AN INVESTIGATION OF ARTIFICIAL
IMMUNE SYSTEMS AND VARIABLE
SELECTION TECHNIQUES FOR
CREDIT SCORING
A thesis submitted in fulfilment of the requirements for
the degree of Doctor of Philosophy
Kevin Leung Kan Hing
B.Bus (Business Information Systems)(Honours)
B.Bus (Business Information Systems)
School of Business Information Technology
Business Portfolio
RMIT University
December 2008
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CANDIDATE’S CERTIFICATION
I certify that except where due acknowledgement has been made, the work is that of the author
alone; the work has not been submitted previously, in whole or in part, to qualify for any other
academic award; the content of the thesis is the result of work which has been carried out since
the official commencement date of the approved research program; and, any editorial work,
paid or unpaid, carried out by a third party is acknowledged.
Signed:
Name:
Date:
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ACKNOWLEDGEMENTS
A PhD thesis is a project that requires the assistance of many people. My completion of this
project would not have been possible without the guidance of my supervisors. First and fore-
most, I would like to express my deepest gratitude to my senior supervisor, Dr France Cheong,
for motivating me to undertake a PhD and for his invaluable guidance and support during the
period of my candidature. Dr France Cheong was a mentor to me and not only did he advise
and guide me through my lengthy journey, but he also trained me to have the necessary teaching
skills to be ready to enter the world of academia. I am also grateful to my second supervisor,
Dr Christopher Cheong, for his patience, friendship and moral support.
Sincere thanks go to RMIT University, especially to Professor Brian Corbitt, for the financial
support provided through the Australian Postgraduate Award, RMIT Business Portfolio Post-
graduate Research scholarship, and funding for publishing papers and attending conferences.
Professor Brian Corbitt ensured that I was provided with all the necessary resources that were
required. Without such support, I would not have been able to carry out this research.
I would also like to take this opportunity to thank my parents, Maurice and Roseline Leung, for
supporting my educational goals, encouraging and motivating me, and for their unconditional
love and prayers.
I need to thank all of the professors and staff members from my school for the nice working
environment. A special thank-you goes to Mr Patrick Poppins for his involvement in getting
me in touch with the corporate world. I also need to acknowledge other professors, Professor
Timothy Fry and Professor Richard Heaney, both from the School of Economics, Finance and
Marketing, for their useful support and advice.
In this project, I had the pleasure of working with interesting people from the corporate world.
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I would like to thank Mr Sean O’Farrell and Mr Robert Tissington for sharing their practical
experience and knowledge with me. The meetings and discussions we had on numerous occa-
sions were both interesting and fruitful.
I must not forget all of my research colleagues for helping me through this arduous journey.
Their precious advice, constant cheering and friendship are deeply valued by me. Special thanks
go to Hui Chung Liang, Marie-Anne Cam, Hasniza Mohd Taib, Ju-Ai Ng, and Joerg Paschke.
I am also grateful to Irwin Tse, Patrice Hung, Kenny How, Didier Ng, Jean-Yann Ng, Deanie
Tang, Sandra Liong, Binesh Seetanah, Patrice Hau, and Rakibul Hasan Syed for their encour-
agement and for believing in me.
Finally, I would like to thank my editor, Julia Farrell, and all the anonymous reviewers of
the various papers which have been produced as part of this research. Their useful comments
helped in improving the quality of this thesis. I am also grateful to all my other friends and
family members, and finally to God, who makes everything possible.
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DEDICATION
This work is dedicated to my grandmother, Popo Leung Kan Hing, who passed away in 2007
while I was doing my PhD, and to my parents, Maurice and Roseline Leung Kan Hing. Without
their patience, understanding, support, and above all love, the completion of this work would
not have been possible.