Displaying 20 results from an estimated 2000 matches similar to: "nnet classification using unbalanced classes"
2004 May 04
1
nnet function
Hi I got two questions about the nnet function in R. I would be thankful to
have an answer.
1) Does the function intrinsically normalize the X and Y matrices before
the training, or normalization should be
done by the user.
2) I need to understand the $wts matrix. I do imagine that it is a single
column transformation of the two
matrices of weighs (input to hidden Ninputs+1 x Nodes) and
2004 Jun 15
1
building R libraries (windows) - R CMD check problems
Hi everyone,
I am trying to build a R library called nnNorm but I have some troubles
checking and installing it.
Here is the setup:
If I don't use a inst\doc directory(with the vignettes files) in my source,
the install step is working fine:
C:\test>RCMD INSTALL nnNorm
---------- Making package nnNorm ------------
adding build stamp to DESCRIPTION
installing R files
installing
2005 Aug 26
1
passing arguments from nnet to optim
Hi everyone,
According to R reference manual, the nnet function uses the BFGS method
of optim to optimize the neural network parameters.
I would like, when calling the function nnet to tell the optim function
not to produce the tracing information on the progress of the
optimization, or at least to reduce the frequency of the reports.
I tried the following:
a) nnet default
> x<-rnorm(20)
2010 Nov 26
1
Issues with nnet.default for regression/classification
Hi,
I'm currently trying desperately to get the nnet function for training a
neural network (with one hidden layer) to perform a regression task.
So I run it like the following:
trainednet <- nnet(x=traindata, y=trainresponse, size = 30, linout = TRUE, maxit=1000)
(where x is a matrix and y a numerical vector consisting of the target
values for one variable)
To see whether the network
2004 Mar 13
4
nnet classification accuracy vs. other models
I was wandering if anybody ever tried to compare the classification
accuracy of nnet to other (rpart, tree, bagging) models. From what I
know, there is no reason to expect a significant difference in
classification accuracy between these models, yet in my particular case
I get about 10% error rate for tree, rpart and bagging model and 80%
error rate for nnet, applied to the same data.
Thanks.
2004 Mar 30
1
classification with nnet: handling unequal class sizes
I hope this question is adequate for this list
I use the nnet code from V&R p. 348: The very nice and general function
CVnn2() to choose the number of hidden units and the amount of weight
decay by an inner cross-validation- with a slight modification to use it
for classification (see below).
My data has 2 classes with unequal size: 45 observations for classI and
116 obs. for classII
With
2011 Sep 16
1
parsing error when using R CMD check
Hi all,
I am trying to run R CMD check on a package which passes R CMD INSTALL.
The check stops because of a parsing problem in the example of a given function at this line:
return(res[res$ID %in% list$targetGeneSets,])
The code is ok, since it runs if I paste it in R.
Is this a known parsing issue in R CMD check?
Thanks,
Adi
> sessionInfo()
R version 2.13.0 (2011-04-13)
Platform:
2006 Apr 10
5
p values for a GEE model
Hi all,
I have a dataset in which the output Y is observed on two groups of
patients (treatment factor T with 2 levels).
Every subject in each group is observed three times (not time points but
just technical replication).
I am interested in estimating the treatment effect and take into account
the fact that I have repeated measurements for every subject.
If I do this with repeated measures
2006 Mar 23
0
front- end problem while using nnet and tune.nnet
Dear R people,
I am using tune.nnet from e1071 package to tune the parameters for nnet.
I am using the following syntax:
tuneclass <-c(rep(1,46),rep(2,15))
tunennet
<-tune.nnet(x=traindata,y=tuneclass,size=c(50,75,100),decay=c(0,0.005,0.010),MaxNWts
= 20000)
Here traindata is the training data that I want to tune for nnet which
is a matrix with 61 rows(samples) and 200
2000 Aug 02
0
? predict.nnet
Hi,
I just want to point out a discrepancy between the documentation of predict.nnet & the function definition.
>?predict.nnet =>
predict.nnet package:nnet R Documentation
Predict New Examples by a Trained Neural Net
Description:
Predict new examples by a trained neural net.
