University of Alberta by Darse Billings a Thesis Submitted to the Faculty Of

Total Page:16

File Type:pdf, Size:1020Kb

University of Alberta by Darse Billings a Thesis Submitted to the Faculty Of University of Alberta ALGORITHMS AND ASSESSMENT IN COMPUTER POKER by Darse Billings A thesis submitted to the Faculty of Graduate Studies and Research in partial ful- fillment of the requirements for the degree of Doctor of Philosophy. Department of Computing Science Edmonton, Alberta Fall 2006 University of Alberta Library Release Form Name of Author: Darse Billings Title of Thesis: Algorithms and Assessment in Computer Poker Degree: Doctor of Philosophy Year this Degree Granted: 2006 Permission is hereby granted to the University of Alberta Library to reproduce sin- gle copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. The author reserves all other publication and other rights in association with the copyright in the thesis, and except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatever without the author's prior written permission. Darse Billings Date: University of Alberta ALGORITHMS AND ASSESSMENT IN COMPUTER POKER by Darse Billings A thesis submitted to the Faculty of Graduate Studies and Research in partial ful- fillment of the requirements for the degree of Doctor of Philosophy. Department of Computing Science Edmonton, Alberta Fall 2006 University of Alberta Faculty of Graduate Studies and Research The undersigned certify that they have read, and recommend to the Faculty of Graduate Studies and Research for acceptance, a thesis entitled Algorithms and Assessment in Computer Poker submitted by Darse Billings in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Dr. Jonathan Schaeffer Co-Supervisor Dr. Duane Szafron Co-Supervisor Dr. Robert Holte Dr. Michael Carbonaro Dr. Michael Littman External Examiner Date: Dedication: To Howard and Eileen Billings, for their eternal love and support. And to Xor, for many years of unconditional love and friendship. Abstract The game of poker offers a clean well-defined domain in which to investigate some truly fundamental issues in computing science, such as how to handle deliberate misinformation, and how to make intelligent guesses based on partial knowledge. In the taxonomy of games, poker lies at the opposite end of the spectrum from well-studied board games like checkers and chess. Poker is a multi-player game with stochasticity (random events occurring over a known probability distribution), imperfect information (some information is hidden from each player), and partially observable outcomes (some information might never be known). Consequently, the use of deception, opponent modeling, and coping with uncertainty are indis- pensable elements of high-level strategic play. Traditional methods for computer game-playing are incapable of handling these properties. Writing a program to play a skillful game of poker is a challenging proposition from an engineering perspective as well, since each decision must be made quickly (typically about one second). A major theme of this dissertation is the evolution of architectures for poker-playing programs that has occurred since the research be- gan in 1992. Four distinct approaches we address are: knowledge-based systems, simulation, game-theoretic methods, and adaptive imperfect information game-tree search. Each phase of the research explored the strengths and weaknesses of the corresponding architectures, both in theory and in practice. The important problem of obtaining an accurate assessment of performance is also addressed. The creation of a powerful tool for this purpose, called DIVAT, is discussed in detail. The aca- demic papers arising from each of these studies constitute the core chapters of this thesis. The conclusion discusses some of the advantages and shortcomings of each approach, along with the most valuable lessons learned in the process. Although the goal of surpassing all human players has not yet been attained, the path has been cleared. The best poker programs are beginning to pose a serious threat, even in this most “human” of games. As programs continue to improve, they provide new insights into poker strategy, and valuable lessons on how to handle various forms of uncertainty. Preface It is very common for Ph.D. students to be dissatisfied with their dissertation. The feeling is especially acute in my case, because it could reflect poorly on the excellent work of my colleagues. Due to the scope and collaborative nature of this work, this thesis is not nearly as comprehensive as I would like. Many of the current research topics are beyond the scope of the thesis, and are not discussed. Expedience had to win over idealism. Many excellent comments by my thesis committee (Michael Littman and Robert Holte in particular) were not addressed in this document, due to time constraints. Revisions (and perhaps additional content) might be available in online