Tagged Questions

1
vote
2answers
564 views

LibSVM cost weights for unbalanced data doesn't work

I have a data set that number of negative labeled values are 163 times of number of positive labeled values so I have a unbalanced data set. I have tried that: ...
5
votes
1answer
279 views

A priori selection of SVM class weights

I remember seeing/reading somewhere that for multiclass SVMs with unbalanced data, there was a way to determine the class weights from the training data (rather than X validation). Does anyone know ...
3
votes
3answers
745 views

SVM vs. artificial neural network

I have multiclass unbalanced data (4 class with 15% 25% 45% 15% data in each class). Which method is good for classification of such data- SVM or ANN? UPDATE- Let me make the question little more ...
1
vote
1answer
1k views

Best way to handle unbalanced multiclass dataset with SVM

I'm trying to build a prediction model with SVMs on fairly unbalanced data. My labels/output have three classes, positive, neutral and negative. I would say the positive example makes about 10 - 20% ...