Displaying 20 results from an estimated 4000 matches similar to: "nnet learning"
2005 Mar 09
1
nnet abstol
Hi,
I am using nnet to learn transfer functions. For each transfer function I can estimate the best possible Mean Squared Error (MSE). So, rather than trying to grind the MSE to 0, I would like to use abstol to stop training once the best MSE is reached.
Can anyone confirm that the abstol parameter in the nnet function is the MSE, or is it the Sum-of-Squares (SSE)?
Best regards,
Sam.
2006 Nov 30
0
Preventing early stopping in neural network (nnet package)
Hello there,
I'm back again with another question about the neural network
package. I'm having trouble getting the network to run for the
maximum number of iterations. It always stops early, usually after
100 iterations claiming to have converged at an answer.
Now, for my purposes I want it to run for the entire number of
epochs, and I'm been looking at modifying the abstol
2005 Apr 13
0
abstol in nnet
Hello All,
I would like to know what fit criterion (abstol arg)
is in nnet. Is it the threshold for the difference btw
the max output and target values?
Is the value at each iteration also the difference btw
max of output and target values over all output units
(case of multiple classes)?
How could value displayed at each iteration be related
to SSE and abstol be related to threshold SSE,
2007 Jan 28
2
nnet question
Hello,
I use nnet to do prediction for a continuous variable.
after that, I calculate correlation coefficient between predicted value and
real observation.
I run my code(see following) several time, but I get different correlation
coefficient each time.
Anyone know why?
In addition, How to calculate prediction accuracy for prediction of
continuous variable?
Aimin
thanks,
> m.nn.omega
2006 Nov 22
1
What training algorithm does nnet package use?
Greetings list,
I've just swapped from the "neural" package to the "nnet" package and
I've noticed that the training is orders of magnitude faster, and the
results are way more accurate.
This leads me to wonder, what training algorithm is "nnet" using? Is
it a modification on the standard backpropagation? Or a completely
different algorithm? I'm
2000 Jul 22
1
maketitle garbles the title in package nnet (PR#613)
The TITLE for the nnet package is garbled: it comes out as
nnet Feed-forward neural networks and multinomial log-linear
nnet Feed-forward neural networks and multinomial log-linear models
The problem is in maketitle:
auk% cat DESCRIPTION
Bundle: VR
Version: 6.1-9
Date: 2000/07/11
Depends: R (>= 1.1)
Author: S original by Venables & Ripley.
R port by Brian Ripley
2003 Aug 19
3
On the Use of the nnet Library
Dear List,
I am trying to solve a problem by the neural network method(library:
nnet). The problem is to express Weight in terms of Age , Sex and Height
for twenty people. The data frame consists of 20 observations with four
variables: Sex, Age, Height and Weight. Sex is treated as a factor, Age
and Weight are variables normalized to unity, as usual. I wanted to
construct a neural network, and so
2010 Dec 10
2
Need help on nnet
Hi,
Am working on neural network.
Below is the coding and the output
> library (nnet)
> uplift.nn<-nnet (PVU~ConsumerValue+Duration+PromoVolShare,y,size=3)
# weights: 16
initial value 4068.052704
final value 3434.194253
converged
> summary (uplift.nn)
a 3-3-1 network with 16 weights
options were -
b->h1 i1->h1 i2->h1 i3->h1
16.64 6.62 149.93
2009 Feb 18
1
Training nnet in two ways, trying to understand the performance difference - with (i hope!) commented, minimal, self-contained, reproducible code
Dear all,
Objective: I am trying to learn about neural networks. I want to see
if i can train an artificial neural network model to discriminate
between spam and nonspam emails.
Problem: I created my own model (example 1 below) and got an error of
about 7.7%. I created the same model using the Rattle package (example
2 below, based on rattles log script) and got a much better error of
about
2005 Jul 22
2
about nnet package
Dear All,
I'm learning to train a neural network with my training data by using nnet package, then evaluate it with a evaluation set. My problem here is that, I need the trained network to be used in future, so, what should I store? and How? Any other options other than nnet package? Any example will be highly appreciated!
Best,
Baoqiang Cao
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
2010 Jun 02
1
nnet: cannot coerce class c("terms", "formula") into a data.frame
Dearest all,
Objective: I am now learning neural networks. I want to see how well can
train an artificial neural network model to discriminate between the two
files I am attaching with this message.
http://r.789695.n4.nabble.com/file/n2240582/3dMaskDump.txt 3dMaskDump.txt
http://r.789695.n4.nabble.com/file/n2240582/test_vowels.txt test_vowels.txt
Question: when I am attempting to run
2009 Mar 10
1
find the important inputs to the neural network model in "nnet" package
Hi, I have a binary variable and many explanatory variables and I want to
use the package "nnet" to model these data, (instead of logistic regression).
I want to find the more effective variables (inputs to the network) in
the neural network model. how can I do this?
thanks.
[[alternative HTML version deleted]]
2003 Oct 20
2
nnet behaving oddly
Hi,
I was trying to use the nnet library and am not sure of whats going
on. I am calling the nnet function as:
n <- nnet(x,y,size=3,subset=sets[[1]], maxit=200)
Where x is a 272x4 matrix of observations (examples) and y is a 272x1
matrix of target values. However when I look at nnet$residuals they are
off by two orders of magnitude (compared to the output from neural
network code that I
2006 Jun 17
1
Getting forcasting equation from nnet results
I'm trying to build forecasting equation from weights of 2-2-1 neural net.
Running the nnet function gives me a vecto of 9 weights, but I don't know how
to build the equation form these values.
Can anyone advice? Or at least tell me where the nnet output is described in
details (the manual only gives a brief description).
Thanks.
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
2008 Dec 29
1
How to get unique solution from nnet function
Hi R,
I am using nnet function of nnet package to fit neural networks. Now I want to get a unique solution every time I run the function for the same data. If I give rang=0, it solves my problem but I am not sure whether I am doing the right thing. Any comments are welcome.
Thank you,
Regards
Utkarsh Singhal | Amba Research
Ph +91 80 3980 8017 | Mob +91 99 0295 8815
Bangalore * Colombo
2004 Jun 14
2
CVnn2 + nnet question
Hi,
I am trying to determine the number of units in the hidden layer
and the decay rate using the CVnn2 script found in MASS directory
(reference: pg 348,MASS-4).
The model that I am using is in the form of Y ~ X1 + X2 + X3...
+ X11 and the underlying data is time-series in nature.
I found the MASS and nnet package extremely useful (many thanks
to the contributors).
However I am getting
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)
2003 May 25
1
Example Data Set(s) for nnet, rpart
Hi,
I'm doing a presentation on Neural Networks and Tree-Based Models in two
weeks, at the moment I'm looking for a data set to use in the
presentation. What I would like to use is a good old data, like the Iris
data, that is already known by every statisticians.
MASS4 uses the cpus data in Chapter 8.10 and the Cushing's syndrome in
Chapter 12.4. These two data sets plus the