Displaying 20 results from an estimated 30000 matches similar to: "Linear Discriminant Analysis"
2013 Nov 10
0
Mark each group centroid in a linear discriminant analysis plot
Hi,
How can I calculate and mark each group centroid in a linear discriminant
analysis plot (using ggplot2)?
Script:
## originate from
http://r.789695.n4.nabble.com/LDA-and-confidence-ellipse-td4671308.html
require(MASS)
require(ggplot2)
iris.lda<-lda(Species ~ Sepal.Length + Sepal.Width + Petal.Length +
Petal.Width, data = iris)
LD1<-predict(iris.lda)$x[,1]
2000 Mar 08
3
Reading data for discriminant analysis
Dear R users,
I want to do discriminant analysis on my data. I have
successfully followed the discriminant analysis in V & R on
the iris data:
> ir <- rbind (iris3[,,1],iris3[,,2],iris3[,,3])
> ir.species <- c(rep("s",50),rep("c",50),rep("v",50))
> a <- lda(log(ir),ir.species)
> a$svd^2/sum(a$svd^2)
[1] 0.996498601 0.003501399
> a.x <-
2009 Nov 18
0
Y axis of 1-D Linear Discriminant Histograms
Hi all.
I would like to understand what are the units defined on the y-axis
when you plot the one-dimensional predictions (histograms) from lda()
(MASS) discriminant function objects?
While the helpfile suggests that a histogram is returned by default,
the presumably proportion-like values for each group seem to add up to
more than 1, and I'm not sure how to interpret the code from
ldahist(),
2005 Sep 05
2
Fisher's method in discriminant analysis
Hi,
I'm using mda library to solve a discriminant
analysis. I get results, but the thing is that I want
to use Fisher's method to obtain the classification
functions and I'm lost in what I should do: libraries
to use, ... Can anybody give me a clue??
Thanks.
Carlos Niharra L??pez
2010 Nov 16
3
discriminant function analysis
My objective is to look at differences in two species of fish from morphometric measurements. My morphometric measurements are head length, eye diameter, snout length, and measurements from tail to each fin. I want to use discrimanant function analyis to determine if there are differences between the two species.
I am familiar with R but new to discrimannt function analysis. I want to learn
2007 Jun 18
0
discriminant analysis with lda(MASS)
I use Widows, R version 2.4.1
I have 4 questions on lda (MASS) (code is pasted below):
1st. How can I obtain the statistics and p-value associated with
discriminant analysis? Am I supposed to calculate that manually by squaring
the svd value and looking the p value up in a table? I am writing the
following code:
training.mx<-read.table('C:\\Documents and Settings\\silvia\\My
2005 Apr 07
2
axis colors in pairs plot
The following command produces red axis line in a pairs
plot:
pairs(iris[1:4], main = "Anderson's Iris Data -- 3 species",
pch = "+", col = c("red", "green3", "blue")[unclass(iris$Species)])
Trying to fool pairs in the following way produces the
same plot as above:
pairs(iris[1:4], main = "Anderson's Iris Data -- 3
2011 Jul 28
2
not working yet: Re: lattice overlay
Hi Dieter and R community:
I tried both of these three versions with ylim as suggested, none work: I
am getting only single (pch = 16) not overlayed (pch =3) everytime.
*vs 1*
require(lattice)
xyplot(Sepal.Length ~ Sepal.Width | Species , data= iris,
panel= function(x, y, subscripts) {
panel.xyplot(x, y, pch=16, col = "green4", ylim = c(0, 10))
panel.lmline(x, y, lty=4, col =
2007 Oct 02
1
splom pairs and groups argument
Hello,
I'm trying to pull off a certain graph using splom, and can't quite get my panel functions right.
Basically, the equivalent using pairs would be something like this (using iris data set as an example):
panel.corval <- function(x, y, digits=2, prefix="", cex.cor,col,pch)
{
usr <- par("usr"); on.exit(par(usr))
par(usr = c(0, 1, 0, 1))
2012 Oct 21
1
Linear discriminant function analysis based median as group centroid and nonparametric scale estimators???
