Season 9, stage 2 stats

Draw rate, wins

Final draw rate was 55%. There was a preference for white in the decisive games, 3 times more than black wins.

Game termination

The three most common game termination causes were:
40.8% - TCEC win rule
30% - TCEC draw rule
14.2% - TB position

There were 5 crashes, not a lot but too high for my liking for a second stage. The last one by Jonny shows that we may get more in stage 3.


Moves per game

Median= 64.5
Average= 70.61

The games were a bit longer than in stage 1, about 5 moves more.


Time per game (hours)

Median= 3:53
Average= 3:48

Despite having a few more moves the game duration was comparable to that of stage 1.


Openings

There were 8-move book openings in this stage chosen by Cato, so the engines had almost no say. The first letter of the ECO codes was distributed as follows:

A small bias for Sicillian openings. There was a similar graph in stage 3 of season 8.


If we use the opening 'family name' (using format FAMILY_NAME: VARIANT....) the top 3 are:
Sicillian - 58 times
English - 24 times
French - 20 times

The 8 predetermined moves usually made sure that the reverse pair games had the same opening definition. There were 7 cases where the full opening name was different, of these 3 had different ECO codes.

Reverse pairs, wins

Only 7/120 openings are suspect of a bias - each engine wins once, while 60/120 openings have a win+draw combination - a proof of engine strength, winning from one side and holding the other side. Cato is my hero.

Reverse pairs, same moves 

Most reverse pairs diverged within the first two moves. One game had the same move sequence for 17 plys (Protector - Chiron, 1/2-1/2).