{ "id": "1404.3184", "version": "v1", "published": "2014-04-11T18:50:34.000Z", "updated": "2014-04-11T18:50:34.000Z", "title": "Decreasing Weighted Sorted $\\ell_1$ Regularization", "authors": [ "Xiangrong Zeng", "Mário A. T. Figueiredo" ], "comment": "5 pages, 2 figures", "categories": [ "cs.CV", "cs.IT", "cs.LG", "math.IT" ], "abstract": "We consider a new family of regularizers, termed {\\it weighted sorted $\\ell_1$ norms} (WSL1), which generalizes the recently introduced {\\it octagonal shrinkage and clustering algorithm for regression} (OSCAR) and also contains the $\\ell_1$ and $\\ell_{\\infty}$ norms as particular instances. We focus on a special case of the WSL1, the {\\sl decreasing WSL1} (DWSL1), where the elements of the argument vector are sorted in non-increasing order and the weights are also non-increasing. In this paper, after showing that the DWSL1 is indeed a norm, we derive two key tools for its use as a regularizer: the dual norm and the Moreau proximity operator.", "revisions": [ { "version": "v1", "updated": "2014-04-11T18:50:34.000Z" } ], "analyses": { "keywords": [ "decreasing", "regularization", "moreau proximity operator", "argument vector", "special case" ], "note": { "typesetting": "TeX", "pages": 5, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1404.3184Z" } } }