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Journal of Convex Analysis 21 (2014), No. 3, 819--831 Copyright Heldermann Verlag 2014 Conic Separation of Finite Sets. II: The Non-Homogeneous Case Annabella Astorino Istituto di Calcolo e Reti ad Alte Prestazioni C.N.R., Dip. di Ingegneria Informatica, Modellistica, Elettronica e Sistemistica, Università della Calabria, 87036 Rende, Italy astorino@icar.cnr.it Manlio Gaudioso Dip. di Ingegneria Informatica, Modellistica, Elettronica e Sistemistica, Università della Calabria, 87036 Rende, Italy gaudioso@dimes.unical.it Alberto Seeger Dept. of Mathematics, University of Avignon, 33 rue Louis Pasteur, 84000 Avignon, France alberto.seeger@univ-avignon.fr [Abstract-pdf] [For part I of this article see this journal 21 (2013), Number 1.]\par We address the issue of separating two finite sets in $\mathbb{R}^n $ by means of a suitable revolution cone $$ \Gamma (z,y,s)= \{x \in \mathbb{R}^n :\, s\,\Vert x-z\Vert - y^T(x-z)=0\}. $$ One has to select the aperture coefficient $s$, the axis $y$, and the apex $z$ in such a way as to meet certain optimal separation criteria. The homogeneous case $z=0$ has been treated in Part I of this work. We now discuss the more general case in which the apex of the cone is allowed to move in a certain region. The non-homogeneous case is structurally more involved and leads to challenging nonconvex nonsmooth optimization problems. Keywords: Conical separation, revolution cone, alternating minimization, DC programming, classification. MSC: 90C26 [ Fulltext-pdf (135 KB)] for subscribers only. |