Komodo Dragon 2 released.

[KLc]

I see. Thanks for the explanation. I wasn’t really aware that things like that are difficult to figure out for MCTS.

[Chessqueen]

Here's a rather simple tactical position Dragon 2 in MCTS mode doesn't understand and I wonder what the problem is:

[d]8/pp3p2/5p2/5p1P/1P1bk3/P5B1/2K5/8 w - - 0 1

It wants to play 1.h6. But this move is bad because the first two pawns of the triple pawn group can move forward, thus opening the diagonal for the black bishop which then covers the queening square of the h-pawn, e.g. 1.h6 f4 2.Bf2 Be5 3.Bxa7 b5 4.h7 f5.

But white can easily promote the h-pawn by first sacrificing the bishop: 1.Bf4! Kxf4 2.h6 Ke3 3.h7 b6 4.h8=Q.

What's the problem here?

My settings are:

Code: Select all

Threads=2
Hash=1024
Use MCTS=true
MCTS Hash=1024
Ponder=false
OwnBook=false
Use Syzygy=false

Kurt you seems to be a strong player of at least Master strength, based on your analysis. Can you download Honey latest version and set it to play at your level, under Arena GUI you can click Engines ==> then Engine1, ==> configure ==> Engine level and select your level ( IM, Master, Expert etc) . It would be interesting to see a game to determine if the Levels for Honey are set up correctly to play against Human. To download it ==>https://github.com/MichaelB7/Stockfish/releases/tag/14

[pgn][Event "Computer chess game"]
[Site "MININT-UB2PIMJ"]
[Date "2021.07.09"]
[Round "?"]
[White "ChessQueen"]
[Black "Honey-v14-x86-64-bmi2"]
[Result "1/2-1/2"]
[BlackElo "2000"]
[ECO "D12"]
[Opening "Slav"]
[Time "18:05:06"]
[Variation "4.e3 Bf5 5.Nc3 e6 6.Nh4 Be4"]
[WhiteElo "Expert"]
[TimeControl "900+10"]
[Termination "adjudication"]
[PlyCount "104"]
[WhiteType "human"]
[BlackType "program"]

1. d4 d5 2. Nf3 Nf6 3. c4 c6 4. e3 Bf5 5. Nc3 e6 6. Nh4 Be4 7. f3 Bg6 8.
Bd2 Be7 9. cxd5 Nxd5 10. Nxg6 hxg6 11. g3 Nd7 12. e4 Nxc3 13. Bxc3 O-O 14.
Rc1 b5 15. b3 Qb6 16. Qd2 a5 17. h4 e5 18. h5 Rfd8 19. hxg6 fxg6 20. a4 Nf6
21. axb5 cxb5 22. d5 Ba3 23. Ra1 Rdc8 24. Bxb5 Rxc3 25. Qxc3 Bb4 26. Qxb4
Qe3+ 27. Be2 axb4 28. Rxa8+ Kf7 29. Kf1 Nh5 30. Rh3 Qxb3 31. Ra7+ Kf6 32.
Ra6+ Kf7 33. Ra1 Qc3 34. Rd1 Qc8 35. g4 b3 36. d6 Nf6 37. Bd3 Nd7 38. g5
Qc3 39. Rh1 b2 40. Kf2 Nc5 41. Be2 Ne6 42. d7 Qb3 43. Rd2 Qb6+ 44. Kg2 Ke7
45. Rb1 Qe3 46. d8=Q+ Nxd8 47. Rbxb2 Qxg5+ 48. Kf2 Qf4 49. Rd5 Qh2+ 50. Ke3
Qg1+ 51. Kd2 Qa7 52. Rbb5 Nc6[/pgn]

[Kooper]

Like Swordfish, this settings make Komodo Dragon 2.5.1
play less draw game against Lc0. It has creativity to
contempt undiscovered moves yet.

Dragon 2.5.1 tune1
[OPTIONS]
King Safety=103
Reduction=-15
Dynamism=90

[lkaufman]

Like Swordfish, this settings make Komodo Dragon 2.5.1
play less draw game against Lc0. It has creativity to
contempt undiscovered moves yet.

Dragon 2.5.1 tune1
[OPTIONS]
King Safety=103
Reduction=-15
Dynamism=90

Dynamism and King Safety only work with "Use Regular Eval". With the default NNUE, it just uses the net for eval and ignores these options. So all you are doing is slightly changing Reduction. It seems likely to me that a more negative Reduction value might help against Lc0 because there is less need for extreme depth against it, but we don't normally test against Lc0 so I don't have data on that point.