Robert Lake

Checkers Is Solved

The game of checkers has roughly 500 billion billion possible positions (5 × 1020). The task of solving the game, determining the final result in a game with no mistakes made by either player, is daunting. Since 1989, almost continuously, dozens of computers have been working on solving checkers, applying state-of-the-art artificial intelligence techniques to the proving process. This paper announces that checkers is now solved: Perfect play by both sides leads to a draw. This is the most challenging popular game to be solved to date, roughly one million times as complex as Connect Four. Artificial intelligence technology has been used to generate strong heuristic-based game-playing programs, such as Deep Blue for chess. Solving a game takes this to the next level by replacing the heuristics with perfection.

CHINOOK The World Man-Machine Checkers Champion

In 1992, the seemingly unbeatable World Checker Champion 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 CHINOOKs two, with 33 draws. This match 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 3 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 this match, after six games (all draws), Tinsley withdrew from the match and relinquished the world championship title to CHINOOK,citing health concerns. CHINOOK has since defended its title in two subsequent matches. It is the first time in history that a computer has won a human-world championship.

Near-Real-Time Control of Human Figure Models

Animating human figures is one of the major problems in computer animation. A recent approach is the use of dynamic analysis to compute the movement of a human figure, given the forces and torques operating within and upon the body. One of the problems with this technique is computing the forces and torques required for particular motions; this has been called the control problem of dynamic analysis. To develop a better understanding of this problem, an interactive interface to a dynamics package has been produced. This interface, along with a collection of low-level motion processes, can be used to control the motion of a human figure model. This article describes both the user interface and the motion processes, along with our experiences with this approach.

Norovirus Genotype Profiles Associated with Foodborne Transmission, 1999-2012

Foodborne transmission accounts for 10% of outbreaks caused by GII.4, 27% by all other single genotypes, and 37% by mixtures of GII.4 and others

Solving Large Retrograde Analysis Problems Using a Network of Workstations

Chess endgame databases, while of important theoretical interest, have yet to make a significant impact in tournament chess. In the game of checkers, however, endgame databases have played a pivotal role in the success of our World Championship challenger program Chinook. Consequently, we are interested in building databases consisting of hundreds of billions of positions. Since database positions arise frequently in Chinook’s search trees, the databases must be accessible in real-time, unlike in chess. This paper discusses techniques for building large endgame databases using a network of workstations, and how this data can be organized for use in a real-time search. Although checkers is used to illustrate many of the ideas, the techniques and tools developed are also applicable to chess.

Building the Checkers 10-Piece Endgame Databases

In 1993, the Chinook team completed the computation of the 2 through 8-piece checkers endgame databases, consisting of roughly 444 billion positions. Until recently, nobody had attempted to extend this work. In November 2001, we began an effort to compute the 9- and 10-piece databases. By June 2003, the entire 9-piece database and the 5-piece versus 5-piece portion of the 10-piece database were completed. The result is a 13 trillion position database, compressed into 148 GB of data organized for real-time decompression. This represents the largest endgame database initiative yet attempted. The results obtained from these computations are being used to aid an attempt to weakly solve the game. This paper describes our experiences working on building large endgame databases.

Declining Guillain-Barré Syndrome after Campylobacteriosis Control, New Zealand, 1988-2010

Food safety measures that lower incidence of campylobacteriosis might also prevent Guillain-Barré syndrome.

Man Versus Machine for the World Checkers Championship

In August 1992, the world checkers champion, Marion Tinsley, defended his title against the computer program CHINOOK. Because of its success in human tournaments, CHINOOK had earned the right to play for the world championship. Tinsley won the best-of-40-game match with a score of 4 wins, 2 losses, and 33 draws. This event was the first time in history that a program played for a human world championship and might be a prelude to what is to come in chess. This article tells the story of the first Man versus Machine World Championship match.

Willingness of University Nursing Students to Volunteer During a Pandemic

OBJECTIVE The global threat of an influenza pandemic continues to grow and thus universities have begun emergency preparedness planning. This study examined stakeholders knowledge, risk-perception, and willingness to volunteer. DESIGN AND SAMPLE The design of this study is a cross-sectional survey. Questionnaires were sent to 1,512 nursing students and were returned by 484, yielding a response rate of 32% for this subgroup. Nursing students may be a much-needed human resource in the event of an influenza pandemic. MEASURES The measurement tool was a Web-based questionnaire regarding pandemic influenza designed by a subgroup of researchers on the Public Health Response Committee. RESULTS Most nursing students (67.9%) said they were likely to volunteer in the event of a pandemic if they were able to do so. An even higher number (77.4%) said they would volunteer if provided protective garments. Overall, 70.7% of students supported the proposition that nursing students have a professional obligation to volunteer during a pandemic. Nursing students indicated that they have had a wealth of volunteer experience in the past and they would apply this service ethic to a pandemic situation. CONCLUSIONS Emergency preparedness competencies should be integrated into existing nursing curricula and other health science programs. University administrations need to engage in planning to create protocol for recruitment, practice, and protection of volunteers.

Medical Students and Pandemic Influenza

To assess knowledge of pandemic influenza, we administered a questionnaire to all medical students at the University of Alberta; 354 (69%) of 510 students responded. Data from questionnaires such as this could help determine the role of medical students during a public health emergency.