The 2005 Arimaa Postal Championship
Tournament Rules

Who can participate
Anyone may play in the tournament; including Arimaa playing programs (bots). Everyone including bots will be eligible for prizes.

Tournament Rules
The time control for all games played in this tournament will be: 1d/14d/100/14d/300d.

Each player will play against a maximum of 10 other players. All games will be played simultaneously.

If the number of players in the tournament is 11 or less then each player will play one game against each of the other players.

If the number of players is more than 11 then each player will play against players that are close in rating. This is done as follows. First the players are ordered according to rating. If two or more players have the same rating they are ordered alphabetically by username. If there are N players they are positioned with the highest rated player in position 1, the second highest in position N, the third highest in position 2, the 4th highest in position N-1, and so on. Position 1 and N are connected to form a ring. Each player plays the 5 players on the right and the 5 players on the left (higher numbered positions are on the right and lower numbered positions are on the left for the player at N/2). The player will play gold against the first player on the right, silver against the second player on the right and so on alternating colors. When playing an opponent on the opposite side of the ring, the lower rated player will be gold. If the ratings are the same then the player in the lower numbered position will be gold.

In case the game is not completed within the allowed time the Arimaa scoring method is used to determine a winner. It is highly unlikely that the game will have to be determined by score.

Players receive 1 point for a win, 0.5 point for a draw and 0 for a loose. The player with the most points wins the tournament. In case of a tie, the player who has the lowest average moves per game for won games is considered the winner. If this is still a tie than the higher rated player is considered the winner. Second and third place are also determined similarly.

Prize Distribution Rules
The total registration fees collected are put into a shared pool and distributed after the tournament in proportion to the number of points the player has accumulated.

A player who wins all the games will get back about 160% of their registration fee. A player who loses all the games by goal in appoximately 50 moves will still get back about 40% of their registration fee.

Special Rules for Humans
Since these are postal games and there is ample time for a player to think about the moves, the players must be careful to make sure that the moves they make are truly moves that were produced by them. A player must be careful not to discuss the game or a particular move with anyone else. A player must not imitate the moves from one game over to another game. A player must not use a computer program to suggest or evaluate moves. Although a player may use the 'Plan' option provided in the game window to plan out a move without input from any other source.

Special Rules for Bots
In order to keep all the bots on an equal playing field, the bots must be run on only one off-the-shelf computer system that can be purchased within $1000 USD. The bots will need to declare before the start of the tournament what hardware they will be running on. The hardware may not be changed after the tournament begins. Also the bot program must not be changed or updated after the tournament begins. The program may modify itself in an automated manner, but it may not be manually altered.

Notes
The games cannot be adjourned and must be completed once they are started. A player will not be allowed to take back a move once it has been submitted. The games will be rated and will contribute to the players' ratings. The director will serve as the arbitrator in case of disputes. Should a dispute arise about the outcome of a game, or of a player not following the rules, the director will review the eveidence and provide a decision to resolve the situation. The directors' decision shall be considered final and binding by all parties.

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