Conducting a mesh search for SVM using LibSVM and GridSearch in WEKA - Fine tune

Question

I want to start a grid search for two different SVM settings using WEKA. I theoretically know what to do, but I cannot determine the exact setting.

Here is what I want to do: Run the following two algorithms. - C-SVC with RBF core. Search grid C = 2 ^ -5 ... 2 ^ 15, Gamma = 2 ^ -15 ... 2 ^ 3. - C-SVC with the Polynominal core. Grid search for C (as above) and degree.

How exactly should I include these parameters in the grid search? Especially, how do I get a range from 2 ^ -5 to 2 ^ 15, and not from -5 to 15 (which would be clear). And what is PLSFilter? I don’t want to run any filters at all ...

Your help will be greatly appreciated!

Thanks a lot, Axel