About KCEC

Introduction

KCEC stands for "Kirr's Chess Engine Comparison". It is a tournament of free single-CPU chess engines. All games are also submitted to CCRL 40/4. KCEC ratings are calibrated to CCRL 40/4 rating list from 2008-07-25 using all shared engines.

Participation

This is a tournament of free original single-CPU engines. More specifically, each participating program must meet the following requirements:

• Windows binary is freely available for everyone to download and use.
• Original work (within reason, 3-rd party EGTB code is OK, for example).
• Able to disable its own opening book (if any).
• Able to run with ponder off.
• Able to use only 1 core on a multi-core machine.
• Able to play with repeating 40/4 time control.
• Reasonably complete and stable.

Tournament Format

• Each engine has to play at least 30 games with at least 16 nearest higher rated opponents and at least 16 nearest lower rated opponents (if exist). This results in at least 960 games played by an engine in the middle of the list, and at least 480 games played by the highest or lowest rated engine.
• At most two entries by the same author may participate in the rating calculation. When a new version enters the tournament, if two versions were already listed, the older one will be removed (with all its games).
• Only the latest version of each engine participates in ranking. Even if it is currently rated lower then the previous version.
• Engines are added one by one. After an engine has played all the necessary matches with nearby opponents, the next engine can be introduced.

Testing Conditions

• Time Control: Equivalent to 40 moves in 4 minutes on AMD X2 4600+ at 2.4GHz. Crafty 19.17 BH (Brian Hoffman's compile) is used as a benchmark to determine the equivalent time control for particular machine. Time control is perpetually repeating: An engine receives another 4 minutes on move 41, on move 81, and so on.

• Pondering: OFF.
• Number of threads (or CPUs): 1 for all engines.
• Hash tables size: 128 MB or the nearest possible smaller size.
• Opening book: Any neutral book (not tuned to any particular engine), limited to 8 moves for each side. The same book is used for both sides in any game. Engine's own books are disabled.
• Book learning: OFF.
• Position learning: OFF.
• Endgame tablebases: Eugene Nalimov's tablebases and all engine's own format tablebases are provided, for up to 5-piece endgames. EGTB hash size is set to 32 MB where applicable.
• Adjudication by winning evaluation: OFF.
• Adjudication by EGTB: OFF.
• Adjudication by drawing evaluation: LATE (or OFF).