Displaying 20 results from an estimated 10000 matches similar to: "reading svm function in e1071"
2005 Jan 14
2
probabilty calculation in SVM
Hi All,
In package e1071 for SVM based classification, one can get a probability
measure for each prediction. I like to know what is method that is used for
calculating this probability. Is it calculated using logistic link function?
Thanks for your help.
Regards,
Raj
2012 Dec 02
1
e1071 SVM: Cross-validation error confusion matrix
Hi,
I ran two svm models in R e1071 package: the first without cross-validation
and the second with 10-fold cross-validation.
I used the following syntax:
#Model 1: Without cross-validation:
> svm.model <- svm(Response ~ ., data=data.df, type="C-classification",
> kernel="linear", cost=1)
> predict <- fitted(svm.model)
> cm <- table(predict,
2007 Sep 25
1
10- fold cross validation for naive bayes(e1071)
Hallo!
I would need a code for 10-fold cross validation for the classifiers Naive Bayes and svm (e1071) package. Has there already been done something like that?
I tried to do it myself by applying the tune function first:
library(e1071)
tune.control <- tune.control(random =F, nrepeat=1, repeat.aggregate=min.,sampling=c("cross"),sampling.aggregate=mean, cross=10, best.model=T,
2006 Jan 18
2
Help with plot.svm from e1071
Hi.
I'm trying to plot a pair of intertwined spirals and an svm that
separates them. I'm having some trouble. Here's what I tried.
> library(mlbench)
> library(e1071)
Loading required package: class
> raw <- mlbench.spirals(200,2)
> spiral <- data.frame(class=as.factor(raw$classes), x=raw$x[,1], y=raw$x[,2])
> m <- svm(class~., data=spiral)
> plot(m,
2006 Jan 27
3
e1071: using svm with sparse matrices (PR#8527)
Full_Name: Julien Gagneur
Version: 2.2.1
OS: Linux (Suse 9.3)
Submission from: (NULL) (194.94.44.4)
Using the SparseM library (SparseM_0.66)
and the e1071 library (e1071_1.5-12)
I fail using svm method with a sparse matrix. Here is a sample example.
I experienced the same problem under Windows.
> library(SparseM)
[1] "SparseM library loaded"
> library("e1071")
2010 Apr 06
3
svm of e1071 package
Hello List,
I am having a great trouble using svm function in e1071 package. I have 4gb of data that i want to use to train svm. I am using Amazon cloud, my Amazon Machine Image(AMI) has 34.2 GB of memory. my R process was killed several times when i tried to use 4GB of data for svm. Now I am using a subset of that data and it is only 1.4 GB. i remove all unnecessary objects before calling
2001 Nov 20
2
segfault using svm from e1071 (PR#1178)
This could be a bug in the e1071 svm code, but maybe not -- I guess I'll
send it here anyway. It's reproducible.
> x <- seq (0.1,5,by=0.05)
> y <- log(x) + rnorm (x, sd=0.2)
> library(e1071)
> m <- svm (x,y)
Process R segmentation fault at Tue Nov 20 23:34:19 2001
> version
_
platform i686-pc-linux-gnu
arch i686
os
2012 Mar 02
1
e1071 SVM: Cross-validation error confusion matrix
Hi,
I ran two svm models in R e1071 package: the first without cross-validation
and the second with 10-fold cross-validation.
I used the following syntax:
#Model 1: Without cross-validation:
> svm.model <- svm(Response ~ ., data=data.df, type="C-classification",
> kernel="linear", cost=1)
> predict <- fitted(svm.model)
> cm <- table(predict,
2010 May 14
4
Categorical Predictors for SVM (e1071)
Dear all,
I have a question about using categorical predictors for SVM, using "svm"
from library(e1071). If I have multiple categorical predictors, should they
just be included as factors? Take a simple artificial data example:
x1<-rnorm(500)
x2<-rnorm(500)
#Categorical Predictor 1, with 5 levels
x3<-as.factor(rep(c(1,2,3,4,5),c(50,150,130,70,100)))
#Catgegorical Predictor
2010 Nov 23
5
cross validation using e1071:SVM
Hi everyone
I am trying to do cross validation (10 fold CV) by using e1071:svm method. I
know that there is an option (?cross?) for cross validation but still I
wanted to make a function to Generate cross-validation indices using pls:
cvsegments method.
