"Multiclass SVM"

ema

Hi,
As we all know that LSVM works on binary classes ,
how does Rapidminder deal with multiclass

for example possible solutions are
one to all
pairwise classification,


which one does rapid miner use

land

Hi Ema,
if you take a look at the binary2multiclass meta operator, there's a parameter to specify the method. You might choose between one vs all or one vs one (pairwise). Additionally there are some more complex, from information theory inspired methods.

If you use the LibSVM, it internally uses one vs all, as far as I know.

Greetings,
  Sebastian

ema

Hi, javascript:void(0);
thank you very much for ur reponse , i used libsvm
so if it has 4 classes
it does one vs all for every class and takes the average am i right?

Thanx in advance

land

Hi Ema,
although I'm not familiar with the internals of the LibSVM, I think this is exactly what it is doing.


Greetings,
  Sebastian