similar to: Neural Network

Displaying 20 results from an estimated 200 matches similar to: "Neural Network"

2014 Jan 13
1
Ayuda con Neuralnet
Hola a todos, en primer lugar quería agradecer la ayuda recibida desde el foro con respecto a la creación de una red neuronal. Estoy utilizando el paquete Neuralnet, que me parece que es bastante bueno, pero tengo el problema que soy incapaz de hacer las predicciones del modelo. Sé que se hace con el comando "compute", pero no encuentro ningún ejemplo de cómo hacerlo. ¿Alguien me puede
2011 Jun 24
3
Fwd: Extract element of a list based on an index value
> Dear list, > > I have some data on a geneaology, here is a subset: > warmerge[1:11,c(1,6,25)] > Warrior SibID birth.year > 1100 3793 2013 1926 > 4 2013 2024 1934 > 1094 3769 2024 1918 > 632 2747 2037 1928 > 176 2083 2039 1944 > 187 2085 2039 1949 > 192 2086 2039 NA > 495
2008 Jul 16
4
Likelihood ratio test between glm and glmer fits
Dear list, I am fitting a logistic multi-level regression model and need to test the difference between the ordinary logistic regression from a glm() fit and the mixed effects fit from glmer(), basically I want to do a likelihood ratio test between the two fits. The data are like this: My outcome is a (1,0) for health status, I have several (1,0) dummy variables RURAL, SMOKE, DRINK, EMPLOYED,
2013 May 20
0
Neural network: Amore adaptative vs batch why the results are so different?
I am using the iris example came with nnet package to test AMORE. I can see the outcomes are similar to nnet with adaptative gradient descent. However, when I changed the method in the newff to the batch gradient descent, even by setting the epoch numbers very large, I still found all the iris expected class=2 being classified as class=3. In addition, all those records in the outcomes (y) are the
2013 Mar 27
0
A simple perceptron neural network (nnet)
can u explain me, how it works your code??? please. i´m also doing a simple perceptron for homework on R and i dont know where to start. [[alternative HTML version deleted]]
2004 Jul 11
0
Neural Net and SNOW
Hello R masteRs, I was wondering if somebody had already implemented a parallel version of the function Nnet (with the SNOW package for instance) and would be willing to share a few pointers on how to achieve it. I have a training set of dimensions 905,000 X 5. Should I just get more RAM and run the nnet on one procesor? Or is there a slick way to parallelize the computations? I have tried to
2009 Apr 18
1
Neural Networks in R - Query
Dear R users, I'd like to ask your guidance regarding the following two questions: (i) I just finished reading Chris Bishop's book "Neural Networks for Pattern Recognition". Although the book gave me good theoretical foundation about NN, I'm now looking for something more practical regarding architecture selection strategies. Is there any good reference about "best
2010 Jan 03
2
Artificial Neural Networks
Hi! I am studying to use some R libraries which are applied for working with artificial neural neworks (amore, nnet). Can you recommend some useful, reliable and easy to get example data to use in R for creating and testing a neural network? __________________________________________________________________ Make your browsing faster, safer, and easier with the new Internet
2009 Jul 18
0
classification task with RBF neural networks
Hello everybody, I'm looking for a way to build an RBF classification network with R but I can't find any. I know there is the 'neural' package, but apparently the RBF networks I can build with that are for approximation tasks only. Is there any package I can use to build an RBF network for a classification task? I've also looked on CRAN but couldn't find any. Thank you for
2010 Jul 13
0
Neural Network package AMORE and a weight decay
Hi, I want to use the neural network package AMORE and I don't find in the documentation the weight decay option. Could someone tell if it is possible to add a regularization parameter (also known as a weight decay) to the training method. Is it possible to alter the gradient descent rule for that? Thanks, Ron
2003 Sep 22
0
Neural Network Question
Hi, I'm using the R nnet package to train a classifier to recognise items which belong to a particular class and those which don't belong to the class. I'm supplying nnet with a matrix x containing training examples (in each row) and a matrix y of targets. The training set is made up of 200 positive examples and 1000 negative examples. I want to train the network on the same
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
2011 May 11
0
Init nnetTs (or nnet?) with a former Neural Net
I am new to R and use nnetTs - calls. If a time series of let's say 80000 Datapoints and did call nnetTs I want make a new net for the old ponts plus the next 1000 points (81000 datapoints total) what would again cost much calculation time. So I want to pre-init the new net with the former wonnen net to reduce the necessary iteration numbers. Is thee a possibility to do that and how? i.e.:
2004 Aug 01
1
Neural Net Validation Sub Set
Dear R users, I have been playing with the nnet and predict.nnet functions and have two questions. 1) Is it possible to specify a validation set as well as a training set in the nnet function before using predict.nnet to test the nnet object against new data? 2) Is it possible to specify more than one layer of neurons? Thanks in advance Matt Oliver
2007 Jul 15
0
neural networks function in R
Hi all gurus, I have a few general questions about using neural networks function, i.e. the nnet function. I'm new to this function and still exploring it. So please kindly bear with me. Here are my questions. 1. Is there anyway that I can specify my own objective or loss function for my neural networks? I see that by arguments that we can pass into the networks, we have either square loss
2010 Jan 07
0
building a neural network on a unbalanced data set on R
Hello everybody, I work in a production plant as an operations analyst. I have been using R for two years, starting with my final dissertation project at college. We have the following problem in our plant. At the end of the production process, each joint (that is what we produce) must pass a final electrical test. The result can be 0 or 1. We think that this may depend on some raw
2013 May 17
0
[R-pkgs] Probabilistic neural network (PNN)
Dear useRs, I am pleased to announce the release of the new package PNN. PNN implements the algorithm proposed by Specht (1990). It is written in the R statistical language. It solves a common problem in automatic learning. Knowing a set of observations described by a vector of quantitative variables, we classify them in a given number of groups. Then, the algorithm is trained with this datasets
2013 May 17
0
Probabilistic neural network (PNN)
Dear useRs, I am pleased to announce the release of the new package PNN. PNN implements the algorithm proposed by Specht (1990). It is written in the R statistical language. It solves a common problem in automatic learning. Knowing a set of observations described by a vector of quantitative variables, we classify them in a given number of groups. Then, the algorithm is trained with this datasets
2010 Jun 17
0
help with neural network nnet package
HI, Dear R community, I am using the nnet to fit a neural network model to do classification on binary target variable (0, 1). I am using the following codes: nnet.fit<-nnet(as.factor(out) ~ ., data=train, size=5, rang=0.3, decay=5e-4, maxit=500) I want to know what is the activation function for the original inputs, is it sigmoid activation function? and what is the output activation
2007 Jul 02
0
How to set constraints on output layer of Neural Networks
Hi, Please bear with me as I never use NN in R before. I have a network whose my output has, says K node. I would like to put a set of constraints on this layer. Indeed, I have two type of constraints. The first type is that their outputs should sum up to one. The second type is monotonic increasing from the first output node to the K-th node. How can I achieve this? Thank you so much in advance.