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Related papers: On modified Halpern and Tikhonov-Mann iterations

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In this paper we use proof mining methods to compute rates of ($T$-)asymptotic regularity of the generalized Krasnoselskii-Mann-type iteration associated to a nonexpansive mapping $T:X\to X$ in a uniformly convex normed space $X$. For…

Optimization and Control · Mathematics 2025-01-23 Paulo Firmino , Laurentiu Leustean

In this paper we obtain a quadratic bound on the rate of asymptotic regularity for the Krasnoselski-Mann iterations of nonexpansive mappings in CAT(0)-spaces, whereas previous results guarantee only exponential bounds. The method we use is…

Functional Analysis · Mathematics 2007-05-23 Laurentiu Leustean

In this note we apply a lemma due to Sabach and Shtern to compute linear rates of asymptotic regularity for Halpern-type nonlinear iterations studied in optimization and nonlinear analysis.

Optimization and Control · Mathematics 2024-05-01 Horaţiu Cheval , Laurenţiu Leuştean

Functional autoregressive (FAR) models provide a fundamental framework for analyzing temporally dependent functional data. However, the infinite-dimensional nature of the underlying Hilbert space introduces intrinsic ill-posedness, as the…

Methodology · Statistics 2025-11-17 Ying Niu , Yuwei Zhao , Zhao Chen , Christina Dan Wang

In this paper we apply methods of proof mining to obtain a uniform effective rate of asymptotic regularity for the Mann iteration associated to $\kappa$-strict pseudo-contractions on convex subsets of Hilbert spaces.

Functional Analysis · Mathematics 2014-11-27 Daniel Ivan , Laurentiu Leustean

We apply proof mining methods to analyse a result of Boikanyo and Moro\c{s}anu on the strong convergence of a Halpern-type proximal point algorithm. As a consequence, we obtain quantitative versions of this result, providing uniform…

Optimization and Control · Mathematics 2021-03-01 Laurentiu Leustean , Pedro Pinto

In a Hilbert framework, we consider an inertial Tikhonov regularized dynamical system governed by a maximally comonotone operator, where the damping coefficient is proportional to the square root of the Tikhonov regularization parameter.…

Optimization and Control · Mathematics 2024-12-02 Zeng-Zhen Tan , Rong HU , Ya-Ping Fang

These lecture notes for a graduate class present the regularization theory for linear and nonlinear ill-posed operator equations in Hilbert spaces. Covered are the general framework of regularization methods and their analysis via spectral…

Functional Analysis · Mathematics 2021-02-09 Christian Clason

Fractional Tikhonov regularization methods have been recently proposed to reduce the oversmoothing property of the Tikhonov regularization in standard form, in order to preserve the details of the approximated solution. Their regularization…

Numerical Analysis · Mathematics 2020-09-07 Davide Bianchi , Alessandro Buccini , Marco Donatelli , Stefano Serra-Capizzano

We establish sharp estimates for the convergence rate of the Kranosel'ski\v{\i}-Mann fixed point iteration in general normed spaces, and we use them to show that the asymptotic regularity bound recently proved in [11] (Israel Journal of…

Optimization and Control · Mathematics 2017-01-31 Mario Bravo , Roberto Cominetti

We develop a generalized hybrid iterative approach for computing solutions to large-scale Bayesian inverse problems. We consider a hybrid algorithm based on the generalized Golub-Kahan bidiagonalization for computing Tikhonov regularized…

Numerical Analysis · Mathematics 2021-11-25 Julianne Chung , Arvind K. Saibaba

We prove a general quantitative theorem on the asymptotic behavior of stochastic quasi-Fej\'er monotone sequences in a broad metric context. Concretely, our result explicitly constructs a rate of convergence for such process, both in mean…

Optimization and Control · Mathematics 2026-05-08 Nicholas Pischke , Thomas Powell

This paper provides an effective uniform rate of metastability (in the sense of Tao) on the strong convergence of Halpern iterations of nonexpansive mappings in CAT(0) spaces. The extraction of this rate from an ineffective proof due to…

Functional Analysis · Mathematics 2012-06-11 Ulrich Kohlenbach , Laurentiu Leustean

We further study averaged and firmly nonexpansive mappings in the setting of geodesic spaces with a main focus on the asymptotic behavior of their Picard iterates. We use methods of proof mining to obtain an explicit quantitative version of…

Functional Analysis · Mathematics 2013-10-03 Adriana Nicolae

Inexact Newton regularization methods have been proposed by Hanke and Rieder for solving nonlinear ill-posed inverse problems. Every such a method consists of two components: an outer Newton iteration and an inner scheme providing…

Numerical Analysis · Mathematics 2011-11-09 Qinian Jin

In the framework of real Hilbert spaces, we investigate first-order dynamical systems governed by monotone and continuous operators. We demonstrate that when the monotone operator flow is augmented with a Tikhonov regularization term, the…

Optimization and Control · Mathematics 2025-04-29 Radu Ioan Bot , Dang-Khoa Nguyen

We investigate the asymptotic distributions of coordinates of regression M-estimates in the moderate $p/n$ regime, where the number of covariates $p$ grows proportionally with the sample size $n$. Under appropriate regularity conditions, we…

Statistics Theory · Mathematics 2016-12-20 Lihua Lei , Peter J. Bickel , Noureddine El Karoui

Let M be a compact Kaehler manifold equipped with a Hamiltonian action of a compact Lie group G. In [Invent. Math. 67 (1982), no.~3, 515--538], Guillemin and Sternberg showed that there is a geometrically natural isomorphism between the…

Symplectic Geometry · Mathematics 2012-10-19 William D. Kirwin

We investigate the asymptotic properties of the trajectories generated by a second-order dynamical system with Hessian driven damping and a Tikhonov regularization term in connection with the minimization of a smooth convex function in…

Optimization and Control · Mathematics 2020-08-03 Radu Ioan Bot , Ernö Robert Csetnek , Szilárd Csaba László

In the recent paper `Well-posedness and regularity for a generalized fractional Cahn-Hilliard system' (Atti Accad. Naz. Lincei Rend. Lincei Mat. Appl. 30 (2019), 437-478 -- see also arXiv:1804.11290), the same authors have studied viscous…

Analysis of PDEs · Mathematics 2020-07-10 Pierluigi Colli , Gianni Gilardi , Jürgen Sprekels