Displaying 20 results from an estimated 800 matches similar to: "dudi.pca behaviour and discrimin"
2009 Jan 24
1
Help with dudi.pca
Dear R-helpers,
I have two data frames, op and em4:
> str(op)
'data.frame': 37 obs. of 5 variables:
$ m : num 0.202 0.336 0.122 0.139 0.14 ...
$ lln : num 0.798 0.643 0.863 0.835 0.823 ...
$ rrn : num 0.789 0.702 0.894 0.895 0.923 ...
$ asym2: num 0.177 0.304 0.108 0.187 0.274 ...
$ asym3: num 0.0755 0.0975 0.0818 0.0651 0.13 ...
> str(rownames(op))
chr
2001 Nov 05
1
Problem to transfer Splus functions
Hello
I would like to transfer some Splus functions in R.
But I have a problem first about this assignation in Splus :
xnom <- deparse(substitute(x))
I am a bad programmer : I don't understand the R help
How to modify these functions ?
Thank you very much for your help
Here are the four functions and a data test
2013 Aug 27
2
Encontrar las variables más importantes en componentes principales
Hola compañeros de la lista. Qué tal.
Tengo un análisis de componentes principales, en el que se evalúan
aproximadamente 1000 variables. Usando la función dudi.pca e
inertia.dudi obtengo una cantidad de información sobre la influencia de
las variables sobre los dos componentes principales. Me gustaría saber
si existe alguna función que sobre esta información me arrojara la lista
de
2013 Aug 29
0
Encontrar las variables más importantes en componentes principales
Hola Argel,
Puedes encontrar un par de ejemplos que cómo conseguir una valoración
(qualitativa y cuantitativa) de la contribución de cada variable a cada
componente principal, en el libro "Exploratory Multivariate Analysis by
Example Using R".
Este libro está basado en la librería "FactoMineR".
Los ejemplos están en el capítulo primero.
No he mirado como se haría esto con
2011 Nov 05
1
testing significance of axis loadings from multivariate dudi.mix
Hi all
I?m trying to tests the significance of loadings from a ordination of 46 variables
(caategorical, ordinal and nominal). I used dudi.mix from ade4 for the ordination. A
years ago Jari Oksanen wrote this script implementing Peres-Neto et al. 2003 (Ecology)
bootstraping method:
netoboot <- function (x, permutations=1000, ...)
{
pcnull <- princomp(x, cor = TRUE, ...)
res
2013 Aug 29
1
Resumen de R-help-es, Vol 54, Envío 22
Hola! No he podido consultar la doc. del paquete ade4, algo debe estar caído en CRAN ahora mismo.
Dos cosas sobre la metodología -aun desconociendo los detalles de cómo lo hace ade4:
El output de un PCA, los "pesos" de cada variable en las dimensiones de los componentes se interpretan como correlaciones, a mayor valor absoluto mayor asociación variable-componente. Ahora, como tales
2005 Mar 14
1
Significance of Principal Coordinates
Dear all,
I was looking for methods in R that allow assessing the number of
significant principal coordinates. Unfortunatly I was not very
successful. I expanded my search to the web and Current Contents,
however, the information I found is very limited.
Therefore, I tried to write code for doing a randomization. I would
highly appriciate if somebody could comment on the following approach.
2006 May 03
2
mca id numbers
Is it possible to make disappear the id numbers from scatter.dudi (mc
analysis) ?
a <- as.factor(c(1, 2, 3, 2, 1))
b <- as.factor(c(3, 2, 3, 1, 1))
x <- as.factor(c(1, 2, 2, 1, 3))
y <- as.factor(c(2, 2, 3, 1, 1))
dat <- data.frame(a=a, b=b,x=x,y=y)
summary(dat)
dat
require(ade4)
dat.acm <- dudi.acm(dat, scann = FALSE, nf = 2)
scatter.dudi(dat.acm)
Thank you very much !
2012 Nov 18
1
help interpreting dudi.pco
I am working on morphometry of hairs and want to see if selected variables
are giving significantly distinct groups.
I am new to both R and principal coordinate analysis. Scatter plot is
showing distinct groups but i dont know how to refine the analysis and
interprete it.
[[alternative HTML version deleted]]
2005 May 16
1
graphic
Hi,
poids taille fumeur sexe sport etat
85 184 oui homme 1 malade
65 175 oui homme 1 malade
74 180 oui homme 2 gueri
79 175 oui homme 2 malade
71 165 non homme 3 gueri
80 185 non homme 3 gueri
75 180 non homme 4 malade
69 155 non homme 4 malade
74 168 oui
2012 Aug 03
2
how to identify values from a column of a dataframe, and insert them in other data.frame with the corresponding id?
Hello,
I’d like to do next, see if you could help me please:
I have a csv called “datuak” with a id called “calee_id” and a colunm called “poids”.
I have another csv called “datuak2” with the same id called “calee_id”, (although there are “calee_id” that are in “datuak” but not in “datuak2” and inverse), and a column called “kg_totales” in which the values are repeteated for each calee_id
2005 Jan 08
0
cmdscale problem
Dear R developers,
there appears to be a small problem with function cmdscale: for
non-Euclidean distance matrices, using option add=FALSE (the default),
cmdscale misses the smallest eigenvalue. This affects GOF statistic g.1
(See Mardia, Kent + Bibby (1979): Multivariate Analysis, eq. (14.4.7).
The corresponding formula in Cox + Cox (2001): Multidimensional Scaling,
2nd ed., p 38, would
2010 Feb 18
1
R-commands for MDS
Hello
I am using the following command but not able to text the values on the graph can
someone please make suggestions for improvement
#here is the command
loc_mds <- cmdscale(dist.r, k = 7, eig = TRUE)
loc_mds$eig
sum(abs(loc_mds$eig[1:2]))/sum(abs(loc_mds$eig))
sum((loc_mds$eig[1:2])^2)/sum((loc_mds$eig)^2)
x <-loc_mds$points[,1]
y <-loc_mds$points[,2]
plot(x, y,
2005 Nov 11
1
Snow parLapply
Dear R-user,
I am trying to use the function 'parLapply' from the 'snow' package
which is supposed to work the same wys as 'lapply' but for a
parallelized cluster of computers. The function I am trying to call in
parallel is 'dudi.pca' (from the 'ade4' package) which performs
principal component analyses. When I call this function on a list of
2003 Jun 03
3
lda: how to get the eigenvalues
Dear R-users
How can I get the eigenvalues out of an lda analysis?
thanks a lot
christoph
--
Christoph Lehmann <christoph.lehmann at gmx.ch>
2005 Dec 04
1
Understanding nonlinear optimization and Rosenbrock's banana valley function?
GENERAL REFERENCE ON NONLINEAR OPTIMIZATION?
What are your favorite references on nonlinear optimization? I like
Bates and Watts (1988) Nonlinear Regression Analysis and Its
Applications (Wiley), especially for its key insights regarding
parameter effects vs. intrinsic curvature. Before I spent time and
money on several of the refences cited on the help pages for "optim",
2012 Sep 24
0
(no subject)
http://perdre-du-poids-rapidement.com/wp-content/plugins/instantupgrade/google.html?orqm=ns.psml&sg=fth.ytf&oeo=magd">http://perdre-du-poids-rapidement.com/wp-content/plugins/instantupgrade/google.html?orqm=ns.psml&sg=fth.ytf&oeo=magd
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2008 Jan 05
2
Cumulative sum of vector
Hi,
Maybe I have not been looking in the right spot, but, I have not been
able to fine a command to automatically calculate the running
cumulative sum of a vector. Is there such a command?
Example of current code:
> eig$values
[1] 678.365651 6.769697 2.853783
> prop<-eig$values/sum(eig$values)
> prop
[1] 0.986012163 0.009839832 0.004148005
>
2012 Mar 15
0
PCA R
Hello can anyone help,
I have been running the following script to obtain a PCA plot but the end result is rather disappointing as the points are very very small and there are no titles etc
geochemdata<-read.csv(file.choose(),header=TRUE)
names(geochemdata)
library(vegan)
bstick<-function(n, tot.var=1) rev(cumsum(tot.var/n:1)/n)
geopca<-rda(geochemdata, scale=TRUE)
geopca
2013 Oct 02
0
Análisis de componentes principales con ade4 y FactoMineR
Efectivamente. Puedes cambiar el signo de todos los valores de la
segunda componente, por ejemplo al hacer un gráfico de dispersión.
No creo que se pueda hacer directamente en la función.
Saludos
Francesc
El 01/10/13 17:53, Argel Gastélum Arellánez ha escrit:
> Hola Francesc, muchas gracias por tu respuesta.
>
> Entonces, si quisiera que las gráficas de los resultados de