#####################################################################
Code (at the end) Is working fine but sometime caret:confusionMatrix
2010 Jul 14
1
question about SVM in e1071
Hi,
I have a question about the parameter C (cost) in svm function in e1071. I
thought larger C is prone to overfitting than smaller C, and hence leads to
more support vectors. However, using the Wisconsin breast cancer example on
the link:
http://planatscher.net/svmtut/svmtut.html
I found that the largest cost have fewest support vectors, which is contrary
to what I think. please see the scripts
2011 Jan 13
1
question about svm(e1071)
Dear all,
I executed svm calculation using e1071 library with a microarray data (http://www.iu.a.u-tokyo.ac.jp/~kadota/R/data_Singh_RMA_3274.txt).
Then, I shuffled the data samples and executed svm calculation again.
The results of 2 calculation were different (in SV, coefs and weights).
I attached the script below. Could please tell me why this happens?
If possible please tell me how to make
2005 Jun 29
2
Running SVM {e1071}
Dear David, Dear Friends,
After any running svm I receive different results of Error estimation of 'svm' using 10-fold cross validation. What is the reason ? It is caused by the algorithm, libsvm , e1071 or something els? Which value can be optimal one ? How much run can reach to the optimality.And finally, what is difference between Error estimation of svm using 10-fold cross validation
2012 Mar 14
1
How to use a saved SVM model from e1071
Hello,
I have an SVM model previously calibrated using libsvm R implementation from
the e1071 package.
I would like to use this SVM to predict values, from a Java program.
I first tried to use jlibsvm and the "standard" java implementation of
libsvm, without success.
Thus, I am now considering writing data in files from my Java code, calling
an R program to predict values, then gather
2009 Jul 07
2
Question in using e1071 svm routine
Hi all,
I've got the following error message in using e1071 svm routine...
Could anybody please help me?
Thank you!
---------------------------------
model <- svm(y=factor(mytraindata[, 1]), x=mytraindata[, -1], probability=T)
Error in if (any(co)) { : missing value where TRUE/FALSE needed
In addition: Warning message:
In FUN(newX[, i], ...) : NAs introduced by coercion
2003 Dec 10
3
e1071:svm - default epsilon = 0.1 (NOT 0.5) (PR#5671)
In e1071 package/svm default epsilon value is set to 0.1 and not 0.5
as documentation says.
R
2004 Dec 18
1
erro in SVM (packsge "e1071")
Hello,
I am using SVM under e1071 package for nu-regression with 18 parameters. The
variables are ordered factors, factors, date or numeric datatypes. I use the
linear kernel.
It gives the following error that I cannot solve. I tryed debug, browser and
all that stuff, but no way.
The error is:
Error in get(ctr, mode = "function", envir = parent.frame())(levels(x), :
2010 Jul 09
1
interpretation of svm models with the e1071 package
Dear all,
after having calibrated a svm model through the svm() command of the
e1071 package, is there a way to
i) represent the modeled relationships between the y and X variables
(response variable vs. predictors)?
ii) rank the influence of the predictors used in the model?
Right now I am more interested in regression models, but I guess this
would be useful for classification too.
Thank
2011 May 25
1
help with tune.svm() e1071
Hi,
I am trying to use tune.svm in e1071 package.
the command i use is
tobj <- tune.svm(labels, data= data, cost = 10^(1:2))
Should the last column of the 'data' contain the labels as well? I want to
use the linear kernel. But it gives me the error
"Error in model.frame.default(formula, data) : 'data' must be a data.frame,
not a matrix or an array"
Do you know why
2009 Apr 10
1
Built-in Code behind SVM
Hi R,
I need to see the inner code behind the function "svm" in the package
e1071. I enter svm in the console and get the below output.
> svm
function (x, ...)
UseMethod("svm")
<environment: namespace:e1071>
Is there any way I can look into the code of what svm (support vector
machine) is doing?
Thanks a lot for your help...
Thanks and Regards,