Krupal Parikh

8 Questions 23 Answers 0 Followers

Questions related from Krupal Parikh

How to verify whether the kernel is positive definite or indefinite?

I am trying some new kernel functions. For some new kernel functions, I have checked the eigen values of corresponding Gram matrix(UCI bench mark data set). The eigen values are positive and...

20 May 2017 1,007 4 View

How do we interpret the output of LIBSVM?

My problem is multiclassification. It has four classes. I know that using one-one algorithm 6 binary classes will be formed and for one to rest algorithm 4 binjary classes will be there. Libsvm is...

02 September 2015 774 18 View

Why do the dimensions for support vector coefficients differ?

My classification problem has 4 classes. If I use inbuilt LIBSVM library in which one-one approach is used, and check the dimension of support vector coefficient ie, model.sv_coef, it is 53 x 3....

02 September 2015 6,591 2 View

How can I get decision function value of svm using libsvm?

I am trying to calculate value of decision function for 4 classification problem. So, calculate sv, which are 178. Then checked the size of sv_coef(alpha*y), which is coming as [178 3], actually...

18 August 2015 1,111 14 View

Why does the probability estimate not meet predict labels in Libsvm output?

I am using Libsvm(3.18) software with MATLAB interface to classify my data which consist of 4 classes. I am using -b 1 option in svmtrain and svmpredict functions. In the output there are 4...

21 July 2015 1,520 7 View

How can I modify kernel functions in LIBSVM?

Hello!, I want to modify the standard kernel functions by Conformal Transformation. i.e. want to use new_kernel=a(x)*k(x,x')*a(x)', where k(x,x') is the standard kernel function of LIBSVM and a(x)...

04 July 2015 8,918 2 View

How can I modify the code of LIBSVM to find distance of a point to the Hyperplane?

Hi, I am using LIBSVM software with MATLAB interface to classify my data which use SVM algorithm. It is giving output for decision values but I want distance from the hyperplane. In FAQ...

01 July 2015 7,066 2 View

What should be the size of my data set?

My work is on multi classification. I am planning to use libsvm initially with RBF kernel.In my dataset there are around 60 features and 5 classes. what should be the proper size of my dataset ? I...

23 April 2015 2,241 3 View