Displaying 20 results from an estimated 9000 matches similar to: "About classification methods."
2011 Feb 11
1
R for mac, default load package.
Dear R users,
I'm looking for solution about how can I add a package to default load package list.
Because, some packages, every time I use the package for analysis. I don't want type "load(package)" every time.
On the R instruction, I should change .Rprofile file, but I couldn't find R for Mac.
How can I add default load package?
Jaeik Cho
2005 Jul 01
1
p-values for classification
Dear All,
I'm classifying some data with various methods (binary classification). I'm interpreting the results via a confusion matrix from which I calculate the sensitifity and the fdr. The classifiers are trained on 575 data points and my test set has 50 data points.
I'd like to calculate p-values for obtaining <=fdr and >=sensitifity for each classifier. I was thinking about
2004 Nov 04
4
highly biased PCA data?
Hello, supposing that I have two or three clear categories for my data,
lets say pet preferece across fish, cat, dog. Lets say most people rate
their preference as being mostly one of the categories.
I want to do pca on the data to see three 'groups' of people, one group
for fish, one for cat and one for dog. I would like to see the odd person
who likes both or all three in the
2010 Jul 11
1
Is there a "Mixed effect model" for regression/classification trees?
Hello all,
This is more a statistical question then an R question, but I am sure it
will have an R interpretation to it.
If I wish to predict an outcome based on some potential features, I could
(in some cases) use either regression or regression-tree.
However, if my observations are divided to groups (for example by
"subject"), I might then want to model that using a random effect for
2012 Nov 19
2
Classification methods - which one?
Dear all,
i searched for some classification methods and I have no glue if i took the right once.
My problem: I have a matrix with 17000 rows and 33 colums (genes and patients). The patients are grouped into 3 diseases.
No I want to classify the patients and for sure i want to know which rows are more helpful for the classification than others.
I tried SVM and random forest. Do you think this
2009 Nov 02
1
kernel density estimation and classification
Hi,
I am interested to use Kernel Density Estimation on bivariate data for multi-class classification.
So far, I have managed to use the 'ks' package to plot the contours of the kernel density estimates based on 8-class training dataset with only 2 variables.
However, I do not know how to make use of the Kernel Density Analysis results as input into a classifier (e.g. Bayesian
2010 Jan 22
2
Computing Confidence Intervals for AUC in ROCR Package
Dear R-philes,
I am plotting ROC curves for several cross-validation runs of a
classifier (using the function below). In addition to the average
AUC, I am interested in obtaining a confidence interval for the
average AUC. Is there a straightforward way to do this via the ROCR
package?
plot_roc_curve <- function(roc.dat, plt.title) {
#print(str(vowel.ROC))
pred <-
2012 Feb 09
1
Tr: Re: how to pass weka classifier options with a meta classifier in RWeka?
Le jeudi 09 f?vrier 2012 ? 15:31 +0200, Kari Ruohonen a ?crit :
> Hi,
> I am trying to replicate a training of AttributeSelectedClassifier with
> CFsSubsetEval, BestFirst and NaiveBayes that I have initially done with
> Weka. Now, I am trying to use RWeka in R.
>
> I have a problem of passing arguments to the CfsSubsetEval, BestFirst
> and NaiveBayes. I have first created an
2010 Apr 23
3
Practical work with logistic regression
Dear all,
I have a couple of short noob questions for whoever can take them. I'm
from a very non-stats background so sorry for offending anybody with
stupid questions ! :-)
I have been using logistic regression care of glm to analyse a binary
dependent variable against a couple of independent variables. All has
gone well so far. In my work I have to compare the accuracy of
analysis to a C4.5
2011 Oct 19
0
R classification
hello, i am so glad to write you.
i am dealing now with writing my M.Sc in Applied Statistics thesis, titled " Data Mining Classifiers and Predictive Models Validation and Evaluation".
I am planning to compare several DM classifiers like "NN, kNN, SVM, Dtree, and Naïve Bayes" according to their Predicting accuracy, interpretability, scalability, and time consuming etc.
