Displaying 20 results from an estimated 4000 matches similar to: "A small error in mca ?"
2007 Jan 31
2
mca-graphics: all elements overlapping in the help-example for multiple correspondence analysis
Dear all,
I tried out the example in the help document for mca (the multiple correspondence analysis of the MASS package):
farms.mca <- mca(farms, abbrev=TRUE)
farms.mca
plot(farms.mca)
But the graphic that I get seems unfeasible to me: I cannot recognize the numbers (printed in black) because they are all overlapping and concealing each other. I don ?t dare using my own data, which
2000 Nov 11
2
problem using MASS corresp and mca functions
Hello,
I'm an absolute beginner with R and neophite in data analysis, so please bear
with me if I ask stupid question.
I'm trying to do a correspondence analysis using R and MASS corresp function,
but I get an error message which I'm unable to interpret:
> data(weblog)
> library(MASS)
> corresp(~ url + fromurl, data=weblog)
Error in svd(t(t(x1 * Dr) * Dc)) : error 306 in
2001 Mar 13
1
3d plots of mca() results?
Greetings.
I'm about to embark on my first big (to me at least!) R project, which
will be to write a function to plot three-dimensional multiple
correspondence analysis (mca) plots in a manner similar to
scatterplot3d(). (plot.mca() plots only two dimensions, even though
mca() will calculate more.) Before I do so, however, I would love to know
that I'm not reinventing the wheel or any
2011 Feb 05
1
different results in MASS's mca and SAS's corresp
Dear list:
I have tried MASS's mca function and SAS's PROC corresp on the
farms data (included in MASS, also used as mca's example), the
results are different:
R: mca(farms)$rs:
1 2
1 0.059296637 0.0455871427
2 0.043077902 -0.0354728795
3 0.059834286 0.0730485572
4 0.059834286 0.0730485572
5 0.012900181 -0.0503121890
6
2006 Oct 20
2
CORRESPONDENCE ANALYSIS
Enio Jelihovschi" eniojelihovs@gmail.com
Date: Fri, 20 Oct 2006 11:28:12 -0200
Subject: CORRESPONCE ANALYSIS
Dear All
I am new R user, trying to do correspondence analysis using the function mca
of the package MASS. My question is: In the following example
farms.mca <- mca(farms, abbrev = T) # Use levels as names
plot(farms.mca, cex = rep(0.7, 2), axes = F)
How can I change the
2005 Apr 07
3
analyse des correspondances multiples
bonjour,
Je voudrais faire une analyse des correspondances multiples avec R. avec
les repr?sentation graphiques correspondantes avec R.
je ne sais pas comment proc?der ..
en vour remerciant par avance
Faouzi
2007 Oct 17
3
Observations on SVD linpack errors, and a workaround
Lately I'm getting this error quite a bit:
Error in La.svd(x, nu, nv) : error code 1 from Lapack routine 'dgesdd'
I'm running R 2.5.0 on a 64 bit Intel machine running Fedora (8 I think).
Maybe the 64 bit platform is more fragile about declaring convergence.
I'm seeing way more of these errors than I ever have before.
From R-Help I see that this issue comes up from time to
2002 Nov 17
1
SVD for reducing dimensions
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Hi all, this is probably simple and I'm just doing something stupid, sorry
about that :-)
I'm trying to convert words (strings of letters) into a fairly small
dimensional space (say 10, but anything between about 5 and 50 would be ok),
which I will call a feature vector. The the distance between two words
represents the similarity of the
2008 May 16
1
Dimensions of svd V matrix
Hi,
I'm trying to do PCA on a n by p wide matrix (n < p), and I'd like to
get more principal components than there are rows. However, svd() only
returns a V matrix of with n columns (instead of p) unless the argument
nv=p is set (prcomp calls svd without setting it). Moreover, the
eigenvalues returned are always min(n, p) instead of p, even if nv is set:
> x <-
2001 Nov 16
2
DGESDD from Lapack for R-1.4.0?
Hi,
I'm just wondering if it is planned to include the Lapack
routine DGESDD (and friends) in R-1.4.0? This is faster
(supposedly by a factor of ~6 for large matrices) than
DGESVD which is currently (R-1.3.1) called by La.svd.
