Displaying 20 results from an estimated 3000 matches similar to: "lda"
2005 Aug 15
1
error in predict glm (new levels cause problems)
Dear R-helpers,
I try to perform glm's with negative binomial distributed data.
So I use the MASS library and the commands:
model_1 = glm.nb(response ~ y1 + y2 + ...+ yi, data = data.frame)
and
predict(model_1, newdata = data.frame)
So far, I think everything should be ok.
But when I want to perform a glm with a subset of the data,
I run into an error message as soon as I want to predict
2004 Jul 03
1
graphic representation of a qda object
Hi,
I'm a R newbie and I have a supervised 2-class classification problem.
To find out the best representation of my data (dim = 45). I want to perform LDA und QDA on the diffrent data representations to find out, which is best to discriminate the 2 sets. For LDA there exists a method plot.lda shows (in the 2 class case) a histogramm of the data, projected onto the linear discriminants (pleas
2005 Aug 16
1
predict nbinomial glm
Dear R-helpers,
let us assume, that I have the following dataset:
a <- rnbinom(200, 1, 0.5)
b <- (1:200)
c <- (30:229)
d <- rep(c("q", "r", "s", "t"), rep(50,4))
data_frame <- data.frame(a,b,c,d)
In a first step I run a glm.nb (full code is given at the end of this mail) and
want to predict my response variable a.
In a second step, I would
2005 Feb 23
3
bias of a boot statistic
Question:
How can I get access to the bias value of a boot statistic?
Details:
Boot function:
boot(data, statistic, R, sim="ordinary", stype="i",
strata=rep(1,n), L=NULL, m=0, weights=NULL,
ran.gen=function(d, p) d, mle=NULL, ...)
When I create an object, containing the bootstrap statistic (object <- boot
(....))I can call it and will get an output
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 Sep 29
1
Fisher's discriminant functions
Hi everyone,
I'm trying to solve a problem about how to get the
Fisher's discriminant functions of a "lda" (linear
discriminant analysis) object, I mean, the object
obtained from doing "lda(formula, data)" function of
the package MASS in R-project. This object gives me
the canonical linear functions (n-1 coefficients
matrix of n groups at least), and only with this
2009 Dec 10
1
Samba PDC LDAP and LDAP Aliases
Hello all
I've got a problem with unresolved (at least I guess that) LDAP Aliases
and Samba. That's my LDAP Setup:
ou=alvhaus,ou=ch { base }
ou=People,ou=alvhaus,ou=ch { posix and samba accounts }
ou=Group,ou=alvhaus,ou=ch { posix and samba groups }
ou=Samba,ou=alvhaus,ou=ch { samba base dn }
ou=Idmap,ou=Samba,ou=alvhaus,ou=ch
ou=Machines,ou=Samba,ou=alvhaus,ou=ch
2012 Feb 29
1
equivalent from gladder and ladder from stata
Dear community,
Apologies, I'm still pretty newbie. Anyway, I am performing linar regression
analysis. As a common cause of non-normally distributed residuals is
non-normally predictor variables, i'm interested in achieving the best
transformation of the predictors.
I've seen some commands at R, but I would like to know if it exists a
command equivalent to gladder (graphic display)
2005 Jul 05
4
Discriminant Function Analysis
Dear All
This is more of a statistics question than a question about help for R,
so forgive me.
I am using lda from the MASS package to perform linear discriminant
function analysis. I have 14 cases belonging to two groups and have
measured each of 37 variables. I want to find those variables that best
discriminate between the two groups, and I want to visualise that and
create a
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
2011 Sep 18
2
R-Help
Hi, my name is Gastón. I just read a question, made by Walter Durka, about a
nonparametric discriminant analysis. It wasn´t any answer, and I was
wondering if at this moment there is one. I have the same problem as W.
Durka. I´m trying to classify and to cross-validate samples of three
tunicates species based on morphometric data and to identify the variables
that best discriminate between
2003 Apr 02
1
lda of MASS library
Hi,
it seems that the lda function in MASS library doesn''t give out the constant for the linear discriminant function under the situation that we don''t use standardized variable, anyone knows how to obtain the constant in order to construct the linear discriminant function?
I understand that if the priors are set to be 1/2, the threshold of the discriminant score used to
2005 Jun 15
1
2 LDA
Hi,
I am using Partek for LDA analysis. For a binary
response variable, it generates 2 discriminant
functions, one for each of the 2 levels of the
response variable. And I can simply calculate 2
discriminant scores (say d1 and d2) for each sampples
using the 2 discriminant functions, then I can use the
following formula to compute the posterior probability
for the sample:
2004 Jul 22
1
Disriminant analysis with lda (MASS)
Hello,
Does the "lda" function (package MASS) perform or can it perform classic
two-group Fisher discriminant analysis?
R-version: 1.9.1, MASS package (latest available)
Thank you,
Borut Rajer
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)))
2004 Jun 10
2
nls and R scoping rules
I apologize for posting this in essence the second time (no light at the
end of the tunnel yet..):
is there a way to enforce that "nls" takes both, the data *and* the
model definition from the parent environment? the following fragment
shows the problem.
#======== cut here==========
wrapper <- function (choose=0)
{
x <- seq(0,2*pi,len=100)
y <- sin(1.5*x);
y <-
2005 Aug 05
1
lda discriminant functions
Hi list,
I'm looking about lda function.
I'd like to know how calcolate the value of the discriminant functions for the
original datas.
I see that in the result object "lda" there is $scaling a matrix which
transforms observations to discriminant functions, normalized so that within
groups covariance matrix is spherical.
I'd like to have the value of the discriminant
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,
2005 Jul 08
2
extract prop. of. var in pca
Dear R-helpers,
Using the package Lattice, I performed a PCA.
For example
pca.summary <- summary(pc.cr <- princomp(USArrests, cor = TRUE))
The Output of "pca.summary" looks as follows:
Importance of components:
Comp.1 Comp.2 Comp.3 Comp.4
Standard deviation 1.5748783 0.9948694 0.5971291 0.41644938
Proportion of Variance 0.6200604
2010 Jul 04
2
help with predict.lda
HI, Dear community,
I am using the linear discriminant analysis to build model and make new
predictions:
> dim(train) #training data
[1] 1272 22
> dim(valid) # validation data
[1] 140 22
lda.fit <- lda(out ~ ., data=train, na.action="na.omit", CV=TRUE) # model
fitting of linear discriminant analysis on training data
> predict(lda.fit, valid) # make prediction on