“…I N MANY real-world applications such as pattern recognition, data mining, and time-series prediction, we often confront difficult situations where a complete set of training samples is not given when constructing a system. In face recognition, for example, since human faces have large variations due to expressions, lighting conditions, makeup, hairstyles, and so forth, it is hard to consider all variations of face in advance [6], [31], [35]. In many cases, training samples are provided only when a system misclassifies objects; hence the system is learned online to improve the classification performance.…”