Title
Some Convergence Results for Howard's Algorithm
Abstract
This paper deals with convergence results of Howard's algorithm for the resolution of $\min_{a\in\mathcal{A}} (B^a x - c^a) = 0$, where $B^a$ is a matrix, $c^a$ is a vector, and $\mathcal{A}$ is a compact set. We show a global superlinear convergence result, under a monotonicity assumption on the matrices $B^a$. Extensions of Howard's algorithm for a max-min problem of the form $\max_{b\in\mathcal{B}} \min_{a\in\mathcal{A}} (B^{a,b}x - c^{a,b}) = 0$ are also proposed. In the particular case of an obstacle problem of the form $\min (Ax - b,$ $x - g) = 0$, where $A$ is an $N \times N$ matrix satisfying a monotonicity assumption, we show the convergence of Howard's algorithm in no more than $N$ iterations, instead of the usual $2^N$ bound. Still in the case of an obstacle problem, we establish the equivalence between Howard's algorithm and a primal-dual active set algorithm [M. Hintermüller, K. Ito, and K. Kunisch, SIAM J. Optim., 13 (2002), pp. 865-888]. The algorithms are illustrated on the discretization of nonlinear PDEs arising in the context of mathematical finance (American option and Merton's portfolio problem), of front propagation problems, and for the double-obstacle problem.
Year
DOI
Venue
2009
10.1137/08073041X
SIAM J. Numerical Analysis
Keywords
Field
DocType
semi- smooth newton's method,obstacle problem,primal-dual active set algorithm,howard's algorithm policy iterations,double-obstacle problem,convergence results,k. ito,global superlinear convergence result,portfolio problem,superlinear convergence,front propagation problem,convergence result,min-max problem.,monotonicity assumption,max-min problem,mathematical finance,satisfiability
Convergence (routing),Monotonic function,Discretization,Mathematical optimization,Active set method,Mathematical analysis,Matrix (mathematics),Algorithm,Compact space,Obstacle problem,Mathematics,Newton's method
Journal
Volume
Issue
ISSN
47
4
0036-1429
Citations 
PageRank 
References 
22
1.53
7
Authors
3
Name
Order
Citations
PageRank
Olivier Bokanowski19812.07
Stefania Maroso2252.18
Hasnaa Zidani310117.27