{ "id": "1809.08571", "version": "v1", "published": "2018-09-23T10:13:17.000Z", "updated": "2018-09-23T10:13:17.000Z", "title": "Periodic Splines and Gaussian Processes for the Resolution of Linear Inverse Problems", "authors": [ "Anaïs Badoual", "Julien Fageot", "Michael Unser" ], "categories": [ "math.OC" ], "abstract": "This paper deals with the resolution of inverse problems in a periodic setting or, in other terms, the reconstruction of periodic continuous-domain signals from their noisy measurements. We focus on two reconstruction paradigms: variational and statistical. In the variational approach, the reconstructed signal is solution to an optimization problem that establishes a tradeoff between fidelity to the data and smoothness conditions via a quadratic regularization associated to a linear operator. In the statistical approach, the signal is modeled as a stationary random process defined from a Gaussian white noise and a whitening operator; one then looks for the optimal estimator in the mean-square sense. We give a generic form of the reconstructed signals for both approaches, allowing for a rigorous comparison of the two.We fully characterize the conditions under which the two formulations yield the same solution, which is a periodic spline in the case of sampling measurements. We also show that this equivalence between the two approaches remains valid on simulations for a broad class of problems. This extends the practical range of applicability of the variational method.", "revisions": [ { "version": "v1", "updated": "2018-09-23T10:13:17.000Z" } ], "analyses": { "subjects": [ "65K10", "62D05", "46E22", "41A15" ], "keywords": [ "linear inverse problems", "periodic spline", "gaussian processes", "resolution", "stationary random process" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }