BIT Numerical Mathematics

, Volume 36, Issue 2, pp 287–301 | Cite as

Limitations of the L-curve method in ill-posed problems

  • Martin Hanke


This paper considers the Tikhonov regularization method with the regularization parameter chosen by the so-called L-curve criterion. An infinite dimensional example is constructed for which the selected regularization parameter vanishes too rapidly as the noise to signal ratio in the data goes to zero. As a consequence the computed reconstructions do not converge to the true solution. Numerical examples are given to show that similar phenomena can be observed under more general assumptions in “discrete ill-posed problems” provided the exact solution of the problem is “smooth”.

Key words

Tikhonov regularization regularization parameter L-curve method 


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Copyright information

© BIT Foundation 1996

Authors and Affiliations

  • Martin Hanke
    • 1
  1. 1.Institut für Praktische MathematikUniversität KarlsruheKarlsruheGermany

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