Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Assessing the influence of observations on the generalization performance of the kernel Fisher discriminant classifier

Thesis (PhD (Statistics and Actuarial Science))—Stellenbosch University, 2008.

Saved in:
Bibliographic Details
Main Author: Lamont, Morné Michael Connell
Other Authors: Louw, Nelmarie
Format: Thesis
Language:English
Published: Stellenbosch : Stellenbosch University 2008
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613998726250496
access_status_str Open Access
author Lamont, Morné Michael Connell
author2 Louw, Nelmarie
author_browse Lamont, Morné Michael Connell
Louw, Nelmarie
author_facet Louw, Nelmarie
Lamont, Morné Michael Connell
author_sort Lamont, Morné Michael Connell
collection Thesis
dc_rights_str_mv Stellenbosch : Stellenbosch University
description Thesis (PhD (Statistics and Actuarial Science))—Stellenbosch University, 2008.
format Thesis
id oai:scholar.sun.ac.za:10019.1/1498
institution Stellenbosch University (South Africa)
language English
last_indexed 2026-06-10T12:45:01.662Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository
publishDate 2008
publishDateRange 2008
publishDateSort 2008
publisher Stellenbosch : Stellenbosch University
publisherStr Stellenbosch : Stellenbosch University
record_format dspace
source_str SUNScholar — Stellenbosch University Repository
spelling oai:scholar.sun.ac.za:10019.1/1498 Assessing the influence of observations on the generalization performance of the kernel Fisher discriminant classifier Lamont, Morné Michael Connell Louw, Nelmarie Steel, Sarel Stellenbosch University. Faculty of Economic and Management Sciences. Dept. of Statistics and Actuarial Science. Kernel Fisher discriminant analysis Atypical cases Kernel function Smallest enclosing hypersphere Thesis (PhD (Statistics and Actuarial Science))—Stellenbosch University, 2008. Kernel Fisher discriminant analysis (KFDA) is a kernel-based technique that can be used to classify observations of unknown origin into predefined groups. Basically, KFDA can be viewed as a non-linear extension of Fisher’s linear discriminant analysis (FLDA). In this thesis we give a detailed explanation how FLDA is generalized to obtain KFDA. We also discuss two methods that are related to KFDA. Our focus is on binary classification. The influence of atypical cases in discriminant analysis has been investigated by many researchers. In this thesis we investigate the influence of atypical cases on certain aspects of KFDA. One important aspect of interest is the generalization performance of the KFD classifier. Several other aspects are also investigated with the aim of developing criteria that can be used to identify cases that are detrimental to the KFD generalization performance. The investigation is done via a Monte Carlo simulation study. The output of KFDA can also be used to obtain the posterior probabilities of belonging to the two classes. In this thesis we discuss two approaches to estimate posterior probabilities in KFDA. Two new KFD classifiers are also derived which use these probabilities to classify observations, and their performance is compared to that of the original KFD classifier. The main objective of this thesis is to develop criteria which can be used to identify cases that are detrimental to the KFD generalization performance. Nine such criteria are proposed and their merit investigated in a Monte Carlo simulation study as well as on real-world data sets. Evaluating the criteria on a leave-one-out basis poses a computational challenge, especially for large data sets. In this thesis we also propose using the smallest enclosing hypersphere as a filter, to reduce the amount of computations. The effectiveness of the filter is tested in a Monte Carlo simulation study as well as on real-world data sets. Doctoral 2008-10-27T12:14:56Z 2010-06-01T08:23:07Z 2008-10-27T12:14:56Z 2010-06-01T08:23:07Z 2008-12 Thesis http://hdl.handle.net/10019.1/1498 en Stellenbosch : Stellenbosch University application/pdf Stellenbosch : Stellenbosch University
spellingShingle Kernel Fisher discriminant analysis
Atypical cases
Kernel function
Smallest enclosing hypersphere
Lamont, Morné Michael Connell
Assessing the influence of observations on the generalization performance of the kernel Fisher discriminant classifier
title Assessing the influence of observations on the generalization performance of the kernel Fisher discriminant classifier
title_full Assessing the influence of observations on the generalization performance of the kernel Fisher discriminant classifier
title_fullStr Assessing the influence of observations on the generalization performance of the kernel Fisher discriminant classifier
title_full_unstemmed Assessing the influence of observations on the generalization performance of the kernel Fisher discriminant classifier
title_short Assessing the influence of observations on the generalization performance of the kernel Fisher discriminant classifier
title_sort assessing the influence of observations on the generalization performance of the kernel fisher discriminant classifier
topic Kernel Fisher discriminant analysis
Atypical cases
Kernel function
Smallest enclosing hypersphere
url http://hdl.handle.net/10019.1/1498
work_keys_str_mv AT lamontmornemichaelconnell assessingtheinfluenceofobservationsonthegeneralizationperformanceofthekernelfisherdiscriminantclassifier