Displaying 20 results from an estimated 10000 matches similar to: "decision values and probability in SVM"
2004 Dec 16
2
reading svm function in e1071
Hi,
If I try to read the codes of functions in e1071 package, it gives me following error message.
>library(e1071)
> svm
function (x, ...)
UseMethod("svm")
<environment: namespace:e1071>
> predict.svm
Error: Object "predict.svm" not found
>
Can someone help me on this how to read the codes of the functions in the e1071 package?
Thanks.
Raj
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
2017 Sep 02
0
problem in testing data with e1071 package (SVM Multiclass)
Hello all,
this is the first time I'm using R and e1071 package and SVM multiclass
(and I'm not a statistician)! I'm very confused, then. The goal is: I
have a sentence with sunny; it will be classified as "yes" sentence; I
have a sentence with cloud, it will be classified as "maybe"; I have a
sentence with rainy il will be classified as "no".
The
2017 Jul 06
0
svm.formula versus svm.default - different results
Dear community,
I'm performing svm-regression with svm at library e1071.
As I wrote in another post: "svm e1071 call - different results", I get different results if I use the svm.default rather than the svm.formula, being better the ones at svm.formula
I've debugged both options.
While debugging the svm.formula, I've seen that when I reach the call:
ret <-
2010 Aug 18
1
probabilities from predict.svm
Dear R Community-
I am a new user of support vector machines for species distribution modeling and am using package e1071 to run svm() and predict.svm(). Briefly, I want to create an svm model for classification of a factor response (species presence or absence) based on climate predictor variables. I have used a training dataset to train the model, and tested it against a validation data set
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
2009 May 11
1
Problems to run SVM regression with e1071
Hi R users,
I'm trying to run a SVM - regression using e1071 package but the function svm() all the time apply a classification method rather than a regression.
svm.m1 <- svm(st ~ ., data = train, cost = 1000, gamma = 1e-03)
Parameters:
SVM-Type: C-classification
SVM-Kernel: radial
cost: 1000
gamma: 0.001
Number of Support Vectors: 209
2010 Jun 29
2
Need help for SVM code for microarray classification
Hi I am Aadhithya I am trying to write a code to classify microarray data
(AML and ALL) using SVM in R
my code goes like this :
library(e1071)
train<-read.table("Z:/Documents/train.txt",header=T);
test<-read.table("Z:/Documents/test.txt",header=T);
cl <- c(c(rep("ALL",10), rep("AML",10)));
model<- svm(train,cl);
pred <-
2010 Apr 29
2
can not print probabilities in svm of e1071
> x <- train[,c( 2:18, 20:21, 24, 27:31)]
> y <- train$out
>
> svm.pr <- svm(x, y, probability = TRUE, method="C-classification",
kernel="radial", cost=bestc, gamma=bestg, cross=10)
>
> pred <- predict(svm.pr, valid[,c( 2:18, 20:21, 24, 27:31)],
decision.values = TRUE, probability = TRUE)
> attr(pred, "decision.values")[1:4,]
2011 Feb 18
1
segfault during example(svm)
If do:
> library("e1071")
> example(svm)
I get:
svm> data(iris)
svm> attach(iris)
svm> ## classification mode
svm> # default with factor response:
svm> model <- svm(Species ~ ., data = iris)
svm> # alternatively the traditional interface:
svm> x <- subset(iris, select = -Species)
svm> y <- Species
svm> model <- svm(x, y)
svm>
2009 Oct 21
2
SVM probability output variation
Dear R:ers,
I'm using the svm from the e1071 package to train a model with the
option "probabilities = TRUE". I then use "predict" with "probabilities
= TRUE" and get the probabilities for the data point belonging to either
class. So far all is well.
My question is why I get different results each time I train the model,
although I use exactly the same data.
2009 Sep 06
2
Regarding SVM using R
Hi Abbas,
Before I try to give you answers, I just want to mention that you
should send R related reqests to the R-help list, and not me
personally because (i) there's a greater likelihood that it will get
answered in a timely manner, and (ii) people who might have a similar
problem down the road might benefit from any answer via searching the
list archives ... anyway:
On Sep 5, 2009, at
2006 Aug 04
0
training svm's with probability flag
Hi-
I'm seeing some weirdness with svm and tune.svm that I can't figure out- was
wondering if anyone else has seen this? Perhaps I'm failing to make
something the expected class?
Below is my repro case, though it *sometimes* doesn't repro. I'm using
R2.3.1 on WindowsXP. I was also seeing it happen with R2.1.1 and have seen
it on 2 different machines.
data(iris)
attach(iris)
2006 Aug 04
0
training svm's with probability flag (re-send in plain text)
Hi-
I'm seeing some weirdness with svm and tune.svm that I can't figure out- was
wondering if anyone else has seen this? Perhaps I'm failing to make
something the expected class?
Below is my repro case, though it *sometimes* doesn't repro. I'm using
R2.3.1 on WindowsXP. I was also seeing it happen with R2.1.1 and have seen
it on 2 different machines.
data(iris)
attach(iris)
2011 Jul 24
0
repeated execution of svm(e1071) gives different results, if probability = TRUE is set
Hello, Connoisseurs!
Please explain to novices, why svm model gives different results in the
loop with the same data? As a result, I can not find the best gamma and
cost parameters. Also tune.svm yields results that can not be repeated.
How can I avoid this?
My sessionInfo:
R version 2.11.1 (2010-05-31)
x86_64-pc-linux-gnu
locale:
[1] LC_CTYPE=en_US.UTF-8 LC_NUMERIC=C
2011 Sep 13
0
Help in SVM prediction
Hello,
I am trying to use SVM from e1071 package for doing binary classification
and I am having problems in prediction using SVM. I ran a SVM for
X~as.factor(X1)+as.factor(X2)+as.factor(X3),data=data1,cross=10.
str(data1) gives me
data.frame': 5040 obs. of 5 variables:
$ X4: int 1 2 3 4 5 6 7 8 9 10 ...
$ X : int 0 1 0 1 0 0 1 1 1 1 ...
$ X2: int 1 8 15 18 1 14 10 9 8 8 ...
$ X3
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,
2011 Feb 23
0
svm(e1071) and scaling of weights
I expected, that I will get the same prediction, if I multiply the
weights for all classes with a constant factor, but I got different
results. Please look for the following code.
> library(e1071)
> data(Glass, package = "mlbench")
> index <- 1:nrow(Glass)
> testindex <- sample(index, trunc(length(index)/5))
> testset <- Glass[testindex, ]
> trainset <-
2013 Jan 15
0
e1071 SVM, cross-validation and overfitting
I am accustomed to the LIBSVM package, which provides cross-validation
on training with the -v option
% svm-train -v 5 ...
This does 5 fold cross validation while building the model and avoids
over-fitting.
But I don't see how to accomplish that in the e1071 package. (I
learned that svm(... cross=5 ...) only _tests_ using cross-validation
-- it doesn't affect the training.) Can
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