As mentioned above, SBTSVM and BBTSVM can separate classes
from the nodes of binary tree. However, the processing is random,
indicating that we do not know which classes are separated first.
Therefore, the separabilitymeasure should be calculated for the constructed
BT.
In order to reduce the classification error in the root node, the
class with long distance should be classified firstly. In general, hyperspectral
image has massive bands with abundance of information.
There are many separability rules as follows: average distance between
samples, relative distance between samples, and discrete degree,
etc. If the samples have same distance between different
classes or different distance appears in the same classes, the average
distance cannot measure the separability. Relative distance also is of