Abstract
The L-curve is a popular aid for determining a suitable value of the regularization parameter when solving linear discrete ill-posed problems by Tikhonov regularization. However, the computational effort required to determine the L-curve and its curvature can be prohibitive for large-scale problems. Recently, inexpensively computable approximations of the L-curve and its curvature, referred to as the L-ribbon and the curvature-ribbon, respectively, were proposed for the case when the regularization operator is the identity matrix. This note discusses the computation and performance of the L- and curvature-ribbons when the regularization operator is an invertible matrix.
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Calvetti, D., Reichel, L. & Shuibi, A. L-Curve and Curvature Bounds for Tikhonov Regularization. Numerical Algorithms 35, 301–314 (2004). https://doi.org/10.1023/B:NUMA.0000021764.16526.47
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DOI: https://doi.org/10.1023/B:NUMA.0000021764.16526.47