Season 13 division 3 statistics

Draw rate, wins



Final draw rate was 42.9%, relatively low.


Game termination

The three most common game termination causes were:
49.1% - TCEC win rule
21.4% - SyzygyTB
17.0% - TCEC draw rule

There were 3 crashes in the division, and two games had to be replayed due to a server connection problem.

Moves per game



Median= 57
Average= 66.5

There were 15 games longer than 100 moves, the longest was 176 moves (Leela - Ethereal, round 24, draw). 

Time per game (hours)



Median= 1:10
Average= 1:12

Openings

There were 2-move book openings in this stage chosen by Cato. Each opening was repeated 4 times in a round, and then again in the reverse games round. In total 14 2-move openings were used. The first letter of the ECO codes was distributed as follows:



If we use the opening 'family name' (using format FAMILY_NAME: VARIANT....) the top 3 are:
Sicillian - 23 times
Queen's pawn game - 9 times
English, Nimzovich-Larsen attack, Petrov - 8 times

The engines had a lot of freedom to choose the opening variant. However, 48.2% of the game pairs repeated the same ECO code twice, and 32.1% repeated the same opening variant. In 19.6% of the game pairs the ECO first letter was not repeated twice.

Reverse pairs, wins



Reverse pairs, same moves 


Pairs of reverse games diverged very quickly, 82.1% of the pairs diverged at most after 1 move. The longest repeated move sequence in a game pair was 14 plys long, in DeusX-Hannibal, rounds 7 and 14, both draws.

Season 13 division 3 final results

Division 3 final crosstable

 
Ethereal is promoted to division 2 and Bobcat is relegated to division 4. Places 2 and 7 in the table were decided by tiebreak. Arasan beat Leela in their head-to-head matches (one win in 4 games, 2.5-1.5) and it is the second engine to promote. Nemorino crashed twice while Hannibal crashed once, so Nemorino is the second engine relegated.

After RR3 the scores were Arasan +3, Leela +1, Pedone 0, DeusX 0, Hannibal -2, Nemorino -3. Leela's first game in RR4 against Hannibal ended in a Leela disconnect, this was later determined to be a server problem and the game had to be replayed. After 3 rounds were played and the crash result fixed the scores were Arasan +5, Leela +3, Pedone 0, DeusX -1, Nemorino -2, Hannibal -5. Leela and Arasan drew their game, two rounds to go the scores were Arasan +4, Leela +4, Pedone 0, DeusX 0, Nemorino -3, Hannibal -5. In round 27 Arasan lost to Pedone, Leela held a draw against DeusX, Hannibal and Nemorino also drew their game. The situation before the last round was Leela +4, Arasan +3, Nemorino -3, Hannibal -5. Pedone forced a perpetual check draw against Leela, then Arasan beat Bobcat equalizing points with Leela and reaching 2nd place. In the last two games Nemorino lost to Ethereal and Hannibal surprised DeusX, closing the gap in the last game.

Both neural network engines remain in division 3. There were several hardware issues, the GPU configuration was changed for division 3 and then changed again while division 3 was played. Connection problems caused games to crash and they had to be replayed. The many Leela fans were disappointed by the result, claiming that under good GPU conditions Leela would have promoted easily. Considering that Arasan got a point from a Nemorino crash in a lost position Leela fans have another reason to believe that Leela could have promoted. It is probable that in the next TCEC season the hardware will improve and Leela will continue to move up in the divisions.


Division 2 will start later today with the engines Gull, Texel, Xiphos, ChessBrainVB, Nirvana, Vajolet, Ethereal and Arasan. Time control will continue to be 30+10. After dominating division 3 Ethereal is trying to promote again, we will see if division 2 engines are tougher opponents.

Season 13 live blogging, Wednesday Aug 15th

Division 3 is in the 3rd RR out of 4. Ethereal is leading without loss and at least 3 points away from all the other engines. There are 3 engines in the race for second place. Pedone has 11 points, DeusX has 11 and one game less, and Arasan has 10.5 points. Leela with 9 points needs to win games to have a chance, so far it has only 2 wins in 19 games.

Currently the Nemorino - DeusX game is running, closing the 19th round.

move 15: It seems that DeusX went wrong very early in this opening. It did not follow the usual line in the Petrov opening, and Nemorino's eval was over 1.5 from move 6. DeusX lost a knight for a pawn on move 9, and Nemorino's eval was over 2 on move 14.

move 20: Evals are not moving, DeusX is trying to hold. Nemorino has a queen side passer and has a potential pawn attack on the king side since the engines castled in opposite directions.

move 25: The white knight is in a weak square, not trapped but doesn't have a good square to go to. DeusX is attacking the queen side, evals are increasing again.

move 30: After several pawn exchanges it seemed DeusX would give a rook for a bishop but it changed its mind. Nemorino's king ran to the king side, it is a knight and pawn up but its king side rook is stuck in the corner.

move 32: BOOM, evals over 5. DeusX seems to have missed some tactic, and it immediately realized it is losing. It seems the black king is under immediate threat and black is about to lose material.

move 37: Game over, adjudicated by the win rule. DeusX hasn't lost material yet but its king is under attack and only the queen is there to help. Both engines agreed black's position is hopeless.

With this loss DeusX remains 3rd 0.5 point behind Pedone and equal to Arasan. The race is going to be close to the end of the division.

Season 13 live blogging, Monday Aug 13th

Division 3 is getting close to the half way point. So far Ethereal is leading with a remarkable result of 8.5/10. Bobcat and Hannibal seem to be heading for relegation, and the remaining 5 engines - including the two NN engines Leela and DeusX - are in the struggle for the second promotion spot. Nemorino has had two early crashes and has been restricted to 16 threads, so far avoiding the 3rd strike and still playing well enough to have a chance of promotion. Pedone and Arasan are the remaining two engines in the race.

We will look at the Arasan-Ethereal game of round 11, Ethereal won the reverse game in round 4.

move 4: diverging from the reverse game right out of book, with a rare move e5. Arasan started optimistic with an eval around 0.5.

move 7: Ethereal eval dropped to 0 quickly. Arasan chose a rare opening line, Ethereal's eval turned slightly negative. Both the white knights are pinned.

move 10: The queen side is open, black has not developed the king side yet, delaying its castling plans. Ethereal gets a pawn, eval back to 0.

move 13: Ethereal with a very long think, but eval still 0. There is no castling in its PV, it created a pawn line across the board and it expects a lot of shuffling.

move 21: Evals are not moving, Ethereal is a pawn ahead, its king has not castled though it now can, Arasan has a bishop pair, both queens have been pushed back. Both engines seem to be playing defensively, unless there is some breakthrough I think the game will continue with a long shuffle and a draw.

move 24: Arasan is planning to trade bishops, another long think from Ethereal, again eval stays at 0.

move 33: All bishops are gone. Arasan got its pawn back and now its eval is also at 0. Perhaps the game will end at move 40 with the draw rule?

move 40: Ethereal's eval started to jump, reaching negative 0.6. Is the white back rank vulnerable? After queens are exchanged only RN vs RN left. Both evals are negative but not high, still drawish?

move 50: The queen side pawns are gone and evals are not going anywhere. Still looks like a draw, waiting for the engines to lower the eval so the game will be adjudicated.

move 60: The engines finally dropped their eval to 0. Is the end near? The 50-move counter is at 34.

move 69: Finally adjudicated by the draw rule. Arasan holds the reverse game, neither engine had a significant advantage in the game. Ethereal still unbeaten in the division, Arasan still strong in the promotion race.