TCEC S16 Starts; CCC9 Finishes

After a three week break from posting about the top two engine-to-engine competitions (see TCEC Not-so-Rapid Bonus; CCC9 Stage Two for the previous post), how hard will it be to catch up? To summarize that previous post:-

TCEC: The 'Rapid Bonus' is still running with Stockfish and Leela currently tied for first. • CCC: The 'Gauntlet Qualification' finished with Leela ahead of Stockfish by a significant margin. The next stage is the 'Gauntlet Quarterfinals'.

How did those events finish and what happened next?

TCEC: The 14-engine, six-round 'Rapid Bonus' (78 games per engine) finished with the following top scores:-

1) 55.5 Stockfish
2) 53.5 LCZero
3) 53.5 AllieStein
4) 48.0 Houdini

Over the next few weeks, the TCEC released two reports on its plans for the next season. The first was TCEC Season 16 – information and participants:-

TCEC Season 16 will feature a new format. It will keep the acclaimed Premier Division and Superfinal as in previous seasons, but will give more chances to starting engines to climb up the rankings. For this reason three leagues of 16 engines will be created. The event will start with a Qualification League where all newcomers will be featured, including new AB engines and Neural Networks. The top 6 of the Qualification League will promote to League 2 (also 6 will relegate), and the top 4 of League 2 will promote to League 1 (also 4 will relegate). Finally, the best placed 2 engines from League 1 will qualify for the Premier Division (also 2 will relegate).

The change of structure for TCEC is necessary due to the present rapid development of computer chess. With the new format more engines will have a chance to climb up the ranks and have a shot to enter in the elite.

The second report was TCEC S16 starts:-

Season 16 of the Top Chess Engine Championship starts this Sunday July 14th at 15:00 CEST. A total of 18 engines will battle for six promotion spots in the newly formed Qualification Division. Among them are three Neural Networks – ScorpioNN, ChessFighterNN, and Stoofvlees. [...]

Many engines are now hopping on the Neural Network bandwagon, making full use of GPUs. Yet, the champion Lc0 has released a strong version playing on CPU only! It is not a unique engine by the TCEC criteria, but it certainly is exciting to see it perform against real competitors of 3000 ELO+ strength. Thus, Lc0 CPU enters TCEC as a promo engine in the field. It will play all games in the division, but at the end of the division all results of the engine will nullified.

Between the end of the 'Rapid Bonus' and the start of the 'S16 Qualification Division', the TCEC ran a number of exhibition events.

CCC: After Leela won the 'CCC9 Gauntlet Qualification', the following events were held:-

CCC9 Gauntlet Quarterfinals (10 engines, 14 rounds)
1) 83.0 Lc0
2) 82.0 Stockfish
3) 76.0 Leelenstein
4) 74.5 Allie

CCC9 Gauntlet Semifinals (6 engines, 40 rounds)
1) 113.5 Stockfish
2) 112.5 Leelenstein
3) 110.5 Lc0

CCC9 Gauntlet Final (200 game match)
1) 103.5 Stockfish
2)   96.5 Leelenstein

Despite the close results, it's surprising to see that Leela did not qualify for the final match. I haven't found any Chess.com reports on the series of events, but I'll be patient before looking elsewhere for the reason(s). After the 'CCC9 Final', an exhibition match was organized:-

CCC9 Gauntlet Bonus (100 game match)
1) 53.5 Lc0
2) 46.5 Stockfish

The 'Gauntlet Bonus II', a 200 game match between the same two adversaries, is currently underway and is too close to call. After it finishes in a few days, we might see CCC10, for which plans are available.

Both the TCEC and the CCC have seen significant evolutions in their organization and documentation since I started weekly posts in January. Without their archives and other online aids, I would have been unable to produce this post. Kudos to both.

[For further information from the various stakeholders in the engine-to-engine events, see the tab 'TCEC/CCC Links' at the top of this page. • NB: Leela = LC0 = LCzero]