CONVERGENCE
OF
OPTIMIZATION ALGORITHMS
The goal of this monograph is to present in a rigorous mathematical frame
the main aspects of convergence of the optimization algorithms. The convergence
of the Newton method for unconstrained optimization, the ellipsoid and the
general interior point methods for linear programming, as well as the barrier
and cutting plane methods for constrained optimization are considered.
The
monograph is structured în 8 chapters. The first one has an introductory
character giving some insights into standard optimization problems as well
as into the standard problems of numerical linear algebra. The next three
chapters present in a very general manner the fundamental concepts of global
and asimptotic convergence. The main part of the monograph is represented
by chapters 5, 6 and 7. Chapter 5 considers the convergence analysis of unconstrained
optimization algorithms. The descent gradient method and the Newton method
with backtracking are looked upon in details. A special section is dedicated
to the analysis of the Newton method for self-concordant functions. It is
shown that the number of iterations corresponding to the damped Newton algorithm
with backtracking linear searching depends on the initial suboptimality,
as well as on a number of (unknown) parameters associated with the function
and its Hessian. Chapter 6 is for convergence analysis of the simplex method,
the ellipsoid method and the path-following interior point methods for linear
programming. In chapter 7 the convergence analysis of the barrier method
and of the cutting plane method for constrained optimization are presented.
For the self-concordant, strong convex barrier functions it is shown that
the number of Newton iterations is a function of the number of inequalities,
of the parameter of linear searching with backtracking, as well as of some
other known constants. The last chapter includes some considerations on theory
versus empiricism in the analysis of optimization algorithms. The veritable
algorithmist always swings between pure theoretical developments and experimental
ones, being aware that neither of them is superior to each other, they only
complete each other and only their joined results can eventually lead to
the understanding of the efficiency and limits of algorithms.
The
book has been written to serve a diverse audience of scientists, engineers
and decision makers, researchers, computer scientists or professionals working
in academia, business, industry and government facing design optimization
models and algorithms.
Neculai Andrei