Abstract
We consider the NP-hard problem of minimizing a convex quadratic function over the integer lattice \({\mathbf{Z}}^n\). We present a simple semidefinite programming (SDP) relaxation for obtaining a nontrivial lower bound on the optimal value of the problem. By interpreting the solution to the SDP relaxation probabilistically, we obtain a randomized algorithm for finding good suboptimal solutions, and thus an upper bound on the optimal value. The effectiveness of the method is shown for numerical problem instances of various sizes.
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We thank three anonymous referees for providing helpful comments and constructive remarks.
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Park, J., Boyd, S. A semidefinite programming method for integer convex quadratic minimization. Optim Lett 12, 499–518 (2018). https://doi.org/10.1007/s11590-017-1132-y
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DOI: https://doi.org/10.1007/s11590-017-1132-y