Dear all, I was wondering if someone can help me. I am learning SVM for classification in my research with kernlab package. I want to know about classification performance using Area Under Curve (AUC). I know ROCR package can do this job but I found all example in ROCR package have include prediction, for example, ROCR.hiv {ROCR}. My problem is how to produce prediction in SVM and to find AUC. Here is a simple example: library(MASS) library(kernlab) library(ROCR) pimamodel <- ksvm(type ~ .,data=Pima.tr,type="C-svc",C=10,prob.model=TRUE) pimamodel fitted(pimamodel) pima.pred <- predict(pimamodel, Pima.te[,-8], type="probabilities") pima.pred # try to find AUC #predid.no <- prediction(pima.pred[,1], Pima.te[,8]) #predid.yes <- prediction(pima.pred[,2], Pima.te[,8]) predid <- prediction(pima.pred, Pima.te[,8]) perfid <- performance(predid,"tpr","fpr") perfid.auc <- performance(predid,"auc") perfid.auc Thank you very much for your help. Best wishes, Muhammad Subianto
Hi you need predict.ksvm() function. for more information see The kernlab package here: lib.stat.cmu.edu/R/CRAN/doc/packages/kernlab.pdf cheers, Amir Muhammad Subianto <msubianto@gmail.com> wrote: Dear all, I was wondering if someone can help me. I am learning SVM for classification in my research with kernlab package. I want to know about classification performance using Area Under Curve (AUC). I know ROCR package can do this job but I found all example in ROCR package have include prediction, for example, ROCR.hiv {ROCR}. My problem is how to produce prediction in SVM and to find AUC. Here is a simple example: library(MASS) library(kernlab) library(ROCR) pimamodel <- ksvm(type ~ .,data=Pima.tr,type="C-svc",C=10,prob.model=TRUE) pimamodel fitted(pimamodel) pima.pred <- predict(pimamodel, Pima.te[,-8], type="probabilities") pima.pred # try to find AUC #predid.no <- prediction(pima.pred[,1], Pima.te[,8]) #predid.yes <- prediction(pima.pred[,2], Pima.te[,8]) predid <- prediction(pima.pred, Pima.te[,8]) perfid <- performance(predid,"tpr","fpr") perfid.auc <- performance(predid,"auc") perfid.auc Thank you very much for your help. Best wishes, Muhammad Subianto ______________________________________________ R-help@stat.math.ethz.ch mailing list stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. --------------------------------- [[alternative HTML version deleted]]