Season 15 division 2 statistics

A summary statistics table of previous stages and seasons. 

Draw rate, wins


Final draw rate was 53.6%.


Game termination

The three most common game termination causes were:
38.4% - TCEC win rule
19.6% - SyzygyTB
19.6% - TCEC draw rule

Ginkgo crashed twice in the division, but it was reduced to 16 threads and survived.

Moves per game


Median= 61
Average= 72.7

There were 16 games longer than 100 moves, the longest was 244 moves (Game 85, AllieStein - Fritz, draw).

Time per game (hours)


Median= 1:05
Average= 1:04

Openings

There were 8-ply book openings in this stage chosen by Cato. The first letter of the ECO codes was distributed as follows:


The engines did not have a lot of freedom to choose the opening variant. 78.6% of the game pairs repeated the same ECO code twice, and 76.8% repeated the same opening variant. Only in 1.8% of the game pairs (one game pair) the ECO first letter was not repeated twice.

Reverse pairs, wins


Reverse pairs, same moves 

Pairs of reverse games diverged very quickly, 37.5% diverged immediately out of book, 73.2% of the pairs diverged at most after 1 move. There were many long sequences of repeated moves, the longest was 25 (!) plys (Ginkgo - rofChade, games 58 and 86, QGD Chigorin defense, Ginkgo won as white).

Season 15 division 2 results

Final crosstable

Xiphos and AllieStein promote to division 1. These two engines dominated division 2 and there was no doubt they would be the top 2. Xiphos won the division despite losing twice to AllieStein. AllieStein continues to improve and move up, still it lost two games to rofChade, blundering in a rook endgame in one of them.

Nirvana and Fritz are relegated to division 3. Nirvana was very weak in this division. The bottom half of the table was more competitive and the second engine to relegate wasn't determined until the last game. Ginkgo crashed twice and was in danger of being disqualified, but it managed to survive after it was reduced to 16 threads.

The engines to play in division 1 are: Andscacs, KomodoMCTS, Fizbo, Chiron, Laser, Jonny, Xiphos and AllieStein. The time control will be 60+5, twice as long as the lower divisions.

Action in the last RR

After RR3: Xiphos +11, AllieStein +8, Booot +2, ChessBrain and Ginkgo +0, Fritz -3, rofChade -5, Nirvana -13. The top is almost surely decided, Nirvana will be last. In the bottom rofChade still has a chance to overtake Fritz, and if Ginkgo crashes it will be disqualified. 

In rounds 22-23 Xiphos beat ChessBrain and increased the gap from third place to 5 points. Fritz survived against AllieStein in a long endgame, AllieStein's eval was over 14 but it couldn't convert. Ginkgo beat Fritz, Fritz is only 0.5 points away from the relegation zone.

5 rounds to go: Xiphos +12, AllieStein +8, Booot +2, Ginkgo +1, ChessBrain -1, Fritz -4, rofChade -5, Nirvana -13.

In rounds 24-25 AllieStein beat Ginkgo, Ginkgo is still one crash from disqualification. Xiphos beat Fritz and rofChade beat Booot, rofChade and Fritz change places and rofChade is in 6th place. Then Fritz beat Booot, Fritz and rofChade are tied.

3 rounds to go: Xiphos +13, AllieStein +9, Booot and Ginkgo +0, ChessBrain -1, Fritz and rofChade -4, Nirvana -13. Xiphos and AllieStein promote. The last game of the division will be rofChade - Fritz, it may determine which engine will finish in 7th place.

In round 26 rofChade and Fritz drew their games. AllieStein beat Xiphos and Ginkgo beat Booot without crashing. In round 27 rofChade drew AllieStein while Fritz lost to ChessBrain, so rofChade only needed a draw in the last game to avoid relegation while Fritz needed a win. Ginkgo beat Nirvana without crashing, Booot beat Xiphos. In the last round Ginkgo survived its last game without crashing, and rofChade held a draw against Fritz, so that Fritz is relegated together with Nirvana.