Usage:
predict.nnet(object, x,
2005 Sep 09
0
usage of the trianed networks by nnet without R enviromen t
One possibility is to look at predict.nnet(), and
- Write an R function that write out parts of an nnet object that are needed
by predict.nnet() to an external file.
- Re-write predict.nnet() in C, reading the model information from the
external file. Obviously you'll also need the C source for the code that
predict.nnet() calls, and modify those as needed to strip out dependency on
R, if
2006 Feb 02
0
problem with nnet
Hello All,
I am working with samr and nnet packages.
I am following the steps given below:
1> I take a input file with signal values for 9506 genes and 36 chips
, belonging to two classes.
2> I perform samr analysis on 80% of chip data from both the
classes.(selected by random sampling)
3> I then use the data of only the significant genes from this samr
analysis to train nnet.
4>
2006 Mar 10
1
need help in tune.nnet
Dear R people,
I want to use the tune.nnet function of e1071 package to tune nnet .
I am unable to understand the parameters of tune.nnet from the e1071 pdf
document.
I have performed nnet on a traindata and want to test it for class
prediction with a testdata.
I want to know the values of size,decay,range etc. parameters for which
the prediction of testdata is best.
Can anyone please tell me
2010 Oct 12
1
need help with nnet
HI, Dear R community,
My data set has 2409 variables, the last one is response variable. I have
used the nnet after feature selection and works. But this time, I am using
nnet to fit a model without feature selection. I got the following error
information:
> dim(train)
[1] 1827 2409
nnet.fit<-nnet(as.factor(out) ~ ., data=train, size=3, rang=0.3,
decay=5e-4, maxit=500) # model
2016 Aug 18
0
Nested KVM issue
I've tried with KSM disabled and nothing changed.
I've upgraded KVM to qemu-kvm-ev. I'm waiting to see if there are any
improvements and report back.
?n mie., 17 aug. 2016 la 15:10, Boris Derzhavets <bderzhavets at hotmail.com>
a scris:
> For myself KSM is unpredictable feature. The problem is Compute, just this
> node
>
> does "copy on write" , so only
2016 Aug 17
2
Nested KVM issue
For myself KSM is unpredictable feature. The problem is Compute, just this node
does "copy on write" , so only Compute.
My concern exactly is where would it lead to worse or better Guest behavior ?
I am not expecting complete fix. I would track via top/htop and dmesg via Cron on 1-2 hr
period.
________________________________
From: centos-virt-bounces at centos.org
2009 Jul 24
1
nnet library and FANN package'm
Hello !
I'd like to know to which of the FANN package network corresponds the R nnet
network ?
In more details, what is the R nnet activation function, what is the
training algorithm (rprop, quickprop, ...) ? Also, it seems that the R nnet
"decay" parameter in nnet corresponds to the "learning_rate" parameter in
FANN. Correct ?
Many thanks in advance !
Luc Moulinier
2016 Aug 17
0
Nested KVM issue
Both baremetal and compute ? Are there any other metrics do you consider
useful to collect for troubleshooting purposes ?
?n mie., 17 aug. 2016 la 13:04, Boris Derzhavets <bderzhavets at hotmail.com>
a scris:
> It sounds weird, but attempt to disable KSM and see would it help or no ?
>
>
> ------------------------------
> *From:* centos-virt-bounces at centos.org
2009 Nov 02
1
modifying predict.nnet() to function with errorest()
Greetings,
I am having trouble calculating artificial neural network
misclassification errors using errorest() from the ipred package.
I have had no problems estimating the values with randomForest()
or svm(), but can't seem to get it to work with nnet(). I believe
this is due to the output of the predict.nnet() function within
cv.factor(). Below is a quick example of the problem I'm
2010 Jan 29
0
Help interpreting libarary(nnet) script output..URGENT
Hello,
I am pretty new to R. I am working on neural network classifiers and I am
feeding the nnet input from different regions of interest (fMRI data). The
script that I am using is this:
library (MASS)
heap_lda <-
data.frame(as.matrix(t(read.table(file="R_10_5runs_matrix9.txt")))*100000,syll
= c(rep("heap",3),rep("hoop",3),rep("hop",3)))
library(nnet)