zondag 11 augustus 2019

Opening selection TCEC 16 superfinal

Here are Jeroen Noomen's comments on the opening selection for the TCEC 16 superfinal:

"Here are the most important details regarding my selection of the openings for the TCEC 16 superfinal:

  • The selection of this set of 50 opening lines has been done in the period November-December 2018; it was finalized in December 2018 and hasn't been changed since then
  • All important openings will be played
  • The chosen lines typically have a length between 2 moves and 12 moves, with the exception of line #1, which is the starting position. This means the superfinal will start with two bookless games
  • Average move length is 7.26 (slightly higher than the 6.76 from the TCEC 15 superfinal)
  • There are sharp lines in the set, as well as positional linesmore complex lines, lines with opposite castling ("SALC", i.e. short and long castling), dubious lines and gambits
  • Some lines are borrowed from previous superfinals, they can be the same, somewhat shorter, or longer if necessary
  • The complexity of a position is one of my main selection criteria, i.e. most pieces are still on the board and there should be a lot of play left, with a reasonable chance for a decisive result
  • In 28 lines all 32 pieces are still on the board; in 18 lines there are still 30 or 31 pieces on the board; only in 4 lines there are less than 30 pieces left
  • In each line one side typically has an advantage, so each engine gets the chance to push for a win, while in the return game it has to defend the weaker side
  • I have avoided positions that could lead to many exchanges and/or have a high draw rate, as well as positions with symmetrical pawn structures and positions that could lead to easy wins for the side with an advantage. I also have avoided 'easy', very solid, classical positions, in which there is almost no chance to go wrong and where the expected draw rate will be very high (>90%)

ECO code distribution
ECO A: 11 lines
ECO B: 13 lines
ECO C: 12 lines
ECO D: 5 lines
ECO E: 9 lines

The reason there are less lines selected with ECO codes D and E, is because many lines in these sections are "too easy" for the current top programs and I consider them too drawish. Especially with a very long time control and with strong TCEC hardware.

Quick check
All lines have undergone a quick check with Stockfish, Komodo and Houdini, which means around 5 minutes on a Ryzen 1700X system (16 threads) for each engine on each position. The sole purpose of this quick check is to make sure: 

1) that there are no easy draws available (f.e. 0.00 scores and/or move repetitions)
2) that there will be no mass exchanges right after the book exit

Please note that the quick check cannot predict how the game will continue, or which engine 'likes' the position. The quick check is also not a tool to let engines pick opening lines. The only reason to do this quick check is to avoid quick draws right out of the opening.

A personal note
My sources to select openings for the TCEC superfinals are: GM games, correspondence games, databases, chess books, theoretical websites and my personal opening experience. I prefer lines that have a rather low draw rate in correspondence chess, i.e. preferably 50% or lower.

Personally I am a big fan of original, enterprising, lively, complex and non-standard play. In my opinion lines in this category can lead to far more interesting games than in the usual solid, classical stuff. Hence my opening selection reflects that preference.

Nevertheless, my picks will also always include well known opening lines, as long as they don't have a high chance of a draw. Please note that simple, classical, open and standard opening positions just have a very high chance of a draw, especially under TCEC superfinal conditions. We want to avoid >90% draws, therefore I exclude such lines from my selections. I understand that might not be to everybody's liking, but I'd say: if we have a lot of exciting games, this is the way to do it!

Finally: my expectations
The TCEC 15 superfinal saw 21 wins. This was slightly above my minimum goal of 20 wins. Of course I hope that in the TCEC 16 superfinal we will also reach at least this minimum of 20 wins. In any case, remember that in each line anything can happen! Wild lines can turn quickly into liquidations to a drawn ending, more quiet lines can suddenly explode into exciting games. While my selection method is destined to get as many games in the 2nd category, there is surely no guarantee this will happen.

Previous superfinals saw long strings of draws, but also lots of wins in a short period of time. This is normal in long matches between top engines and I am sure we will see this in the TCEC 16 superfinal, too.

So: have fun! I hope you enjoy the games and we will see lots of exciting chess and dramatic turn of events, like we had in all previous superfinals!"