Wednesday, May 19, 2010

The coefficients for SVs in decision functions in LIBSVM

For support vector classifications, these coefficients for support vectors are positive originally. In LIBSVM, for some reason, they are returned as the product of the original coefficients and labels. At the first it could be confusing because there is no documentation on it. But it can be found at line 1454 in function static void solve_c_svc(…) in svm.cpp.