I have
2004 Jan 07
1
Questions on RandomForest
Hi, erveryone,
I show much thanks to Andy and Matthew on former questions. I now sample
only a small segment of a image can segment the image into several classes
by RandomForest successfully. Now I have some confusion on it:
1. What is the internal component classifier in RandomForest? Are they the
CART implemented in the rpart package?
2. I use training samples to predict new samples. But
2011 Oct 26
1
Random Forest Classification
Hi All,
I wrant to do Random Forest classification. I installed R, randomForest
classifier package for R
but dont know how to use it.
Is there any Open Source Remote sensing application which do RF
classification on satellite images?
Anyone r has random forest classification example?
Any language or package example no problem.
Does anyone did it in R?
if yes how?
I google RF Classification
2010 Nov 09
1
randomForest parameters for image classification
I am implementing an image classification algorithm using the
randomForest package. The training data consists of 31000+ training
cases over 26 variables, plus one factor predictor variable (the
training class). The main issue I am encountering is very low overall
classification accuracy (a lot of confusion between classes). However, I
know from other classifications (including a regular decision
2001 May 16
7
Naive Bayes Classifier
Dear r-users,
I am looking for an implementation of the Naive Bayes classifier for a
multi-class classification problem. I can not even find the Naive Bayes
classifier for two classes, though I can not believe it is not
available. Can anyone help me?
Uschi
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r-help mailing list -- Read
2012 Nov 15
1
Can't see what i did wrong..
with
pred.pca<-predict(splits[[i]]$pca,trainingData at samples)[,1:nPCs]
dframe<-as.data.frame(cbind(pred.pca,class=isExplosive(trainingData,2)));
results[[i]]$classifier<-ksvm(class~.,data=dframe,scaled=T,kernel="polydot",type="C-svc",
C=C,kpar=list(degree=degree,scale=scale,offset=offset),prob.model=T)
and a degree of 5 i get an error of 0 reported by the ksvm
1999 Sep 22
2
SAMBA digest 2240
>
Hi,
Check if the shared directory has the write permission for all. i.e. chmod 777 for
the particular directory
> Date: Sun, 19 Sep 1999 21:06:36 -0700
> From: Kenny Cho <Kenny.Cho@Corp.Sun.COM>
> To: samba@samba.org
> Subject: Problem copying files to samba mount.
> Message-ID: <37E5B2CC.9ADC9F8A@ha1pal.corp.sun.com>
> MIME-Version: 1.0
>
2004 Dec 13
2
classification for huge datasets: SVM yields memory troubles
Hi
I have a matrix with 30 observations and roughly 30000 variables, each
obs belongs to one of two groups. With svm and slda I get into memory
troubles ('cannot allocate vector of size' roughly 2G). PCA LDA runs
fine. Are there any way to use the memory issue withe SVM's? Or can you
recommend any other classification method for such huge datasets?
P.S. I run suse 9.1 on a 2G RAM
2002 Apr 02
2
random forests for R
Hi all,
There is now a package available on CRAN that provides an R interface to Leo
Breiman's random forest classifier.
Basically, random forest does the following:
1. Select ntree, the number of trees to grow, and mtry, a number no larger
than number of variables.
2. For i = 1 to ntree:
3. Draw a bootstrap sample from the data. Call those not in the bootstrap
sample the
2002 Apr 02
2
random forests for R
Hi all,
There is now a package available on CRAN that provides an R interface to Leo
Breiman's random forest classifier.
Basically, random forest does the following:
1. Select ntree, the number of trees to grow, and mtry, a number no larger
than number of variables.
2. For i = 1 to ntree:
3. Draw a bootstrap sample from the data. Call those not in the bootstrap
sample the
2010 Aug 30
2
Regarding naive baysian classifier in R
Hi,
I have a small doubt regarding naive Bayes. I am able to classify the
data's properly but i am just stuck up with how to get the probability
values for naive bayes. In the case of SVM we have "attr" function that
helps in displaying the probability values. Is there any function similar to
"attr" in naive Bayes that can be used for displaying the attribute values.
my