Nosce hostem : searching with opponent models
Jeroen Donkers · 2003
During the time I was a programmer and system manager at the department of Medical Informatics, I saw many Ph.D. students doing their work.From a distance, such Ph.D. research seemed not that difficult, so I decided to follow this track.After re-entering and completing my academic studies, I was able to begin with my own Ph.D. research; first on the subject of my Master's thesis: reasoning with uncertainty.Later I switched to the subject of computer game-playing, which was a new challenging topic for me at that time.My motivation for the new topic was almost automatic since I like games and playing games, moreover, IKAT had many people who knew much of the subject and who could criticise me.Apparently, an issue which encouraged me to do even better.Submitted papers were accepted and it finally resulted in this thesis.Research on computers and board games is a joy for me since because, among other things, it is fundamental science, revealing the properties of complex structures that are hidden inside games.Owing to my relatively late start I was able to observe the subject at a somewhat more abstract level.This sometimes led to interesting discussions in the games group.The goal of my research was to investigate the properties of a promising search method, Opponent-Model search, that had been invented six years earlier.At the start, the majority of my research was more theoretical than practical.As time went on, however, I became involved in competitive computer game-playing and a small olympic flame was lit inside me.I am convinced that the theoretical and practical results obtained during this research will be of great value to future researchers.However, the main outcome of this research is to be summarized as: whatever the promises of Opponent-Model search, its applicability is clearly less than expected previously.The enormous efforts, big support and tough lessons by Jaap van den Herik, made it possible for me to complete the research successfully and to submit this thesis.Jos Uiterwijk kept me on the road and was never tired to correct the same typos in whatever draft version again and again.I wish to express my gratitude to IKAT and the Faculty of General Science for the opportunity to perform and fulfil this research task.I thank all my colleagues for their patience and co-operation and for taking the extra work that came on their shoulders.In particular I would like to thank Floris Wiesman, who introduced me to the wonders of L A T E X and who was always willing to answer those silly little questions on how to write a thesis.My fellow students taught me much about computer game-playing, so I thank Mark Winands, Levente Kocsis, and Erik van der Werf for their