Displaying 20 results from an estimated 1000 matches similar to: "discriminant analysis with lda(MASS)"
2004 May 24
1
discriminant analysis
Hi,
I have done different discriminant function analysis of multivariat data. With the CV=True option I was not able to perform the predict() call. What do I have to do? Or is there no possibility at all? You also need the predicted values to produce a plot of the analysis, as far as I know.
Here my code:
pcor.lda2<-lda(pcor~habarea+hcom+isol+flowcov+herbh+inclin+windprot+shrubcov+baregr,
2005 Jun 16
1
how to use plot.lda included in MASS package?
Hi there,
I am a master student in Denmark, and apply R to analyze the drug data.
I use the function 'lda' to obtain a linear discriminant object, and
then wish to use 'plot.lda' to do the plot on this object like below.
drug.lda <- lda(Inhibition ~ NET_CHARGE + PKA_1 + MW + MLOGP,
data = drug.class, method = "moment")
plot.lda(drug.lda,
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
$posterior
1 2 3 4
2009 Nov 18
0
Y axis of 1-D Linear Discriminant Histograms
Hi all.
I would like to understand what are the units defined on the y-axis
when you plot the one-dimensional predictions (histograms) from lda()
(MASS) discriminant function objects?
While the helpfile suggests that a histogram is returned by default,
the presumably proportion-like values for each group seem to add up to
more than 1, and I'm not sure how to interpret the code from
ldahist(),
2011 Jun 09
0
(no subject)
> #
>> # Generate the figures (on screen)
>> #
>> # Image generation - function definition
>> pic_onscr<-function(matrix, title, cex_val=1)
> + {x11() + par(mgp=c(5,2,0), # axis margins + # (title,
> labels, line) + mar=c(7,4,4,2), # plot margins (b,l,t,r) +
> las=1) # horizontal labels + plot(matrix, # data to plot +
>
2000 Mar 08
3
Reading data for discriminant analysis
Dear R users,
I want to do discriminant analysis on my data. I have
successfully followed the discriminant analysis in V & R on
the iris data:
> ir <- rbind (iris3[,,1],iris3[,,2],iris3[,,3])
> ir.species <- c(rep("s",50),rep("c",50),rep("v",50))
> a <- lda(log(ir),ir.species)
> a$svd^2/sum(a$svd^2)
[1] 0.996498601 0.003501399
> a.x <-
2011 Jun 09
1
what is the mistake?? the coding still not function. no result display
# lda.r
> #
> # Author: Amsha Nahid, Jairus Bowne, Gerard Murray
> # Purpose: Perform Linear Discriminant Analysis (LDA)
> #
> # Input: Data matrix as specified in Data-matrix-format.pdf
> # Output: LDA plot
> #
> # Notes: Missing values (if any) are replaced by the half of the lowest
> # value in the entire data matrix.
>
2011 Jun 21
1
(no subject)
hello,
i already include the error in blue color word.
i hope it can help you to understand my question.
if not burden you, please give me a guide how to correct the error or maybe you
can correct the coding cause error.
thank you.
> # lda.r
> #
> # Author: Amsha Nahid, Jairus Bowne, Gerard Murray
> # Purpose: Perform Linear Discriminant Analysis (LDA)
> #
> #
2007 Oct 16
1
error in sample ()
I am trying to get a random matrix based on an original matrix called
disperser.mx, with dimensions 30x73
When I write the following code:
>scramble = sample (disperser.mx)
>newmat = matrix(scramble, nrow=30)
I get the following warning message and a very weird matrix with 30 rows but
only 3 columns shown below:
Warning message:
data length [73] is not a sub-multiple or multiple of the
2004 Nov 02
2
lda
Hi !!
I am trying to analyze some of my data using linear discriminant analysis.
I worked out the following example code in Venables and Ripley
It does not seem to be happy with it.