versions. The reader is also encouraged to read Morgan Kan's upcoming M.Sc. thesis for an alternate presentation of the DIVAT method discussed in Chapter 5, and some detailed analysis of the Vegas'05 and AAAI'06 competitions (among other things). Numerous people have made significant contributions to this research, however I alone accept the blame for errors and failures to communicate effectively. Darse Billings, September 27, 2006. Acknowledgements I have been truly privileged to work closely with a large team of researchers for many years. In fact, it is fair to say that I have been spoiled, having so much support in developing and implementing my ideas. Consequently, I have many people to thank, and cannot possibly do an adequate job of expressing my gratitude in just a few pages. I could not have asked for a better thesis committee – their feedback and guid- ance has simply been outstanding. Jonathan Schaeffer is the best supervisor I could have ever asked for. He gave me the latitude to create my own research area, to blaze a new path, and to learn from my mistakes along the way. He pushed me when I needed to be pushed. He organized the Computer Poker Research Group (CPRG) to further the research, resulting in more than 20 scientific publications that simply would not have happened otherwise. Apart from his own remarkable achievements, he is a catalyst to the research of all those around him. Although I tease him at every opportunity, it is only because my respect for him runs so deep. Duane Szafron is one of the finest role models I have ever encountered. He is revered by his students for his patience, wisdom, and diligence to their education. His feedback is invaluable for filling gaps, and greatly improving communication. Robert Holte is an excellent person to converse with, not only because of his incredible breadth and depth of knowledge, but also for his many interests and anecdotes. His supervision of Bret Hoehn's M.Sc. thesis provided a comprehen- sive study of opponent modeling in simpler poker domains, illustrating some the inherent challenges and limitations we face. Mike Carbonaro has been a friend for many years, and has provided much encouragement. I am particularly indebted to him for investigating and lobbying for the paper-based thesis option. Although it is a common format in other faculties and universities, this is the first paper-based Ph.D. thesis in Computing Science at the U of A. This option eliminated months of drudgery in re-hashing work that was in some cases more than ten years old. A considerable amount of redundancy is present as a result, but I believe the benefits far outweigh the disadvantages. I hope future students will benefit from the precedent that Mike has championed. Michael Littman has been an inspiration to me since 1998, when he followed my AAAI talk with the single best example I've ever seen of a presentation that is both entertaining and informative. His enthusiasm is infectious, and he is a perfect exemplar of how to do good science and have fun doing it. He provided exten- sive excellent feedback on the dissertation, only some of which I have had time to incorporate. Martin Muller¨ was originally on my thesis committee, but was on sabbatical in Europe at the time of the defense. He provided a lot of valuable feedback on earlier drafts of the dissertation, as well as some insightful words of wisdom about the process. Among my peers, Aaron Davidson has done more than anyone to make me look good. His coding wizardry has had a huge impact on the CPRG. We had way too much fun developing POKI's online personality (responding to conversation, telling jokes, teaching Latin, and on and on). Aaron's online poker server has pro- vided an important venue for empirical testing and data collection. As the lead developer of POKER ACADEMY (www.poker-academy.com), he has helped pro- duce the finest poker training software in the world, by far. Apart from these things, his friendship has enhanced my life in innumerable ways. The other major workhorse for the CPRG has been Neil Burch. He was respon- sible for assimilating the many concepts and details needed to produce SPARBOT. Half of our papers would not have been possible without his tireless efforts running countless experiments. Terry Schauenberg was responsible for merging some vague modeling ideas with a concrete search algorithm to produce our temperamental champion, VEXBOT. He constantly surprises me with his keen insights, and previously unknown areas of expertise. In the past year, Morgan Kan has had an enormous positive impact on my life. He has a knack for asking innocent questions that hit like a punch to the spleen. He is uncompromising in demanding clarity and precision, and equally conscientious in implementation. The DIVAT analysis technique is much stronger as a result of his involvement. All of the members of the CPRG have made significant contributions to the work.
