Samuel Burer

A Slightly Lifted Convex Relaxation for Nonconvex Quadratic Programming with Ball Constraints

  • Samuel Burer
    • Categories Cone Programming, Global Optimization Theory, Quadratic Programming

    \(\) Globally optimizing a nonconvex quadratic over the intersection of \(m\) balls in \(\mathbb{R}^n\) is known to be polynomial-time solvable for fixed \(m\). Moreover, when \(m=1\), the standard semidefinite relaxation is exact, and when \(m=2\), it has recently been shown that an exact relaxation can be constructed via a disjunctive semidefinite formulation based on essentially two copies of the \(m=1\) case. … Read more

    A Strengthened SDP Relaxation for Quadratic Optimization Over the Stiefel Manifold

  • Samuel Burer
  • Kyungchan Park
    • Categories Global Optimization, Quadratic Programming, Semi-definite Programming Tags , ,

    We study semidefinite programming (SDP) relaxations for the NP-hard problem of globally optimizing a quadratic function over the Stiefel manifold. We introduce a strengthened relaxation based on two recent ideas in the literature: (i) a tailored SDP for objectives with a block-diagonal Hessian; (ii) and the use of the Kronecker matrix product to construct SDP relaxations. Using synthetic instances on … Read more

    Strengthened SDP Relaxation for an Extended Trust Region Subproblem with an Application to Optimal Power Flow

  • Samuel Burer
  • Anders Eltved
    • Categories Quadratic Programming, Semi-definite Programming Tags ,

    We study an extended trust region subproblem minimizing a nonconvex function over the hollow ball $r \le \|x\| \le R$ intersected with a full-dimensional second order cone (SOC) constraint of the form $\|x – c\| \le b^T x – a$. In particular, we present a class of valid cuts that improve existing semidefinite programming (SDP) … Read more

    Convex Hull Representations for Bounded Products of Variables

  • Kurt M. Anstreicher
  • Samuel Burer
  • Kyungchan Park
    • Categories Convex Optimization, Global Optimization Theory, Second-Order Cone Programming Tags , , ,

    It is well known that the convex hull of {(x,y,xy)}, where (x,y) is constrained to lie in a box, is given by the Reformulation-Linearization Technique (RLT) constraints. Belotti et al. (2010) and Miller et al. (2011) showed that if there are additional upper and/or lower bounds on the product z=xy, then the convex hull can … Read more

    Exact Semidefinite Formulations for a Class of (Random and Non-Random) Nonconvex Quadratic Programs

  • Samuel Burer
  • Yinyu Ye
    • Categories Global Optimization Theory, Quadratic Programming, Semi-definite Programming Tags , ,

    We study a class of quadratically constrained quadratic programs (QCQPs), called {\em diagonal QCQPs\/}, which contain no off-diagonal terms $x_j x_k$ for $j \ne k$, and we provide a sufficient condition on the problem data guaranteeing that the basic Shor semidefinite relaxation is exact. Our condition complements and refines those already present in the literature … Read more

    A Data-Driven Distributionally Robust Bound on the Expected Optimal Value of Uncertain Mixed 0-1 Linear Programming

  • Samuel Burer
  • Guanglin Xu
    • Categories Robust Optimization, Semi-definite Programming, Stochastic Programming

    This paper studies the expected optimal value of a mixed 0-1 programming problem with uncertain objective coefficients following a joint distribution. We assume that the true distribution is not known exactly, but a set of independent samples can be observed. Using the Wasserstein metric, we construct an ambiguity set centered at the empirical distribution from … Read more

    A Copositive Approach for Two-Stage Adjustable Robust Optimization with Uncertain Right-Hand Sides

  • Samuel Burer
  • Guanglin Xu
    • Categories Dynamic Programming, Linear, Cone and Semidefinite Programming, Robust Optimization Tags , , , , ,

    We study two-stage adjustable robust linear programming in which the right-hand sides are uncertain and belong to a convex, compact uncertainty set. This problem is NP-hard, and the affine policy is a popular, tractable approximation. We prove that under standard and simple conditions, the two-stage problem can be reformulated as a copositive optimization problem, which … Read more

    Quadratic Programs with Hollows

  • Kurt M. Anstreicher
  • Samuel Burer
  • Boshi Yang
    • Categories Linear, Cone and Semidefinite Programming, Semi-definite Programming Tags , ,

    Let $\F$ be a quadratically constrained, possibly nonconvex, bounded set, and let $\E_1, \ldots, \E_l$ denote ellipsoids contained in $\F$ with non-intersecting interiors. We prove that minimizing an arbitrary quadratic $q(\cdot)$ over $\G := \F \setminus \cup_{k=1}^\ell \myint(\E_k)$ is no more difficult than minimizing $q(\cdot)$ over $\F$ in the following sense: if a given semidefinite-programming … Read more

    Robust Sensitivity Analysis of the Optimal Value of Linear Programming

  • Samuel Burer
  • Guanglin Xu
    • Categories Quadratic Programming, Robust Optimization, Semi-definite Programming Tags , , , , ,

    We propose a framework for sensitivity analysis of linear programs (LPs) in minimiza- tion form, allowing for simultaneous perturbations in the objective coefficients and right-hand sides, where the perturbations are modeled in a compact, convex uncertainty set. This framework unifies and extends multiple approaches for LP sensitivity analysis in the literature and has close ties … Read more