Top Chess Engine Championship, formerly known as Thoresen Chess Engines Competition (TCEC or nTCEC), is a

computer chess Computer chess includes both hardware (dedicated computers) and software capable of playing chess. Computer chess provides opportunities for players to practice even in the absence of human opponents, and also provides opportunities for analysi ...

tournament that has been run since 2010. It was organized, directed, and hosted by Martin Thoresen until the end of Season 6; from Season 7 onward it has been organized by Chessdom. It is often regarded as the ''Unofficial World Computer Chess Championship'' because of its strong participant line-up and long time-control matches on high-end hardware, giving rise to very high-class chess. The tournament has attracted nearly all the top engines compared to the

World Computer Chess Championship World Computer Chess Championship (WCCC) is an event held periodically since 1974 where computer chess engines compete against each other. The event is organized by the International Computer Games Association. It is often held in conjunction with ...

. After a short break in 2012, TCEC was restarted in early 2013 (as ''nTCEC'') and is currently active (renamed as TCEC in early 2014) with 24/7 live broadcasts of chess matches on its website. Since season 5, TCEC has been sponsored by Chessdom Arena.

Overview

Basic structure of competition

The TCEC competition is divided into seasons, where each season happens over a course of a few months, with matches played round-the-clock and broadcast live over the internet. Each season is divided into several tournaments: a Leagues Season, a Cup, a

Swiss tournament A Swiss-system tournament is a non-eliminating tournament format that features a fixed number of rounds of competition, but considerably fewer than for a round-robin tournament; thus each competitor (team or individual) does not play all the other ...

, a

Fischer Random Chess Fischer random chess, also known as Chess960 (often read in this context as 'chess nine-sixty' instead of 'chess nine hundred sixty'), is a variation of the game of chess invented by the former world chess champion Bobby Fischer. Fischer announ ...

tournament. Additionally, seasons contain various bonus contests, like the 'Viewer Submitted Opening Bonus'. Prior to season 21, there was originally one tournament in each season. This tournament consisted of several qualifying stages and one "superfinal", and the winner of the superfinal is called the "TCEC Grand Champion" until the next season. Prior to season 11, the tournament used a cup format, while starting in Season 11, the tournament used a division system. Starting in season 13, there was also a cup tournament consisting of the top 32 engines in the main tournament, resulting in a 5-round single elimination tournament.

Engine settings/characteristics

Pondering In turn-based games, permanent brain (also called pondering) is the act of thinking during the opponent's turn. Chess engines that continue calculating even when it is not their turn to play end up choosing moves that are stronger than if they are ...

is set to off. All engines run on mostly the same hardware and use the same

opening book A chess opening book is a book on chess openings. This is by far the most common type of literature on chess. These books describe many major lines, like the Sicilian Defence, Ruy Lopez, and Queen's Gambit, as well many minor variations of the ma ...

, which is set by the organizers and changed in every stage.

Large pages A page, memory page, or virtual page is a fixed-length contiguous block of virtual memory, described by a single entry in the page table. It is the smallest unit of data for memory management in a virtual memory operating system. Similarly, a p ...

are disabled, but access to various

endgame tablebases An endgame tablebase is a computerized database that contains precalculated exhaustive analysis of chess endgame positions. It is typically used by a computer chess engine during play, or by a human or computer that is retrospectively analysin ...

is permitted. Engines are allowed updates between stages; if there is a critical play-limiting bug, they are also allowed to be updated once during the stage. In previous seasons, if an engine crashes 3 times in one event, it is disqualified to avoid distorting the results for the other engines; however starting in TCEC Season 20, an engine is allowed to crash as many times as possible without being disqualified from the current event; however, the engine will still be disqualified from future events unless the crash is fixed. TCEC generates an

Elo rating The Elo rating system is a method for calculating the relative skill levels of players in zero-sum games such as chess. It is named after its creator Arpad Elo, a Hungarian-American physics professor. The Elo system was invented as an improved ch ...

list from the matches played during the tournament. An initial rating is given to any new participant based on its rating in other chess engine rating lists.

Criteria for entering the competition

There is no definite criterion for entering into the competition, other than inviting the top participants under active development from various rating lists which can run on their Linux platform. Originally, TCEC used Windows instead of Linux. In addition, either

XBoard XBoard is a graphical user interface chessboard for chess engines under the X Window System. It is developed and maintained as free software by the GNU project. WinBoard is a port of XBoard to run natively on Microsoft Windows. Overview Original ...

or UCI protocol are required to participate. Usually chess engines that support

multiprocessor Multiprocessing is the use of two or more central processing units (CPUs) within a single computer system. The term also refers to the ability of a system to support more than one processor or the ability to allocate tasks between them. There ar ...

mode are preferred (8-cores or higher), and engines in active development are given preference. Since TCEC 12, engines like LCZero which use GPUs for neural processing were supported. Initially, the list of participants was personally chosen by Thoresen before the start of a season. His stated goal was to include "every major engine that is not a direct clone". In TCEC 13, DeusX was banned due to being a clone of Leela, and in TCEC 20, Houdini, Fire, Rybka (engine in Fritz up to TCEC 16), and Critter were banned due to allegations of plagiarism.

Tournament results

TCEC Seasons

:¹ Houdini has been disqualified since season 20 and its results in previous seasons have been nullified. :² Originally named "nTCEC Season 1". :³ Originally named "nTCEC Season 2". :⁴ Season 7 did not use endgame table bases at all and Stage two did not use opening books either.

TCEC Cups

TCEC Swiss

TCEC FRC (Fischer Random Chess)

TCEC DFRC (double Fischer Random Chess)

In DFRC, the start positions of the pieces are randomized independently for both players.

Other TCEC tournaments

:¹ Double round robin tournament.

References

Sources

Additional information for Season 4

Additional information for Season 5
* *
TCEC Season 12 report
by Guy Haworth and Nelson Hernandez
TCEC Season 13 report
by Guy Haworth and Nelson Hernandez * * * * * * * *

External links

TCEC Live Games Page
*
TCEC games archive
- Scroll down and click on Seasons.
chessdom.org
with an overview of TCEC's websites {{Chess, state=collapsed Computer chess competitions World championships in chess Recurring events established in 2010