Recommended publications
  • University of Alberta Library Release
    University of Alberta Library Release Form Name of Author: Morgan Hugh Kan Title of Thesis: Postgame Analysis of Poker Decisions Degree: Master of Science Year this Degree Granted: 2007 Permission is hereby granted to the University of Alberta Library to reproduce sin- gle copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. The author reserves all other publication and other rights in association with the copyright in the thesis, and except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatever without the author's prior written permission. Morgan Hugh Kan Date: University of Alberta POSTGAME ANALYSIS OF POKER DECISIONS by Morgan Hugh Kan A thesis submitted to the Faculty of Graduate Studies and Research in partial ful- fillment of the requirements for the degree of Master of Science. Department of Computing Science Edmonton, Alberta Spring 2007 University of Alberta Faculty of Graduate Studies and Research The undersigned certify that they have read, and recommend to the Faculty of Grad- uate Studies and Research for acceptance, a thesis entitled Postgame Analysis of Poker Decisions submitted by Morgan Hugh Kan in partial fulfillment of the re- quirements for the degree of Master of Science. Jonathan Schaeffer Supervisor Michael Bowling Michael Carbonaro External Examiner Date: To my parents, Janet and Chay Kan, and my sister, Megan Kan, I would never have made it this far without them. Abstract In Artificial Intelligence research, evaluation is a recurring theme. A newly crafted game-playing program is interesting if it can be shown to be better by some mea- sure.
    [Show full text]
  • SCIENCE VOLUME 18, No 2, FALL 2007
    SCIENCE VOLUME 18, No 2, FALL 2007 FACULTY OF SCIENCE ALUMNI MAGAZINE contourswww.ualberta.ca/science UNIVERSITY Reading CREATES our body’s SPACE chemicals for INSTITUTE better diagnosis Honouring Mama ALUMNUS TURNS Lu’s spirit of GRIEF INTO HOPE giving Fine arts ARCTIC PONDS students liven DRYING UP up lab space through games SCIENCEcontours Science Contours is published twice MESSAGE FROM THE DEAN a year by the faculty of Science to provide current information on its many activities. The magazine is distributed to alumni and friends of the Faculty of An Intersection Between Arts and Science Science. Phase 1 of our new Dean of Science Centennial Centre for Gregory Taylor Interdisciplinary Sci- ence (CCIS) was near- Assistant Dean, External Relations Claudia Wood ing completion when I happened upon a stu- External Relations Team dent art competition on Katherine Captain, Emily Lennstrom, campus. It occurred to Michel Proulx, Traci Toshack, me then that it would be Kevin Websdale wonderful to have stu- Fine arts students Editor dents help us put some Wendy Lung and Ansun Michel Proulx finishing touches on our Yan enjoy their work new space. Graphic Design After a few conversations, two different classes - one in Inte- Studio X Design grative/Exhibit Design and the other in Printmaking - were tasked with coming up with ideas. The results are astounding. Contributing writers To begin with, the students had to wrap their heads around the Bev Betkowski, Kris Connor, Michel purpose and uniqueness of the building. CCIS is one of the few Proulx, Isabela Varela facilities in the world to house interdisciplinary teams under one roof and Phase 1 is no different.
    [Show full text]
  • Building a Champion Level Computer Poker Player
    University of Alberta Library Release Form Name of Author: Michael Bradley Johanson Title of Thesis: Robust Strategies and Counter-Strategies: Building a Champion Level Computer Poker Player Degree: Master of Science Year this Degree Granted: 2007 Permission is hereby granted to the University of Alberta Library to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. The author reserves all other publication and other rights in association with the copyright in the thesis, and except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatever without the author’s prior written permission. Michael Bradley Johanson Date: Too much chaos, nothing gets finished. Too much order, nothing gets started. — Hexar’s Corollary University of Alberta ROBUST STRATEGIES AND COUNTER-STRATEGIES: BUILDING A CHAMPION LEVEL COMPUTER POKER PLAYER by Michael Bradley Johanson A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science. Department of Computing Science Edmonton, Alberta Fall 2007 University of Alberta Faculty of Graduate Studies and Research The undersigned certify that they have read, and recommend to the Faculty of Graduate Studies and Research for acceptance, a thesis entitled Robust Strategies and Counter-Strategies: Building a Champion Level Computer Poker Player submitted by Michael Bradley Johanson in partial fulfillment of the requirements for the degree of Master of Science. Michael Bowling Supervisor Duane Szafron Michael Carbonaro External Examiner Date: To my family: my parents Brad and Sue Johanson, and my brother, Jeff Johanson.
