Search Results - "LEWIS, Adrian S"
-
1
Nonsmooth optimization via quasi-Newton methods
Published in Mathematical programming (01-10-2013)“…We investigate the behavior of quasi-Newton algorithms applied to minimize a nonsmooth function f , not necessarily convex. We introduce an inexact line search…”
Get full text
Journal Article -
2
Alternating Projections on Manifolds
Published in Mathematics of operations research (01-02-2008)“…We prove that if two smooth manifolds intersect transversally, then the method of alternating projections converges locally at a linear rate. We bound the…”
Get full text
Journal Article -
3
Error Bounds, Quadratic Growth, and Linear Convergence of Proximal Methods
Published in Mathematics of operations research (01-08-2018)“…The proximal gradient algorithm for minimizing the sum of a smooth and nonsmooth convex function often converges linearly even without strong convexity. One…”
Get full text
Journal Article -
4
Stabilization via Nonsmooth, Nonconvex Optimization
Published in IEEE transactions on automatic control (01-11-2006)“…Nonsmooth variational analysis and related computational methods are powerful tools that can be effectively applied to identify local minimizers of nonconvex…”
Get full text
Journal Article -
5
Generic nondegeneracy in convex optimization
Published in Proceedings of the American Mathematical Society (01-07-2011)“…lower- \mathbf{C}^2 functions…”
Get full text
Journal Article -
6
Variational analysis of the Crouzeix ratio
Published in Mathematical programming (01-07-2017)“…Let W ( A ) denote the field of values (numerical range) of a matrix A . For any polynomial p and matrix A , define the Crouzeix ratio to have numerator max |…”
Get full text
Journal Article -
7
Clarke Subgradients for Directionally Lipschitzian Stratifiable Functions
Published in Mathematics of operations research (01-05-2015)“…Using a geometric argument, we show that under a reasonable continuity condition, the Clarke subdifferential of a semi-algebraic (or more generally…”
Get full text
Journal Article -
8
Generic Optimality Conditions for Semialgebraic Convex Programs
Published in Mathematics of operations research (01-02-2011)“…We consider linear optimization over a nonempty convex semialgebraic feasible region F . Semidefinite programming is an example. If F is compact, then for…”
Get full text
Journal Article -
9
Differentiability of cone-monotone functions on separable Banach space
Published in Proceedings of the American Mathematical Society (01-04-2004)“…Motivated by applications to (directionally) Lipschitz functions, we provide a general result on the almost everywhere Gâteaux differentiability of real-valued…”
Get full text
Journal Article -
10
Level set methods for finding critical points of mountain pass type
Published in Nonlinear analysis (01-08-2011)“…Computing mountain passes is a standard way of finding critical points. We describe a numerical method for finding critical points that is convergent in the…”
Get full text
Journal Article -
11
Dykstras algorithm with bregman projections: A convergence proof
Published in Optimization (01-01-2000)“…Dykstra's algorithm and the method of cyclic Bregman projections are often employed to solve best approximation and convex feasibility problems, which are…”
Get full text
Journal Article -
12
Variational analysis of functions of the roots of polynomials
Published in Mathematical programming (01-11-2005)“…The Gauss-Lucas Theorem on the roots of polynomials nicely simplifies the computation of the subderivative and regular subdifferential of the abscissa mapping…”
Get full text
Journal Article -
13
Randomized Methods for Linear Constraints: Convergence Rates and Conditioning
Published in Mathematics of operations research (01-08-2010)“…We study randomized variants of two classical algorithms: coordinate descent for systems of linear equations and iterated projections for systems of linear…”
Get full text
Journal Article -
14
Variational Analysis of the Abscissa Mapping for Polynomials via the Gauss-Lucas Theorem
Published in Journal of global optimization (01-04-2004)“…Consider the linear space [Weierstrass p]n of polynomials of degree n or less over the complex field. The abscissa mapping on [Weierstrass p]n is the mapping…”
Get full text
Journal Article -
15
Quadratic expansions of spectral functions
Published in Linear algebra and its applications (01-01-2002)“…A function, F, on the space of n×n real symmetric matrices is called spectral if it depends only on the eigenvalues of its argument, that is F(A)=F(UAUT) for…”
Get full text
Journal Article -
16
Self-concordant barriers for hyperbolic means
Published in Mathematical programming (01-10-2001)“…The geometric mean and the function (det(·))^sup 1/m^ (on the m-by-m positive definite matrices) are examples of "hyperbolic means": functions of the form…”
Get full text
Journal Article -
17
Lipschitz minimization and the Goldstein modulus
Published 21-05-2024“…Goldstein's 1977 idealized iteration for minimizing a Lipschitz objective fixes a distance - the step size - and relies on a certain approximate subgradient…”
Get full text
Journal Article -
18
The complexity of first-order optimization methods from a metric perspective
Published 04-05-2023“…A central tool for understanding first-order optimization algorithms is the Kurdyka-Lojasiewicz inequality. Standard approaches to such methods rely crucially…”
Get full text
Journal Article -
19
Local geometry of feasible regions via smooth paths
Published 13-08-2024“…Variational analysis presents a unified theory encompassing in particular both smoothness and convexity. In a Euclidean space, convex sets and smooth manifolds…”
Get full text
Journal Article -
20
Recognizing weighted means in geodesic spaces
Published 06-06-2024“…Geodesic metric spaces support a variety of averaging constructions for given finite sets. Computing such averages has generated extensive interest in diverse…”
Get full text
Journal Article