Dear All,
I am using a specific approach for my master thesis. In essence, a
supervised reclassification is used as an intermediate step to find chemical
parameters which are able to reclassify defined groups. These variables will
be used in a next step where location and scale estimators of the groups are
important. Traditionally linear discriminant analysis is used for
reclassification which
2009 Apr 09
0
Discriminant Analysis Ellipse
Hi listers,
I am working on a program in order to create an ellipse as a limit of my
observations there are well classified.
I have two independent variables for an quadratic discriminant function
between 2 groups where my mean is zero and my covariance matrix is
proportional.
Q=y'Ay+c
My program follows below with unreal data... My ellipse it's not surrounding
the correct number of
2001 Sep 25
2
pairs() Legend
Hi,
Is it possible to create a legend in a pairs() plot?
For example, suppose I have the following R codes:
data(iris)
pairs(iris[1:4], main = "Anderson's Iris Data -- 3 species",
pch = 21, bg = c("red", "green3", "blue")[codes(iris$Species)])
How can I created a legend that shows which colour represents to which
Iris species?
Thanks,
2009 Feb 25
2
Linear Discriminant Analysis
Kindly let me know the process to carry out a Linear discriminant
analysis...thanks in advance
Arup
--
View this message in context: http://www.nabble.com/Linear-Discriminant-Analysis-tp22199424p22199424.html
Sent from the R help mailing list archive at Nabble.com.
2011 Feb 18
1
segfault during example(svm)
If do:
> library("e1071")
> example(svm)
I get:
svm> data(iris)
svm> attach(iris)
svm> ## classification mode
svm> # default with factor response:
svm> model <- svm(Species ~ ., data = iris)
svm> # alternatively the traditional interface:
svm> x <- subset(iris, select = -Species)
svm> y <- Species
svm> model <- svm(x, y)
svm>
2005 Oct 04
1
pdf plotting of splom
Hi,
The following code produces a plot on X11:
splom(~iris[1:4], groups = Species, data = iris,
panel = panel.superpose,
key = list(title = "Three Varieties of Iris",
columns = 3,
points = list(pch = super.sym$pch[1:3],
col = super.sym$col[1:3]),
text = list(c("Setosa", "Versicolor", "Virginica"))))
However,
2005 Apr 28
0
Linear Discriminant Analysis Biplots
Dear R
I'm trying to plot the lda means onto a 2 D plot of discriminant scores.
Preferably I'd like these to be in a larger font compared to the
discriminant scores.
I tried
skull.mean.pred <- predict(skulls.lda, as.data.frame(skulls.lda$means),
dimen=2)
from which I got
skull.mean.pred
$class
[1] 1 2 3 4 5
Levels: 1 2 3 4 5
$posterior
1 2 3 4
2009 Jan 31
1
display p-values and significance levels
Hi there,
I got a piece of code for the Iris data which allows to display correlation
coefficients for each Iris species in the lower panel (color coded). I would
now like to add e.g. a "*" to show the significance of each correlation next
to the correlation coefficient.
Furthermore I would like to make a t.test between the species "setosa" and
"versicolor" for
2008 Aug 26
1
more dot plots on 1 page
Hi,
I would like to have six dot plots on one page. I make the plots in a
'for loop' because it is six times the same graph but for different
subjects (species).
I tried it with "par(mfrow=c(3,2), oma=c(3,3,2,0), mar=c(2,2,2,2))"; but
this does not work for dot plots apparently.
Then I tried with print(). But then I had to give the dot plots names.
This also does not work.
2010 Dec 14
4
Discriminant Correspondence Analysis
Hello everyone,
I am totally new to the R program. I have had a look at some pdf documents
that I downloaded and that explain how to do many things in R; however, I
still cannot figure out how to do what I want to do, which is to perform
Discriminant Correspondence Analysis on a rectangular matrix of data that I
have in an Excel file. I know R users frown upon Excel and recommend
converting Excel
2009 May 24
1
Animal Morphology: Deriving Classification Equation with Linear Discriminat Analysis (lda)
Fellow R Users:
I'm not extremely familiar with lda or R programming, but a recent editorial
review of a manuscript submission has prompted a crash cousre. I am on this
forum hoping I could solicit some much needed advice for deriving a
classification equation.
I have used three basic measurements in lda to predict two groups: male and
female. I have a working model, low Wilk's lambda,