Match Kasparov - Topalov
Leon (Spain)
10 - 13 June 1998

RULES OF THE MATCH

Advanced Chess
Advanced Chess is a new form of chess in which humans and computers join forces and compete as a team against each other. It represents a very high-tech approach to the game and increases the level of play to heights never before seen in chess. It also gives the viewing public a unique insight into the thought processes of chess playing humans and computers.

Background
Chess is a game played by two entities on the planet: man and the digital computer. Initially humans completely outclassed the machines, but in recent years computers have made dramatic progress in playing strength. Today a standard PC with a disk-based program is able to beat 99.999% of all human chess players.

Strength of the computer
Computers calculate at prodigious speeds. On a fast PC the strongest chess programs will generate and evaluate about 150,000 positions per second. In tactically complex positions they are superior to any human player. In the opening they can access unlimited knowledge from disk -literally millions of tried and tested moves. In the endgame they use hash tables to search very deeply, and in certain restricted endings (with just five pieces on the board) they in fact possess total information and play absolutely perfect chess.

Human strength
Human masters look at only a very limited number of positions, compared to a computer, but they are able to sort out the relevant from the irrelevant, look at meaningful moves instead of every non-sensical variation. Human are able to judge the quality of a move in very long-term categories, formulate plans that go a long way beyond the horizons of even the fastest computers. If a human chess master can survive the tactical onslaught of the machine, his strategical superiority will triumph.

Effect of computers on human players
Because of their playing strength and general availability, computers have a profound influence on chess players of all categories. Computers are used to practice and train, to develop new opening plans, analyze complex positions, solve difficult endings. Owing a fast PC today is like having a Grandmaster at your permanent disposal.

Computers have also changed the way serious chess tournaments are conducted. Any contact between players and their electronic helpers must be prevented during the game. The tradition of interrupting long games and completing them a day or some days later, had to be abandoned as it became possible to exhaustively analyze the position with the help of computers. In correspondence chess, where the players work on their moves for many days in the privacy of their homes, computers are used extensively  although most correspondence players will not admit to his.

The symbiosis: man and machine
Advanced Chess makes a virtue out of the reality of chess playing computers. Each human player is equipped with a PC, which he can consult at will during the game. The rate of play is one hour for all moves, so that the player must be agile and allocate his time well. He enters moves for the computer to analyze, spends time pondering the position himself, while the computer is checking the crucial variations. The Human is always in charge and has the final decision on which move to make.

Tournament players have identical hardware  the latest and fastest PCs- which help select the moves. They use computers differently in three phases of the game:

Strength of the Advanced Chess player
It is important to note that the human-computer team is stronger than each of its components. A top Grandmaster may be considerably stronger than the computer program he is using, but he is able to increase his playing strength even further when assisted by the program. Experts have estimated that the best man-computer teams may be able to achieve a truly incredible performance of 3000 on the Elo scale (the world s strongest player, Garry Kasparov, has just reached a record rating of 2820.

Displaying the thinking process
A feature of Advanced Chess is that for the first time, the public will be able to directly observe how top Grandmasters find their moves. The monitor displays of both players are projected on large screens, so that the audience can follow every action. In the analysis room, a chess commentator, with a third computer  with the same program as the players   will explain exactly why certain lines were rejected by the players.

Special software and hardware
In Advanced Chess, special software will be made available to the players, allowing fast access to the information they require. They can consult hundreds of thousands of games at the click of the mouse, view multiple variations generated by the chess engine, and access gigabytes of endgame positions. In the future it will be possible to increase the power of hardware by using multiple processor systems, with each CPU dedicated to analyzing a different line of play. It will be interesting for computer manufacturers to make this newest technology available for Advanced Chess, since this is an area in which every increase in computing speed translates directly into an increase in the playing strength of the man-machine team.