A Direct Splitting Method for Nonsmooth Variational Inequalities



We propose a direct splitting method for solving a nonsmooth variational inequality in Hilbert spaces. The weak convergence is established when the operator is the sum of two point-to-set and monotone operators. The proposed method is a natural extension of the incremental subgradient method for nondifferentiable optimization, which strongly explores the structure of the operator using projected subgradient-like techniques. The advantage of our method is that any nontrivial subproblem must be solved, like the evaluation of the resolvent operator. The necessity to compute proximal iterations is the main difficulty of other schemes for solving this kind of problem.


Maximal monotone operators Monotone variational inequalities Projection methods Splitting methods 



The authors would like to thank CNPq. Research for this paper was partially supported by PRONEX, PROCAD-nf—UFG/UnB/IMPA and by project CAPES-MES-CUBA 226/2012 “Modelos de Otimização e Aplicações”. The second author was supported by a scholarship for his doctoral studies, granted by CAPES. The authors would like to extend gratitude toward the anonymous referees whose suggestions helped us to improve the presentation of this paper.


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© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.IME, Federal University of Goiás, Campus Samambaia, CEP 74001-970GoiâniaBrazil
  2. 2.Federal Institute of Education, Science and TechnologyGoiâniaBrazil

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