Conclusion
Transformation (6) smoothing thef(x) level lines explains the effectiveness ofr(α)-algorithms from visual geometrical considerations. It may be regarded as a satisfactory interpretation of space dilation in the direction of the difference of two successive subgradients. On the other hand, it preserves the gradient flavor of the method, in contrast to the classical ellipsoid method [11, 12], which is a successful interpretation of the subgradient method with space dilation in the direction of the subgradient. A sensible combination of ellipsoids of a special kind [5] with the ellipsoids ell(x0,a, b, c) is quite capable of producing, on the basis of a one-dimensional space dilation operator, effective algorithms that solve a broader class of problems than convex programming problems, e.g., the problem to find saddle points of convex-concave functions, particular cases of the problem of solving variational inequalities, and also special classes of linear and nonlinear complementarity problems.
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Translated from Kibernetika i Sistemnyi Analiz, No. 1, pp. 113–134, January–February, 1996.
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Stetsyuk, P.I. r-Algorithms and ellipsoids. Cybern Syst Anal 32, 93–110 (1996). https://doi.org/10.1007/BF02366587
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DOI: https://doi.org/10.1007/BF02366587