 A number of different proposals have been made in this regard (Anderson, 1991; Griffiths, Canini, Sanborn & Navarro, 2007; Love, Medin & Gureckis, 2004; Vanpaemel & Storms, 2008).These models can be regarded as providing a compromise between exemplar and prototype models.The basic idea of explanation-based learning suggests that a new concept is acquired by experiencing examples of it and forming a basic outline.