eprintid: 2225 rev_number: 7 eprint_status: archive userid: 6 dir: disk0/00/00/22/25 datestamp: 2014-07-01 11:02:11 lastmod: 2014-07-01 11:02:11 status_changed: 2014-07-01 11:02:11 type: monograph metadata_visibility: show creators_name: Patrinos, Panagiotis creators_name: Stella, Lorenzo creators_name: Bemporad, Alberto creators_id: panagiotis.patrinos@imtlucca.it creators_id: lorenzo.stella@imtlucca.it creators_id: alberto.bemporad@imtlucca.it title: Forward-backward truncated Newton methods for convex composite optimization ispublished: unpub subjects: QA75 divisions: CSA full_text_status: none monograph_type: working_paper note: A preliminary version of this paper [1] was presented at the 52nd IEEE Conference on Decision and Control, Florence, Italy, December 11, 2013. abstract: This paper proposes two proximal Newton-CG methods for convex nonsmooth optimization problems in composite form. The algorithms are based on a a reformulation of the original nonsmooth problem as the unconstrained minimization of a continuously differentiable function, namely the forward-backward envelope (FBE). The first algorithm is based on a standard line search strategy, whereas the second one combines the global efficiency estimates of the corresponding first-order methods, while achieving fast asymptotic convergence rates. Furthermore, they are computationally attractive since each Newton iteration requires the approximate solution of a linear system of usually small dimension. date: 2014 date_type: published number: publisher: ArXiv pages: 39 institution: IMT Institute for Advanced Studies Lucca official_url: http://arxiv.org/abs/1402.6655 citation: Patrinos, Panagiotis and Stella, Lorenzo and Bemporad, Alberto Forward-backward truncated Newton methods for convex composite optimization. Working Paper # /2014 ArXiv (Unpublished)