## Convergence rates for regularized solutions

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- by Mark A. Lukas PDF
- Math. Comp.
**51**(1988), 107-131 Request permission

## Abstract:

Given a first-kind integral equation \[ \mathcal {K}u(x) = \int _0^1 {K(x,t)u(t) dt = f(x)} \] with discrete noisy data ${d_i} = f({x_i}) + {\varepsilon _i}$, $i = 1,2, \ldots ,n$, let ${u_{n\alpha }}$ be the minimizer in a Hilbert space*W*of the regularization functional $(1/n)\sum {(\mathcal {K}} u({x_i}) - {d_i}{)^2} + \alpha \left \| u \right \|_W^2$. It is shown that in any one of a wide class of norms, which includes ${\left \| \cdot \right \|_W}$, if $\alpha \to 0$ in a certain way as $n \to \infty$, then ${u_{n\alpha }}$ converges to the true solution ${u_0}$. Convergence rates are obtained and are used to estimate the optimal regularization parameter $\alpha$.

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*Numer. Math.*(To appear.)

## Additional Information

- © Copyright 1988 American Mathematical Society
- Journal: Math. Comp.
**51**(1988), 107-131 - MSC: Primary 65R20; Secondary 41A25, 45L05
- DOI: https://doi.org/10.1090/S0025-5718-1988-0942146-8
- MathSciNet review: 942146