Yet another world champion has been brought low for suspected use of a banned performance-enhancing substance.
Rybka, the chess-playing computer program that won the past four World Computer Chess Championship titles, was summarily stripped of its silicon crown this week amid charges its programmer plagiarized the software of two rival programs.
David Levy, president of the International Computer Games Association (ICGA), announced the action against Rybka on Wednesday and imposed a lifetime ban on Czech-American programmer and Massachusetts Institute of Technology graduate Vasik Rajlich. He accused Mr. Rajlich of ripping off the coding of two other software programs marketed as Crafty and Fruit. Mr. Levy also demanded the return of trophies and prize money the program won.
“We are convinced that the evidence against Vasik Rajlich is both overwhelming in its volume and beyond reasonable question in its nature. Vasik Rajlich is guilty of plagiarizing the programs Crafty and Fruit,” an ICGA letter states.
As accusations have mounted in recent months about the sources of Rybka’s phenomenal playing strength, Mr. Rajlich has steadily maintained his innocence on various online chess forums but given no formal denial. Now reportedly living in Warsaw, he did not respond to email requests for comment Thursday.
Mr. Levy also released eight comprehensive evaluations of the programs in comparison, put together by specialists who used Mr. Rajlich’s own words on how easy it is to copy programming source code to emphasize their point. The evaluations show identical coding in numerous aspects of Rybka and the earlier programs.
“The Rybka code base was without doubt derived directly from other people’s work and this was never revealed, so this is [a] case of taking credit for the work of others and it shows a lack of respect for the other major talents in computer chess as well as the ICGA and organizers of these events,” Don Dailey, a fellow computer chess programmer, wrote in one report.
Mr. Dailey was also one of 14 co-authors of a letter sent to the ICGA in March accusing Rybka of copying Fruit, an “open-source” program created by Frenchman Fabien Letouzey that was runner-up world computer champion in 2005.
Rybka won four consecutive World Computer Chess Championship titles from 2007 to 2010. But questions of programming ethics and stolen codes still bedevil the field.
Since the epic 1997 match in which IBM program Deep Blue defeated human world champion Garry Kasparov, computer-playing programs have far outstripped their flesh-and-blood rivals. Today, even widely available programs with names such as Fritz, Hiarcs and Deep Junior play at a much higher rating than even the strongest grandmasters.
Peter Doggers, the editor of popular chess website Chessvibes.com, said there are now maybe hundreds of computer programs that can play chess and are routinely used as training aids and superstrong sparring partners for players.
“These days, there’s no serious professional chess player in the world’s top 100 who doesn’t use a computer to assist him in analyzing his games and preparing for new games,” Mr. Doggers said.
But with the flood of technology has come some modern ethical dilemmas for the ancient game.
Mr. Kasparov and his backers accused Deep Blue of getting help from human programmers for moves at key points in the 1997 match and demanded - unsuccessfully - to see the computer’s calculating records.
With the advent of smartphones and palm-sized computers, there have been repeated instances of players caught getting moves transmitted to them during tournament games. A 2008 world championship match was nearly derailed after one contestant questioned the frequent bathroom breaks being taken by his opponent.