search for: cjlin

Hi all, I am using the "svm" command in the e1071 package. Does it have an automatic way of setting the "cost" parameter? I changed a few values for the "cost" parameter but I hope there is a systematic way of obtaining the best "cost" value. I noticed that there is a "cross" (Cross validation) parameter in the "svm" function. But I

Hi, the new version 1.1-0 of package e1071 is now on CRAN. Changes: *) use libsvm 2.1 for support vector machines. We are now also a kind of ``official'' R frontend to libsvm and linked from their homepage at http://www.csie.ntu.edu.tw/~cjlin/libsvm *) new functions for comparing partitions Best, Fritz -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-announce mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in th...

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

I'm not sure what the parameter specifies: random if an integer value is specified, random parameter vectors are drawn from the parameter space. What are the parameter vectors and what is the parameter space? What means drawn? greetings Jessi [[alternative HTML version deleted]]

I'm running SVM from e1071 package on a data with ~150 columns (variables) and 50000 lines of data (it takes a bit of time) for radial kernel for different gamma and cost values. I get a very large models with at least 30000 vectors and the prediction I get is not the best one. What does it mean and what could I do to ameliorate my model ? Jerzy Orlowski

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

Dear all, I am currently looking for a book about support vector machines for regression and classification and am a bit lost since they are plenty of books dealing with this subject. I am not totally new to the field and would like to get more information on that subject for later use with the e1071 <http://cran.r-project.org/web/packages/e1071/index.html> package for instance. Does

...istical parameters (i.e., cross-validation R2, pred R2 etc). now, I can do GA+svm to do variable selection and build the models and get some statistical paramets depicted above. GA: matlab GA toolbox (http://www.sheffield.ac.uk/acse/research/ecrg/gat.html) svm: libsvm (http://www.csie.ntu.edu.tw/~cjlin/libsvm/) now I want to know, how to get the predicted values : In libsvm for example: cmd = ['-v ',num2str(v),' -c',num2str(cgp(nind,1)), '-g ',num2str(cgp(nind,2)),' -p ',num2str(cgp(nind,3)),' -s 3']; model = svmtrain(train_y,train_data_best,cmd); train_...

...Recursive Feature Elimination for my feature-selection part. On 1/5/06, Weiwei Shi <helprhelp at gmail.com> wrote: > > FYI: > > check the following paper on svm (using libsvm) as well as random > forest in the context of feature selection. > > http://www.csie.ntu.edu.tw/~cjlin/papers/features.pdf > > HTH > > On 1/4/06, Diaz.Ramon <rdiaz at cnio.es> wrote: > > Dear Frank, > > I expect you'll get many different answers since a wide variety of > approaches have been suggested. So I'll stick to self-advertisment: I've > written...

Hi All, Sorry if this is a repost (a quick browse didn't give me the answer). I wonder if there are packages that can do the feature selection and classification at the same time. For instance, I am using SVM to classify my samples, but it's easy to get overfitted if using all of the features. Thus, it is necessary to select "good" features to build an optimum hyperplane (?).

...istical parameters (i.e., cross-validation R2, pred R2 etc). now, I can do GA+svm to do variable selection and build the models and get some statistical paramets depicted above. GA: matlab GA toolbox (http://www.sheffield.ac.uk/acse/research/ecrg/gat.html) svm: libsvm (http://www.csie.ntu.edu.tw/~cjlin/libsvm/<http://www.csie.ntu.edu.tw/%7Ecjlin/libsvm/> ) now I want to know, how to get the predicted values : In libsvm for example: cmd = ['-v ',num2str(v),' -c',num2str(cgp(nind,1)), '-g ',num2str(cgp(nind,2)),' -p ',num2str(cgp(nind,3)),' -s 3']; m...