The representation of artificial dataset with three main classes, .

<p>To demonstrate how different parts of a class overlap with other classes in different feature spaces, Class 1 is splited to four parts and positions of these parts in the three feature spaces are shown in a) first feature space, b) second feature space and c) third feature space. This figure is inspired from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0084341#pone.0084341-Tabassian1" target="_blank">[29]</a>.