“…In recent years, pattern classification techniques such as support vector machines, 21,22 random forests, 14 and backpropagation neural networks 14,23 have been actively investigated and applied to computer-aided medical diagnosis, 14,24,25 human face recognition, 26,27 and other applications. 24,28,29 These classifier-based approaches typically require balanced (approximately equal number of) positive and negative training samples to derive reliable decision rules for properly separating the sample space.…”