    [Show full text]
  • The Game Stats Appendix A: Further Reading
    The Game Stats Appendix A: Further Reading Checkers Organizations American Checker Federation (ACF). http://usacheckers.com. Membership in- cludes the bimonthly ACF Bulletin. English Draughts Association (EDA). http://home.clara.net/davey. Membership includes the occasional English Draughts Journal. Checkers Irving Chernev, The Compleat Draughts Player, Oxford University Press, 1981. A readable and instructive book including the history of the game, openings, strate- gies, endgames, problem solving, and classic games. Chernev is one of the few players to reach the title of master in both chess and checkers. Robert Pike, Checker Power: A Game of Problem Solving, Charlesbridge Pub- lishing, 1997. Pike has authored a series of readable books on using checkers for problem solving (and fun). Robert L. Schuffett, Checkers the Tinsley Way, published privately, 1982. Avail- able through the ACF. This book contains over seven hundred of Tinsley’s games, along with pictures, anecdotes, and statistics from his remarkable career. Richard Pask, The Legendary MFT, Checkered Thinking, 2007. Available at http://www.bobnewell.net/nucleus/checkers.php. The most comprehensive collec- tion of material on Tinsley. Richard Fortman, Basic Checkers, seven volumes, privately published. Available from the ACF and at http://home.clara.net/davey/basicche.html. A detailed intro- duction to the main lines of play of the three-move ballot openings. Computer Checkers History Christopher Strachey, “Digital Computers Applied to Games,” Faster Than Thought, B.V. Bowden (editor), Pitman & Sons, London, 1953. Arthur Samuel, “Some Studies in Machine Learning Using the Game of Check- ers,” IBM Journal of Research and Development 3, 1959, pp. 210-229.
    [Show full text]
  • CHINOOK the World Man-Machine Checkers Champion
    AI Magazine Volume 17 Number 1 (1996) (© AAAI) Articles CHINOOK The World Man-Machine Checkers Champion Jonathan Schaeffer, Robert Lake, Paul Lu, and Martin Bryant ■ In 1992, the seemingly unbeatable World Check- the American Checker Federation (ACF), CHI- er Champion Marion Tinsley defended his title NOOK was allowed to play in the 1990 U.S. against the computer program CHINOOK. After an championship. This biennial event attracts intense, tightly contested match, Tinsley fought the best players in the world, with the winner back from behind to win the match by scoring earning the right to play a match for the four wins to CHINOOK’s two, with 33 draws. This match was the first time in history that a human world championship. world champion defended his title against a com- CHINOOK came in an undefeated second in puter. This article reports on the progress of the the tournament behind the world champion, checkers (8 3 8 draughts) program CHINOOK since Marion Tinsley. The four individual games 1992. Two years of research and development on between CHINOOK and Tinsley were drawn. the program culminated in a rematch with Tins- This placing earned CHINOOK the right to chal- ley in August 1994. In this match, after six games lenge Tinsley for the world championship, (all draws), Tinsley withdrew from the match and the first time a computer had earned such a relinquished the world championship title to CHI- right in any game. NOOK, citing health concerns. CHINOOK has since defended its title in two subsequent matches. It is Tinsley emerged as a dominant player in the first time in history that a computer has won the late 1940s.
