Hi, Thanks a lot for making me aware of that SVM-Type. I just thought it would give a warning or an error if C-classification wasn't used.
The solution in my real case was to make the response variable a factor, i.e. before I had Y ~ . with Y numeric. If I first converted Y to a factor, i.e. Y <- factor(Y), then everything went fine. Thanks! Cheers, Mikkel. 2010/2/23 Steve Lianoglou <mailinglist.honey...@gmail.com>: > Hi, > > On Tue, Feb 23, 2010 at 2:43 PM, Mikkel Meyer Andersen <r...@mikl.dk> wrote: >> Dear list. >> >> I using the SVM-methods from the e1071, but I can't get the >> probabilities when predicting. >> >> Code: >> x <- matrix(rbinom(100, 10, 0.3), ncol=2) >> y <- apply(x, 1, sum) >> fit <- svm(y ~ x, method = "C-classification", kernel = "radial", >> probability = TRUE) >> predict(fit, x, probability=TRUE) >> >> Here predict doesn't containing any probabilities (not as attributes >> either). Does anybody know what I'm doing wrong or if the package >> contains any bugs? > > Look at your "fit" object, specifically the SVM-Type and notice that > you are actually running eps-regression, even though you try to > specify classification. So the type of "probabilities" you're after > don't really make sense in regression context. > > A "better" posed problem definition will give you what you're after. I > mean, by just running your example code, my y vector has 10 different > (unique) labels (yours maybe different do to your random seed, I > guess) -- but are you really trying to do 10-way classification? > > -steve > > -- > Steve Lianoglou > Graduate Student: Computational Systems Biology > | Memorial Sloan-Kettering Cancer Center > | Weill Medical College of Cornell University > Contact Info: http://cbio.mskcc.org/~lianos/contact > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
