有人知道"boxconstraint" of function "svmtrain"?
网站写:
Value of the box constraint C for the soft margin. C can be a scalar, or a
vector of the same length as the training data.
If C is a scalar, it is automatically rescaled by N/(2*N1) for the data
points of group one and by N/(2*N2) for the data points of group two, where
N1 is the number of elements in group one, N2 is the number of elements in
group two, and N = N1 + N2. This rescaling is done to take into account
unbalanced groups, that is cases where N1 and N2 have very different values.
If C is an array, then each array element is taken as a box constraint for
the data point with the same index.
但我有问题
1. group one 指的是归类于 0 还是 1的class?
2. 如果按照网站的定义的话 1<C<无限
但为什么能设为0.1?