Title
Why a Pure Primal Newton Barrier Step May be Infeasible.
Abstract
Modern barrier methods for constrained optimization are sometimes portrayed conceptually as a sequence of inexact minimizations, with only a very few Newton iterations (perhaps just one) for each value of the barrier parameter. Unfortunately, this rosy image does not accurately reflect reality when the barrier parameter is reduced at a reasonable rate, as in a practical (long-step) method. Local analysis is presented indicating why a pure Newton step in a typical long-step barrier method for nonlinearly constrained optimization may be seriously infeasible, even when taken from an apparently favorable point; hence accurate calculation of the Newton direction does not guarantee an effective algorithm. The features described are illustrated numerically and connected to known theoretical results for well-behaved convex problems satisfying common assumptions such as self-concordancy. The contrasting nature of an approximate step to the desired minimizer of the barrier function is also discussed.
Year
DOI
Venue
1995
10.1137/0805001
SIAM JOURNAL ON OPTIMIZATION
Keywords
Field
DocType
INTERIOR METHOD,LOGARITHMIC BARRIER FUNCTION,PRIMAL METHOD,PRIMAL NEWTON STEP
Newton fractal,Mathematical optimization,Regular polygon,Barrier function,Barrier method,Newton's method in optimization,Local analysis,Mathematics,Constrained optimization
Journal
Volume
Issue
ISSN
5
1
1052-6234
Citations 
PageRank 
References 
15
8.21
5
Authors
1
Name
Order
Citations
PageRank
Margaret H. Wright11233182.31