And if it is not in the plans yet, is there a chance it
could be? I've added it to my local version of R-1.3.1 and
so far see a factor of 4 improvement over
2000 Aug 10
1
svd error (PR#631)
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Content-Transfer-Encoding: quoted-printable
SVD-Error on
R 1.1.0
Windows 98
I get the following error applying svd on a positive definite matrix :
> sk2
[,1] [,2] [,3] [,4] [,5]
[1,] 1.0460139783 0.084356992 -2.810553e-04
2011 Sep 13
1
SVD Memory Issue
I am trying to perform Singular Value Decomposition (SVD) on a Term Document
Matrix I created using the 'tm' package. Eventually I want to do a Latent
Semantic Analysis (LSA).
There are 5677 documents with 771 terms (the DTM is 771 x 5677). When I try
to do the SVD, it runs out of memory. I am using a 12GB Dual core Machine
with Windows XP and don't think I can increase the memory
2020 May 10
2
1. character a factors (Jose Betancourt B.)
Estimados
No me resultó, describo paso a paso y adjunto base de datos
str((df[,1:2]))# evaluo el tipo de variable
salida
data.frame': 101 obs. of 2 variables:
$ alergia1 : chr "no" "no" "si" "si" ...
$ parasitismo1: chr "si" "si" "si" "si" ...
#esto es lo que quiero hacer
library(MASS)
farms.mca <-
2012 Dec 05
1
Understanding svd usage and its necessity in generalized inverse calculation
Dear R-devel:
I could use some advice about matrix calculations and steps that might
make for faster computation of generalized inverses. It appears in
some projects there is a bottleneck at the use of svd in calculation
of generalized inverses.
Here's some Rprof output I need to understand.
> summaryRprof("Amelia.out")
$by.self
self.time self.pct
2008 Apr 15
1
SVD of a variance matrix
Hello!
I suppose this is more a matrix theory question than a question on R,
but I will give it a try...
I am using La.svd to compute the singular value decomposition (SVD) of
a variance matrix, i.e., a symmetric nonnegative definite square
matrix. Let S be my variance matrix, and S = U D V' be its SVD. In my
numerical experiments I always got U = V. Is this necessarily the
case? Or I might
2001 Sep 06
1
svd and eigen
Hello List,
i need help for eigen and svd functions. I have a non-symmetric
square matrix. These matrix is not positive (some eigenvalues are
negative). I want to diagonalise these matrix. So, I use svd and
eigen and i compare the results. eigen give me the "good" eigenvalues
(positive and negative). I compare with another software and the
results are the same. BUT, when i use svd,
2003 Dec 23
1
mca
Dear All,
I want to 'impose' supplementary points to an mca plot -- using V&R MASS
library -- and I wonder if anyone had any luck. The book (4th edition) says it
can be done using predict.mca but there are no examples provided in the help
pages.
Would appreciate any help/pointers.
Thanks Marwan
btw, to Professor Ripley -- the abbrev=TRUE option for labels does not seem to
work.
2003 Apr 22
4
"LAPACK routine DGESDD gave error code -12" with Debian (PR#2822)
Dear All,
Under Debian GNU/Linux La.svd (with method = "dgesdd") sometimes gives the
error
"Error in La.svd(data, nu = 0, nv = min(nrow, ncol), method = "dgesdd") :
LAPACK routine DGESDD gave error code -12"
It seems not to depend on the data per se, but on the relationship between
numbers of rows and columns.
For example, if the number of columns is 100,
2001 Nov 02
1
Look, Watson! La.svd & ATLAS
Dear R-devel,
I had attempted to compile r-devel (dated Oct. 31, 2001) on WinNT with link
to ATLAS, with mostly success. However, when I tried the following, I got a
visit from Dr. Watson:
R : Copyright 2001, The R Development Core Team
Version 1.4.0 Under development (unstable) (2001-10-31)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under
2000 May 10
4
Q: Problems with eigen() vs. svd()
At 01:37 PM 5/10/00 +0200, ralle wrote:
>Hi,
>I have a problem understanding what is going on with eigen() for
>nonsymmetric matrices.
>Example:
>h<-rnorm(6)
>> dim(h)<-c(2,3)
>> c<-rnorm(6)
"c" is not a great choice of identifier!
>> dim(c)<-c(3,2)
>> Pi<-h %*% c
>> eigen(Pi)$values
>[1] 1.56216542 0.07147773
These could