============================
library(MASS)
library(stats)
data(iris3)
ir<-rbind(iris3[,,1],iris3[,,2],iris3[,,3])
ir.species<-factor(c(rep("s",50),rep("c",50),rep("v",50)))
2006 Feb 20
1
linear discriminant analysis in MASS
Hello R people
I now know how to run my discriminant analysis with the lda function in
MASS:
lda.alain=lda(Groupes ~ Ht.D0 + Lc.Dc + Ram + IDF, gr, CV = FALSE)
and it works fine.
But I am missing a test and cannot find any help on how to get it, if it
exist.
The "S" equivalent:
discrim(structure(.Data = Groupes ~ Ht.D0 + Lc.Dc + Ram + IDF, class =
"formula"), data = gr,
2012 Aug 01
1
Different results between lda(mass) and spss discriminant analysis
Hi all,
I obtained a strage result with LDA (MASS) function in R with NIR data.
I tried both CV (leave one out cross validation) and splitting my data in
odd (training) and even (prediction) sets.
In all the cases the minimum error was near to 0.
Due to the strange result, I tried with SPSS IBM software and it give me
around 11% of minimum error with and without leave one out cross validation.
2007 Sep 20
0
error in manova
I work with Windows, R 2.4.1. I'm a beginner with R!
After doing a Discriminant Function Analysis, I am trying to run manova to
get a measure of significance of my lda results. I want to predict groups 1
through 4 using 78 variables (bad group/var ratio, I know, but I'm just
exploring the possibilities right now). I've tried with a test matrix and I
get my results fine, so I think
2007 Aug 22
1
plotting lda results
Hi all,
I am trying to plot the results of a discriminant analysis done with
lda(MASS) but my groups appear in two different plots (in the same graphics
device) and I want to combine them in one plot. My code looks like:
BirdTrain.lda <- lda(Bdisperser~., data=BirdTrain.mx)
predict(BirdTrain.lda)
plot(BirdTrain.lda)
I have two types of Bdisperser, so I only get one linear discriminant
2007 Apr 02
0
Plots from lda and predict.lda
Dear all
When plotting the results of lda and predict.lda, I expect the axis
dimensions to remain essentially the same - predict.lda projects new
observations onto linear discriminants. However, I am getting different
ranges of values along the x-axis when producing plots following each:
plot(lda) yields values in the range approximately -3 to +4, while
plot(predict.lda) yields values for the
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 May 25
1
Problem with rpart
I work on Windows, R version 2.4.1. I'm very new with R!
I am trying to build a classification tree using rpart but, although the
matrix has 108 variables, the program builds a tree with only one split
using one variable! I know it is probable that only one variable is
informative, but I think it's unlikely. I was wondering if someone can help
me identify if I'm doing something
2007 Oct 03
1
help with stepclass (klaR)
I use Windows, R version 2.5.1
When I try to run stepclass (klaR) I get an error message/warning saying:
1: error(s) in modeling/prediction step in: cv.rate(vars = c(model, tryvar),
data = data, grouping = grouping, ...
Actually, I look 16 warnings of this type. Can anyone tell me what this
means?
Also, it returns only 2 out of the 79 variables as important, however these
variables
2017 Nov 21
2
mystery "158"
This is a simple problem, but a mystery to me.
I'm trying to grab $Family "Scelionidae" from one dataframe and put it into
another dataframe occupied with NA in $Family. The result is a "158" ends
up there instead of Scelionidae.
Simply put fam$Family[1] <- least$Family[1]
If I have made a mistake here, can somebody point it out. I've included
the simple
2017 Nov 21
0
mystery "158"
Your data frame fam contains factors. Turn it into character strings using
fam$Family = as.character(fam$Family)
and try again. It may be helpful if you read up on R's factors, see ?factor.
HTH,
Peter
On Tue, Nov 21, 2017 at 2:14 PM, Glen Forister <gforister at gmail.com> wrote:
> This is a simple problem, but a mystery to me.
> I'm trying to grab $Family