Abstract
In this paper we establish an estimate for the rate of convergence of the Krasnosel’skiĭ-Mann iteration for computing fixed points of non-expansive maps. Our main result settles the Baillon-Bruck conjecture [3] on the asymptotic regularity of this iteration. The proof proceeds by establishing a connection between these iterates and a stochastic process involving sums of non-homogeneous Bernoulli trials. We also exploit a new Hoeffdingtype inequality to majorize the expected value of a convex function of these sums using Poisson distributions.
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Supported by Fondecyt 1100046 and Núcleo Milenio Información y Coordinación en Redes ICM/FIC P10-024F.
Supported by Basal-Conicyt project and Núcleo Milenio Información y Coordinaci ón en Redes ICM/FIC P10-024F.
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Cominetti, R., Soto, J.A. & Vaisman, J. On the rate of convergence of Krasnosel’skiĭ-Mann iterations and their connection with sums of Bernoullis. Isr. J. Math. 199, 757–772 (2014). https://doi.org/10.1007/s11856-013-0045-4
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DOI: https://doi.org/10.1007/s11856-013-0045-4