Month: March 2018

Improving the Flexibility and Robustness of Model-Based Derivative-Free Optimization Solvers

  • Coralia Cartis
  • Jan Fiala
  • Benjamin Marteau
  • Lindon Roberts
    • Categories Nonlinear Optimization Tags , , , , ,

    We present DFO-LS, a software package for derivative-free optimization (DFO) for nonlinear Least-Squares (LS) problems, with optional bound constraints. Inspired by the Gauss-Newton method, DFO-LS constructs simplified linear regression models for the residuals. DFO-LS allows flexible initialization for expensive problems, whereby it can begin making progress from as few as two objective evaluations. Numerical results … Read more

    A barrier-type method for multiobjective optimization

  • Ellen H. Fukuda
  • L. M. Graña Drummond
  • Fernanda M. P. Raupp
    • Categories Multi-Criteria Optimization Tags , , ,

    For solving constrained multicriteria problems, we introduce the multiobjective barrier method (MBM), which extends the scalar-valued internal penalty method. This multiobjective version of the classical method also requires a penalty barrier for the feasible set and a sequence of nonnegative penalty parameters. Differently from the single-valued procedure, MBM is implemented by means of an auxiliary … Read more

    Derivative-Free Superiorization With Component-Wise Perturbations

  • Yair Censor
  • Howard Heaton
  • Reinhard W. Schulte
    • Categories Biomedical Applications, Constrained Nonlinear Optimization, Nonsmooth Optimization Tags , , , , ,

    Superiorization reduces, not necessarily minimizes, the value of a target function while seeking constraints-compatibility. This is done by taking a solely feasibility-seeking algorithm, analyzing its perturbations resilience, and proactively perturbing its iterates accordingly to steer them toward a feasible point with reduced value of the target function. When the perturbation steps are computationally efficient, this … Read more

    Entropic proximal operators for nonnegative trigonometric polynomials

  • Hsiao-Han Chao
  • Lieven Vandenberghe
    • Categories Convex and Nonsmooth Optimization, Linear, Cone and Semidefinite Programming

    Signal processing applications of semidefinite optimization are often rooted in sum-of-squares representations of nonnegative trigonometric polynomials. Interior-point solvers for semidefinite optimization can handle constraints of this form with a per-iteration-complexity that is cubic in the degree of the trigonometric polynomial. The purpose of this paper is to discuss first-order methods with a lower complexity per … Read more

    Stochastic model-based minimization of weakly convex functions

  • Damek Davis
  • Dmitriy Drusvyatskiy
    • Categories Convex and Nonsmooth Optimization Tags , , , , ,

    We consider an algorithm that successively samples and minimizes stochastic models of the objective function. We show that under weak-convexity and Lipschitz conditions, the algorithm drives the expected norm of the gradient of the Moreau envelope to zero at the rate $O(k^{-1/4})$. Our result yields the first complexity guarantees for the stochastic proximal point algorithm … Read more

    Derivative-Free Optimization of Noisy Functions via Quasi-Newton Methods

  • Albert S. Berahas
  • Richard H. Byrd
  • Jorge Nocedal
    • Categories Nonlinear Optimization, Unconstrained Optimization Tags , ,

    This paper presents a finite difference quasi-Newton method for the minimization of noisy functions. The method takes advantage of the scalability and power of BFGS updating, and employs an adaptive procedure for choosing the differencing interval h based on the noise estimation techniques of Hamming (2012) and Moré and Wild (2011). This noise estimation procedure … Read more

    New SOCP relaxation and branching rule for bipartite bilinear programs

  • Santanu S. Dey
  • Asteroide Santana
  • Yang Wang
    • Categories Global Optimization Applications, Global Optimization Theory

    A bipartite bilinear program (BBP) is a quadratically constrained quadratic optimization problem where the variables can be partitioned into two sets such that fixing the variables in any one of the sets results in a linear program. We propose a new second order cone representable (SOCP) relaxation for BBP, which we show is stronger than … Read more

    A Dynamic Penalty Parameter Updating Strategy for Matrix-Free Sequential Quadratic Optimization

  • James V. Burke
  • Frank E. Curtis
  • Jiashan Wang
  • Hao Wang
    • Categories Constrained Nonlinear Optimization, Nonlinear Optimization Tags , , , , ,

    This paper focuses on the design of sequential quadratic optimization (commonly known as SQP) methods for solving large-scale nonlinear optimization problems. The most computationally demanding aspect of such an approach is the computation of the search direction during each iteration, for which we consider the use of matrix-free methods. In particular, we develop a method … Read more

    On the Consistent Path Problem

  • David Bergman
  • Leonardo Lozano
  • Cole Smith
    • Categories 0-1 Programming, Combinatorial Optimization, Cutting Plane Approaches

    The application of decision diagrams in combinatorial optimization has proliferated in the last decade. In recent years, authors have begun to investigate how to utilize not one, but a set of diagrams, to model constraints and objective function terms. Optimizing over a collection of decision diagrams, the problem we refer to as the consistent path … Read more

    Hadamard Directional Diff erentiability of the Optimal Value of a Linear Second-order Conic Programming Problem

  • Duan Qingsong
  • Liwei Zhang
  • Sainan Zhang
    • Categories Second-Order Cone Programming, Stochastic Programming Tags , , ,

    In this paper, we consider perturbation properties of a linear second-order conic optimization problem and its Lagrange dual in which all parameters in the problem are perturbed. We prove the upper semi-continuity of solution mappings for the primal problem and the Lagrange dual problem. We demonstrate that the optimal value function can be expressed as … Read more