    [Show full text]
  • Best-First and Depth-First Minimax Search in Practice
    Best-First and Depth-First Minimax Search in Practice Aske Plaat, Erasmus University, [email protected] Jonathan Schaeffer, University of Alberta, [email protected] Wim Pijls, Erasmus University, [email protected] Arie de Bruin, Erasmus University, [email protected] Erasmus University, University of Alberta, Department of Computer Science, Department of Computing Science, Room H4-31, P.O. Box 1738, 615 General Services Building, 3000 DR Rotterdam, Edmonton, Alberta, The Netherlands Canada T6G 2H1 Abstract Most practitioners use a variant of the Alpha-Beta algorithm, a simple depth-®rst pro- cedure, for searching minimax trees. SSS*, with its best-®rst search strategy, reportedly offers the potential for more ef®cient search. However, the complex formulation of the al- gorithm and its alleged excessive memory requirements preclude its use in practice. For two decades, the search ef®ciency of ªsmartº best-®rst SSS* has cast doubt on the effectiveness of ªdumbº depth-®rst Alpha-Beta. This paper presents a simple framework for calling Alpha-Beta that allows us to create a variety of algorithms, including SSS* and DUAL*. In effect, we formulate a best-®rst algorithm using depth-®rst search. Expressed in this framework SSS* is just a special case of Alpha-Beta, solving all of the perceived drawbacks of the algorithm. In practice, Alpha-Beta variants typically evaluate less nodes than SSS*. A new instance of this framework, MTD(ƒ), out-performs SSS* and NegaScout, the Alpha-Beta variant of choice by practitioners. 1 Introduction Game playing is one of the classic problems of arti®cial intelligence.
    [Show full text]
  • Man Versus Machine. . . for the World Checkers Championship
    AI Magazine Volume 14 Number 2 (1993) (© AAAI) Articles Man Versus Machine . 28 AI MAGAZINE Articles . for the World Checkers Championship Jonathan Schaeffer, Norman Treloar, Paul Lu, and Robert Lake ■ In August 1992, the world checkers champion, with CHINOOK before we can expect to defeat Marion Tinsley, defended his title against the Tinsley in a match, but the close score and computer program CHINOOK. Because of its success the two wins represent a milestone from the in human tournaments, CHINOOK had earned the computing point of view. right to play for the world championship. Tinsley CHINOOK is the first program to play for a won the best-of-40-game match with a score of 4 human world championship in a nontrivial wins, 2 losses, and 33 draws. This event was the first time in history that a program played for a game of skill. Computers have played world human world championship and might be a pre- champions before, for example, DEEP THOUGHT lude to what is to come in chess. This article tells in chess (Hsu et al. 1990) and BKG9 in the story of the first Man versus Machine World backgammon (Berliner 1980), but they were Championship match. exhibition matches with no title at stake. Tinsley is to be congratulated for putting his t has been 30 years since Arthur Samuel’s reputation on the line against a computer. (1967, 1959) pioneering efforts in machine This match might be a prelude to what will Ilearning gave prominence to checkers- eventually happen in chess. playing programs. Samuel’s successes includ- ed a victory by his program over a The Champion master-level player.
