Scaled memoryless symmetric rank one method for large-scale unconstrained optimization

Memoryless quasi-Newton method is precisely the quasi-Newton method for which the initial approximation to the inverse of Hessian, at each step, is taken as the identity matrix. Hence the memoryless quasi-Newton direction can be computed without the storage of matrices, namely n2 storages. In this...

Full description

Bibliographic Details
Main Authors: Leong, Wah June, Abu Hassan, Malik
Format: Conference or Workshop Item
Published: 2008
_version_ 1825944483575889920
author Leong, Wah June
Abu Hassan, Malik
author_facet Leong, Wah June
Abu Hassan, Malik
author_sort Leong, Wah June
collection UPM
description Memoryless quasi-Newton method is precisely the quasi-Newton method for which the initial approximation to the inverse of Hessian, at each step, is taken as the identity matrix. Hence the memoryless quasi-Newton direction can be computed without the storage of matrices, namely n2 storages. In this paper, a scaled memoryless symmetric rank one (SR1) method for solving very large (with dimensions up to 106) unconstrained optimization problems is presented. The idea is to incorporate the SR1 update in the framework of the memoryless quasi-Newton method. However, it is well-known that the SR1 update may not preserve positive definiteness even when updated from a positive definite matrix. Therefore, instead of using the identity matrix within the memoryless SR1 method we use a positive multiple of the identity (hence our choice of terminology). The used scaling factor is derived in such a way to improve the condition and preserves the positive definiteness of the scaled memoryless SR1 update. Under very mild conditions it is shown that, for strictly convex objective functions, the method is globally and R−linearly convergent. Numerical results show that the scaled memoryless SR1 method is very encouraging.
first_indexed 2024-03-06T07:16:33Z
format Conference or Workshop Item
id upm.eprints-8889
institution Universiti Putra Malaysia
last_indexed 2024-03-06T07:16:33Z
publishDate 2008
record_format dspace
spelling upm.eprints-88892015-01-21T08:27:20Z http://psasir.upm.edu.my/id/eprint/8889/ Scaled memoryless symmetric rank one method for large-scale unconstrained optimization Leong, Wah June Abu Hassan, Malik Memoryless quasi-Newton method is precisely the quasi-Newton method for which the initial approximation to the inverse of Hessian, at each step, is taken as the identity matrix. Hence the memoryless quasi-Newton direction can be computed without the storage of matrices, namely n2 storages. In this paper, a scaled memoryless symmetric rank one (SR1) method for solving very large (with dimensions up to 106) unconstrained optimization problems is presented. The idea is to incorporate the SR1 update in the framework of the memoryless quasi-Newton method. However, it is well-known that the SR1 update may not preserve positive definiteness even when updated from a positive definite matrix. Therefore, instead of using the identity matrix within the memoryless SR1 method we use a positive multiple of the identity (hence our choice of terminology). The used scaling factor is derived in such a way to improve the condition and preserves the positive definiteness of the scaled memoryless SR1 update. Under very mild conditions it is shown that, for strictly convex objective functions, the method is globally and R−linearly convergent. Numerical results show that the scaled memoryless SR1 method is very encouraging. 2008-08-27 Conference or Workshop Item PeerReviewed Leong, Wah June and Abu Hassan, Malik (2008) Scaled memoryless symmetric rank one method for large-scale unconstrained optimization. In: 4th Sino-Japanese Optimization Meeting (SJOM 2008), 27-31 Aug. 2008, Tainan, Taiwan. (pp. 1-10).
spellingShingle Leong, Wah June
Abu Hassan, Malik
Scaled memoryless symmetric rank one method for large-scale unconstrained optimization
title Scaled memoryless symmetric rank one method for large-scale unconstrained optimization
title_full Scaled memoryless symmetric rank one method for large-scale unconstrained optimization
title_fullStr Scaled memoryless symmetric rank one method for large-scale unconstrained optimization
title_full_unstemmed Scaled memoryless symmetric rank one method for large-scale unconstrained optimization
title_short Scaled memoryless symmetric rank one method for large-scale unconstrained optimization
title_sort scaled memoryless symmetric rank one method for large scale unconstrained optimization
work_keys_str_mv AT leongwahjune scaledmemorylesssymmetricrankonemethodforlargescaleunconstrainedoptimization
AT abuhassanmalik scaledmemorylesssymmetricrankonemethodforlargescaleunconstrainedoptimization