> chisq.test(matrix(c(0, 1, 1, 12555), 2, 2), simulate.p.value=TRUE)
Pearson's Chi-squared test with simulated p-value (based on 2000
replicates)
data: matrix(c(0, 1, 1,
2004 Jan 20
0
Matrix exponential
How about this:
> expm
function(x,pow=2)
{
xd <- diag((eigen(x)$values^pow))
xm <- eigen(x)$vector %*% xd %*% t(eigen(x)$vector)
return(xm)
}
> xa
[,1] [,2]
[1,] 2 1
[2,] 1 3
> expm(xa,pow=3)
[,1] [,2]
[1,] 15 20
[2,] 20 35
> xa %*% xa %*% xa
[,1] [,2]
[1,] 15 20
[2,] 20 35
>
From: Federico Calboli <f.calboli at ucl.ac.uk>
2004 May 18
3
Debian & R
I use linux debian testing for which the latest debianized version of R
is 1.8.1. Therefore I installed:
r-base-core_1.8.1-0.cran.1_i386.deb
r-base-dev_1.8.1-0.cran.1_all.deb
r-base-html_1.8.1-0.cran.1_all.deb
r-base-latex_1.8.1-0.cran.1_all.deb
r-base_1.8.1-0.cran.1_all.deb
r-doc-html_1.8.1-0.cran.1_all.deb
r-doc-info_1.8.1-0.cran.1_all.deb
2004 Jan 07
0
malecot migration matrix
Dear All,
I would like to ask if there is any package that would calculate Malecot
migration matrix (or the Imaizumi or Pena implementations of the MMM). I
did a site-wide search, and went trough the table of contents of a
number of packages that seemed promising, but with no luck.
Regards,
Federico Calboli
--
=================================
Federico C. F. Calboli
PLEASE NOTE NEW
2004 Aug 01
0
phylogenetic trees calculation
Dear all,
I would like to ask you the following:
I have data about different manuscripts, together with data about the
presence/absence of copying errors, in the days when manuscript were
really manuscripts. I would ideally like to use the data to draw a
phylogenetic tree, so that I can infer which ms was copied from which.
The error presence/absence is coded in binary format. The plan is to use
2012 Apr 27
2
find the eigenvector corresponding to the largest eigenvalue
Hi,
If I use the eigen() function to find the eigenvalues of a matrix, how can I find the eigenvector corresponding to the largest eigen value?
Thanks!
[[alternative HTML version deleted]]
2005 Jan 29
1
Bootstrapped eigenvector
Hello alls,
I found in the literature a technique that has been evaluated as one of the
more robust to assess statistically the significance of the loadings in a
PCA: bootstrapping the eigenvector (Jackson, Ecology 1993, 74: 2204-2214;
Peres-Neto and al. 2003. Ecology 84:2347-2363). However, I'm not able to
transform by myself the following steps into a R program, yet?
Can someone could help
2009 Jan 19
3
bootstrapped eigenvector method following prcomp
G'Day R users!
Following an ordination using prcomp, I'd like to test which variables
singnificantly contribute to a principal component. There is a method
suggested by Peres-Neto and al. 2003. Ecology 84:2347-2363 called
"bootstrapped eigenvector". It was asked for that in this forum in
January 2005 by J?r?me Lema?tre:
"1) Resample 1000 times with replacement entire
2009 Apr 23
1
the definition of eigenvector in R
Dear All
i have a little puzzle about eigenvector in the R.
As we know that the eigenvector can be displayed on several form.
For example
A=matrix(c(1,2,4,3),2,2)
if we want to get the eigenvalue and eigenvector, the code followed
eigen(A)
$values
[1] 5 -1
$vectors
[,1] [,2]
[1,] -0.7071068 -0.8944272
[2,] -0.7071068 0.4472136
however, we also can calculate the vector matrix
2009 Apr 24
1
the puzzle of eigenvector and eigenvalue
Dear all
I am so glad the R can provide the efficient calculate about
eigenvector and eigenvalue.
However, i have some puzzle about the procedure of eigen.
Fristly, what kind of procedue does the R utilize such that the eigen
are obtained?
For example, A=matrix(c(1,2,4,3),2,2)
we can define the eigenvalue lamda, such as
det | 1-lamda 4 | =0
| 2 3-lamda |
then