    [Show full text]
  • Games History.Key
    Artificial Intelligence: A History of Game-Playing Programs Nathan Sturtevant AI For Traditional Games With thanks to Jonathan Schaeffer What does it mean to be intelligent? How can we measure computer intelligence? Nathan Sturtevant When will human intelligence be surpassed? Nathan Sturtevant When will human intelligence be surpassed? Human strengths Computer Strengths • Intuition • Fast, precise computation • Visual patterns • Large, perfect memory • Deeply crafted knowledge • Repetitive, boring tasks • Experience applied to new situations Nathan Sturtevant When will human intelligence be surpassed? Nathan Sturtevant When will human intelligence be surpassed? Why games? Focus • Well defined • How did the computer AI win? • Well known • How did the humans react? • Measurable • What mistakes were made in over-stating performance • Only 60 years ago it was an open question whether computers could play games • Game play was thought to be a creative, human activity, which machines would be incapable of Nathan Sturtevant When will human intelligence be surpassed? Nathan Sturtevant When will human intelligence be surpassed? Checkers History • Arthur Samuel began work on Checkers in the late 50’s • Wrote a program that “learned” to play • Beat Robert Nealey in 1962 • IBM advertised as “a former Connecticut checkers champion, and one of the nation’s foremost players” • Nealey won rematch in 1963 • Nealey didn’t win Connecticut state championship until 1966 • Crushed by human champions in 1966 Nathan Sturtevant When will human intelligence be surpassed? Reports of success overblown Human Champ: Marion Tinsley • “...it seems safe to predict that within • “Computers became unbeatable in ten years, checkers will be a completely checkers several years ago.” Thomas • Closest thing to perfect decidable game.” Richard Bellman, Hoover, “Intelligent Machines,” Omni human player Proceedings of the National Academy of magazine, 1979, p.
    [Show full text]
  • Poker Learner: Reinforcement Learning Applied to Texas Hold'em
    FACULDADE DE ENGENHARIA DA UNIVERSIDADE DO PORTO Poker Learner: Reinforcement Learning Applied to Texas Hold’em Poker Nuno Miguel da Silva Passos Master in Informatics and Computer Engineering Supervisor: Luís Paulo Reis (Ph.D.) Co-Supervisor: Luís Teófilo (Ms. C.) 18th July, 2011 © Nuno Passos, 2011 Poker Learner: Reinforcement Learning Applied to Texas Hold’em Poker Nuno Miguel da Silva Passos Master in Informatics and Computing Engineering Approved in oral examination by the committee: Chair: António Coelho (Ph. D.) External Examiner: Luís Correia (Ph. D.) Supervisor: Luís Paulo Reis (Ph. D.) ____________________________________________________ 18th July, 2011 Resumo Os jogos sempre foram uma área de interesse para a inteligência artificial, especialmente devido às suas regras simples e bem definidas e a necessidade de estratégias complexas para garantir a vitória. Vários investigadores da área das ciências da computação dedicaram o seu tempo no estudo de jogos como o Xadrez ou Damas, obtendo resultados notáveis, tendo desenvolvido jogadores artificiais capazes de derrotar os melhores jogadores humanos. Na última década, o Poker tornou-se num fenómeno de popularidade crescente a nível mundial, comprovado pelo aumento consideravel do número de jogadores nos casinos online, tornando o Poker numa indústria bastante rentável. Na área de investigação da inteligência artificial, o Poker também tornou-se igualmente num domínio interessante devido à natureza estocástica e de informação incompleta do jogo. Por estes motivos, Poker apresenta-se como uma boa plataforma para desenvolver e testar soluções para desafios presentes na área de inteligência artificial, como o tratamento de informação incompleta do ambiente e a possibilidade de existirem elementos aleatórios no mesmo.
    [Show full text]
  • Solving the Game of Checkers
    Games of No Chance MSRI Publications Volume 29, 1996 Solving the Game of Checkers JONATHAN SCHAEFFER AND ROBERT LAKE Abstract. In 1962, a checkers-playing program written by Arthur Samuel defeated a self-proclaimed master player, creating a sensation at the time for the fledgling field of computer science called artificial intelligence. The historical record refers to this event as having solved the game of checkers. This paper discusses achieving three different levels of solving the game: publicly (as evidenced by Samuel’s results), practically (by the checkers program Chinook, the best player in the world) and provably (by consid- ering the 5 1020 positions in the search space). The latter definition may be attainable× in the near future. 1. Introduction Checkers is a popular game around the world, with over 150 documented variations. Only two versions, however, have a large international playing com- munity. What is commonly known as checkers (or draughts) in North America is widely played in the United States and the British Commonwealth. It is played on an 8 8 board, with checkers moving one square forward and kings moving one × square in any direction. Captures take place by jumping over an opposing piece, and a player is allowed to jump multiple men in one move. Checkers promote to kings when they advance to the last rank of the board. So-called international checkers is popular in the Netherlands and the former Soviet Union. This vari- ant uses a 10 10 board, with checkers allowed to capture backwards, and kings × allowed to move many squares in one direction, much like bishops in chess.
