Original article at: http://www.math.washington.edu/~ejpecp/ECP/viewarticle.php?id=1685

A note on the richness of convex hulls of VC classes

Gàbor Lugosi, Pompeu Fabra University, Spain
Shahar Mendelson, The Australian National University, Australia
Vladimir Koltchinskii, The University of New Mexico, USA

Abstract

We prove the existence of a class A of subsets of Rd of VC dimension 1 such that the symmetric convex hull F of the class of characteristic functions of sets in A is rich in the following sense. For any absolutely continuous probability measure μ on Rd, measurable set B and ε >0, there exists a function f in F such that the measure of the symmetric difference of B and the set where f is positive is less than ε. The question was motivated by the investigation of the theoretical properties of certain algorithms in machine learning.

Full text: PDF | PostScript




Copyright for articles published in this journal is retained by the authors, with first publication rights granted to the journal. By virtue of their appearance in this open access journal, articles are free to use, with proper attribution, in educational and other non-commercial settings. The authors of papers published in EJP/ECP retain the copyright. We ask for the permission to use the material in any form. We also require that the initial publication in EJP or ECP is acknowledged in any future publication of the same article. Before a paper is published in the Electronic Journal of Probability or Electronic Communications in Probability we must receive a hard-copy of the copyright form. Please mail it to Philippe Carmona Laboratoire Jean Leray UMR 6629 Universite de Nantes, 2, Rue de la Houssinière BP 92208 F-44322 Nantes Cédex 03 France You can also send it by FAX: (33|0) 2 51 12 59 12 to the attention of Philippe Carmona. The preferred way is to send a scanned (jpeg or pdf) copy of the signed copyright form to the managing editor Philippe Carmona at ejpecpme@math.univ-nantes.fr. If a paper has several authors, the corresponding author signs the copyright form on behalf of all the authors.

Original article at: http://www.math.washington.edu/~ejpecp/ECP/viewarticle.php?id=1685