Displaying 20 results from an estimated 1000 matches similar to: "Fisher's discriminant functions"
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
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
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)$x[,1]
2009 Oct 14
1
plot discriminant analysis
I'm confused on how is the right way to plot a discriminant analysis made by
lda function (MASS package).
(I had attached my data fro reproduction). When I plot a lda object :
X <- read.table("data", header=T)
lda_analysis <- lda(formula(X), data=X)
plot(lda_analysis)
#the above plot is completely different to:
plot(predict(lda_analysis)$x,
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 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
$posterior
1 2 3 4
2004 May 24
1
discriminant analysis
Hi,
I have done different discriminant function analysis of multivariat data. With the CV=True option I was not able to perform the predict() call. What do I have to do? Or is there no possibility at all? You also need the predicted values to produce a plot of the analysis, as far as I know.
Here my code:
pcor.lda2<-lda(pcor~habarea+hcom+isol+flowcov+herbh+inclin+windprot+shrubcov+baregr,
2005 Aug 05
2
Discriminant analysis
Hi,
I'm a newbie in R and don't much aobut all the
modules and their capabilities, but I'm interested in
solving a problem about a discriminant analysis done
with SPSS tool. The thing is that I would like to make
a discrimant analysis similar to the one done with
SPSS, but I can't find the way to solve it.
I've been playing with R and I can handle more or
less my data,
2013 Feb 20
1
Plotting Discriminants from qda
Dear R Help Members,
I am aware how to plot the LD1 vs LD2 from a lda in R, using the code:
plot(baseline.systat.hat$x, col=baseline.systat.hat$class,pch=as.numeric(baseline.systat.hat$class))
However, I need to use the quadratic discriminant function, qda due to data properties. Is there a way to obtain the same sort of plot for from a qda object (and the output of predict qda). I have not
2012 Jun 11
1
saving sublist lda object with save.image()
Greetings R experts,
I'm having some difficulty recovering lda objects that I've saved within sublists using the save.image() function. I am running a script that exports a variety of different information as a list, included within that list is an lda object. I then take that list and create a list of that with all the different replications I've run. Unfortunately I've been
2012 Nov 08
0
mirt vs. eRm vs. ltm vs. winsteps
Dear R-List,
I tried to fit a partial credit model using the "pcmdat" from eRm-package comparing the results of mirt, eRm, ltm and winsteps.
The results where quite different, though. I cannot figure out what went wrong and I do not know which result I can rely on.
This is what I did in R
library(mirt)
#load(file="u3.RData")
2010 Jun 06
1
I need help in analyzing
I'm sory for my weak english. I need to analyze this subject :
x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 y
0 0 1 0 0 1 0 0 1 0 czarne
1 1 0 0 0 0 1 0 0 0 rude
0 0 1 0 0 1 1 0 0 0 braz
0 0 1 0 1 0 1 0 0 0 blond
1 0 0 0 0 1 0 0 0 1 rude
1 1 0 0 0 0 0 0 0 1 blond
0 0 1 1 0 0 0 0 1 0 czarne
1 0 0 1 0 0 1 0 0 0 blond
0 0 1 0 0 1 1 0 0 0 blond
1 0 0 0 0 1 1 0 0 0 czarne
0 0 1 0 0 1 0 0 0 1 czarne
1 0 1 0 0 0
2007 Jun 18
0
help with panel.lda
I work with Windows, R version 2.4.1
I am trying to plot the results of a discriminant analysis done using the
lda function in the MASS library. The discriminant. analysis goes like this:
data.tb<-read.table('C:\\Documents and
Settings\\silvia\\Desktop\\dicrim_test.txt', header=T) ## the actual made-up
test matrix is pasted below
train<-sample (1:36, 15)
table
2005 Jul 25
0
lda: scaling to 'disctiminant function'
Friends
Briefly...
In the documentation for lda in MASS it describes the value 'scaling' as
'a matrix which transforms observations into discriminint functions...'.
How?
Verbosely...
I have a matrix of data. 9 independent variables and describing
3-classes. About 100 observations in total. A 10x100 matrix of data.
I am trying to generate two discriminant functions and i
2012 Aug 14
0
[LLVMdev] Load serialisation during selection DAG building
Further to my earlier question, I'm perhaps a bit confused about memory serialisation. The following example, compiled using clang for the MSP430:
target datalayout = "e-p:16:16:16-i8:8:8-i16:16:16-i32:16:32-n8:16"
target triple = "msp430-??-??"
@y = common global i16 0, align 2
@x = common global i16 0, align 2
define void @f() nounwind {
entry:
%0 = load i16* @y,
2011 Jul 27
0
[LLVMdev] Avoiding load narrowing in DAGCombiner
On Wed, Jul 27, 2011 at 3:50 PM, Matt Johnson
<johnso87 at crhc.illinois.edu> wrote:
> Hi Eli,
>
> On 07/27/2011 04:59 PM, Eli Friedman wrote:
>>
>> On Wed, Jul 27, 2011 at 2:28 PM, Matt Johnson
>> <johnso87 at crhc.illinois.edu> wrote:
>>>
>>> Hi All,
>>> I'm writing a backend for a target which only supports 4-byte,
2012 Aug 14
2
[LLVMdev] Load serialisation during selection DAG building
I looked into those patches but I don't think they will help in my situation because my problems occur during instruction selection rather than scheduling.
A simple and concrete example is a pattern like:
[(set GR:$dst (add GR:$src (nvload addr:$mem)))]
where nvload matches a load provided that isVolatile() is false.
If the selection DAG looks like:
| |
LD1 LD2
^
2011 Jul 27
2
[LLVMdev] Avoiding load narrowing in DAGCombiner
Hi Eli,
On 07/27/2011 04:59 PM, Eli Friedman wrote:
> On Wed, Jul 27, 2011 at 2:28 PM, Matt Johnson
> <johnso87 at crhc.illinois.edu> wrote:
>> Hi All,
>> I'm writing a backend for a target which only supports 4-byte,
>> 4-byte-aligned loads and stores. I custom-lower all {*EXT}LOAD and
>> STORE nodes in TargetISelLowering.cpp to take advantage of
2015 Mar 03
3
[LLVMdev] ReduceLoadWidth, DAGCombiner and non 8bit loads/extloads question.
I'm curious about this code in ReduceLoadWidth (and in DAGCombiner in
general):
if (LegalOperations && !TLI.isLoadExtLegal(ExtType, ExtVT))
return SDValue
<http://llvm.org/docs/doxygen/html/classllvm_1_1SDValue.html>();
LegalOperations is false for the first pre-legalize pass and true for the
post-legalize pass. The first pass is target-independent yes? So that makes
sense.
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(),