    [Show full text]
  • Lecture Notes in Computer Science Edited by J
    Lecture Notes in Artificial Intelligence 1418 Subseries of Lecture Notes in Computer Science Edited by J. G. Carbonell and J. Siekmann Lecture Notes in Computer Science Edited by G. Goos, J. Hartmanis and J. van Leeuwen Robert E. Mercer Eric Neufeld (Eds.) Advances in A'~"rtltlClal " "Intelligence 12th Biennial Conference of the Canadian Society for Computational Studies of Intelligence, AI'98 Vancouver, BC, Canada, June 18-20, 1998 Proceedings ~ Springer Series Editors Jaime G. Carbonell, Carnegie Melton Universit~ Pittsburgh, PA, USA Jfrg Siekmann, University of Saarland, Saarbriicken, Germany Volume Editors Robert E. Mercer Department of Computer Science, University of Western Ontario London, ON, N6A 5B7, Canada E-mail: [email protected] Eric Neufetd Department of Computer Science, University of Saskatchewan 57 Campus Drive, Saskatoon, SK, S7N 5A9, Canada E-mail: [email protected] Cataloging-in-Publication Data applied for Die Deutsche Bibliothek - CIP-Einheitsaufnahme Advances in artificial intelligence : proceedings / AI '98, Vancouver, BC, Canada, June 18 - 20, 1998. Robert Mercer ; Eric Neufeldt (ed.). - Berlin ; Heidelberg ; New York ; Barcelona ; Budapest ; Hong Kong ; London ; Milan ; Paris ; Santa Clara ; Singapore ; Tokyo : Springer, 1998 (... biennial conference of the Canadian Society for Computational Studies of Intelligence ; 12) (Lecture notes in computer science ; Vol. 1418 : Lecture notes in artificial intelligence) ISBN 3-540-64575-6 CR Subject Classification (1991): 1.2 ISBN 3-540-64575-6 Springer-Verlag Berlin Heidelberg New York This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, re-use of illustrations, recitation, broadcasting, reproduction on microfilms or in any other way, and storage in data banks.
    [Show full text]
  • Chinook: the World Man-Machine Checkers Champion
    Chinook: The World Man-Machine Checkers Champion Jonathan Schaeffer, Robert Lake, Paul Lu and Martin Bryant ABSTRACT In 1992, the seemingly unbeatable World Checker Champion, Dr. Marion Tinsley, defended his title against the computer program Chinook. After an intense, tightly-contested match, Tinsley fought back from behind to win the match by scoring four wins to Chinook's two, with 33 draws. This was the first time in history that a human World Champion defended his title against a computer. This article reports on the progress of the checkers (8×8 draughts) program Chinook since 1992. Two years of research and development on the program culminated in a rematch with Tinsley in August 1994. In that match, after six games (all draws), Tinsley resigned the match and the World Cham- pionship title to Chinook citing health concerns. Chinook has since defended its title in two subsequent matches. This is the first time in history that a com- puter has won a human World Championship. Keywords: game-playing, alpha-beta, heuristic search, checkers. 1. Background The most well-known checkers-playing program was Samuel's effort in the period around 1955-1965 (Samuel 1967; Samuel 1959). This work remains a milestone in artif- icial intelligence research. Samuel's program reportedly beat a master and "solved" the game of checkers. Both journalistic claims are false, but they served to create the impression that there was nothing of scientific interest left in the game (Samuel himself made no such claims). Consequently, most subsequent games-related research turned to chess. Other than a program from Duke University in the 1970's (Truscott 1979), little attention was paid to achieving a World Championship caliber checkers program.
    [Show full text]