Journal: | Computational & applied mathematics |
Database: | PERIÓDICA |
System number: | 000310700 |
ISSN: | 0101-8205 |
Authors: | Santos, Reginaldo J1 Pierro, Alvaro R. de2 |
Institutions: | 1Universidade Federal de Minas Gerais, Departamento de Matematica, Belo Horizonte, Minas Gerais. Brasil 2Universidade Estadual de Campinas, Departamento de Matematica Aplicada, Campinas, Sao Paulo. Brasil |
Year: | 2006 |
Volumen: | 25 |
Number: | 1 |
Pages: | 111-128 |
Country: | Brasil |
Language: | Inglés |
Document type: | Artículo |
Approach: | Experimental, analítico |
English abstract | We study the effect of the nonlinear dependence of the iterate x k of Conjugate Gradients method (CG) from the data b in the GCV procedure to stop the iterations. We compare two versions of using GCV to stop CG. In one version we compute the GCV function with the iterate x k depending linearly from the data b and the other one depending nonlinearly. We have tested the two versions in a large scale problem: positron emission tomography (PET). Our results suggest the necessity of considering the nonlinearity for the GCV function to obtain a reasonable stopping criterion |
Disciplines: | Matemáticas |
Keyword: | Matemáticas puras, Validación cruzada, Tomografía, Gradiente conjugado |
Keyword: | Mathematics, Pure mathematics, Cross validation, Tomography, Conjugate gradient |
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