Which move is better and why ?

[Dicaste]

I know this is a really silly question but since i started to improve my engine at openings i am trying to improve closed positions evaluation like KID or benoni so in this position Artista has no clue which move is better. Can someone analyze this position and can explain to me why it is better than other move.

Code: Select all

1. d4 c5 2. d5 Nf6 3. Nc3 d6 4. e4 g6 5. Nf3 Bg7 6. Be2 Bg4 7. O-O Bxf3 8. Bxf3
O-O 9. a4 Ne8 10. a5 *

Artista played itself until this position.

[d]rn1qnrk1/pp2ppbp/3p2p1/P1pP4/4P3/2N2B2/1PP2PPP/R1BQ1RK1 b - - 0 10

Artista switching those three moves whole the time. Na6, Nd7 and Nc7. I am not a good player (1850~ elo) for me i like Nd7 but i am not sure. Dear Lyudmil; i am expect a comment from you with your wisely explanations and others. Thanks.

[yanquis1972]

i will leave the brains to lyudmil, on a computer chess note the hiarcs book has Nd7 listed as the only move, & komodo prefers it as well after a fairly long search --


Analysis by Komodo 8 64-bit:

10...Nd7 11.Be2 Nc7 12.Be3 Qb8 13.Bg5 Re8 14.Qd2 a6 15.Be3 b5 16.axb6 Qxb6 17.Na4 Qb4 18.f3 Rab8 19.c3 Qb3 20.Ra3 Qb7 21.Rd1 Nb5 22.Raa1 Qc8 23.f4 Qc7 24.Bf3 Rf8 25.Rdb1 Nf6 26.Re1 c4 27.Qe2
+/= (0.68) Depth: 30 00:26:19 13824MN

[peter]

Hi John!

I looked for it in chessbase online database and found one white-won and one remis game.

Here is the .pgn with some SF- evals and alternative moves and your K8-variant.
At 10th black move in question I did let SF with full hash after some backward solving ponder in 2MV- mode and gave the output as annotation.

Code: Select all

[Event "CCC"]
[Site "?"]
[Date "2015.01.04"]
[Round "?"]
[White "Yavuz, E."]
[Black "Dalhelm, J."]
[Result "*"]
[ECO "A43"]
[Annotator "Stockfish"]
[PlyCount "109"]

1. d4 c5 2. d5 Nf6 3. Nc3 d6 4. e4 g6 5. Nf3 Bg7 6. Be2 Bg4 7. O-O Bxf3 8. Bxf3
O-O 9. a4 Ne8 10. a5 {Analysis by Stockfish 201214 64 POPCNT depth 37/52
2MV-mode    1. +/=  (0.69): 10...Nd7 11.Be2 Nc7 12.Bg5 Re8 13.Qd2 Qb8 14.Rfb1
Qc8 15.Be3 Rd8 16.Ra3 Re8 17.Nb5 Nxb5 18.Bxb5 a6 19.Be2 Qd8 20.Raa1 Qc7 21.f3
Rf8 22.c3 Rae8 23.Qc2 Qc8 24.Rd1 f5 25.f4 fxe4 26.Qxe4 Nf6 27.Qe6+ Qxe6 28.
dxe6 Ne4 29.g3     2. +/=  (0.70): 10...Nc7 11.Bg5 Nd7 12.Be2 Re8 13.Qd2 Qb8
14.Rfb1 Qc8 15.Be3 Rd8 16.Ra3 Re8 17.Rd1 Rb8 18.Ra4 a6 19.Ra2 b6 20.axb6 Rxb6
21.f3 Rf8 22.Re1 Re8 23.Rea1 Qb8 24.Rb1 Qc8 25.b3 Rb8 26.Nd1 Qb7 27.c3 Rbc8 28.
Bg5 Bf6} Nd7 11. Be2 (11. Qe1 {r4.ctg ?!} a6 {?!} (11... Nc7 {0.46/30})) 11...
Nc7 12. Be3 (12. Re1 a6 13. Bd3 e5 14. Qg4 f6 15. h4 Rf7 16. h5 c4 17. hxg6
hxg6 18. Bxc4 Nf8 19. Bd3 f5 20. Qg5 Bf6 21. Qg3 Bh4 22. Qh3 Bxf2+ 23. Kxf2
fxe4+ 24. Kg1 exd3 25. cxd3 Rh7 26. Qg3 Qh4 27. Qxh4 Rxh4 28. Re4 Rxe4 29. dxe4
Nd7 30. Bg5 Rc8 31. Kf2 Ne8 32. Ke3 Kf7 33. Ra4 Nef6 34. Rb4 Rc7 35. Na4 Ke8
36. b3 Nh7 37. Bh4 g5 38. Be1 Nhf6 39. Rc4 Kd8 40. Bb4 Ne8 41. Kd3 Ndf6 42. Nb6
g4 43. Bd2 Rxc4 44. bxc4 Nh5 45. Bg5+ Kc7 46. Ke3 Nef6 47. Bh4 Nd7 48. Nxd7
Kxd7 49. Kf2 Ke8 50. Bg5 Kf7 51. Bd8 Ke8 52. Bb6 Nf6 53. Kg3 Kf7 54. Kh4 Kg6
55. Bc7 Nxe4 56. Kxg4 Nd2 57. c5 dxc5 58. d6 Ne4 59. Kf3 Nf6 60. Bd8 c4 61. g4
Nd7 62. Ke4 Nc5+ 63. Ke3 c3 64. Bb6 Nd7 65. Bd8 e4 66. Bh4 Ne5 67. Bg3 Nd3 68.
Be1 Nxe1 69. d7 c2 70. Kd2 Nd3 71. Kxc2 Nb4+ 72. Kd2 Nc6 73. Ke3 Kf6 74. Kxe4
Ke6 {0-1 (74) Shalimov,V-Kosikov,A (2420) Soviet Union 1986}) (12. Bg5 {0.66/30
}) 12... Rb8 (12... Qb8 {John Dalhelm's K8-output-variant} 13. Bg5 Re8 14. Qd2
a6 15. Be3 b5 16. axb6 Qxb6 17. Na4 Qb4 18. f3 Rab8 19. c3 Qb3 20. Ra3 Qb7 21.
Rd1 Nb5 22. Raa1 Qc8 23. f4 Qc7 24. Bf3 Rf8 25. Rdb1 Nf6 26. Re1 c4 27. Qe2 {
K8-output's end} Nd7 {0.66/31}) (12... b6 {0.51/31}) 13. Qd2 b5 (13... f5 {0.
68/30}) 14. axb6 axb6 (14... Rxb6 15. b3 a6 {0.68/33}) 15. Rfb1 (15. Nb5 {0.92/
33}) 15... Ra8 16. Qc1 Nf6 17. f3 Qd7 18. Rxa8 Rxa8 19. Ra1 Qe8 20. Bf2 Qb8 21.
Nb5 Nfe8 22. c3 Nxb5 23. Bxb5 Nf6 24. Bc6 Ra7 25. Qf1 Nd7 26. Ra6 Ne5 27. Qa1
Rxa6 28. Qxa6 g5 29. Kf1 Bf6 30. Ke2 Qc7 31. Qa8+ Kg7 32. Kd2 h5 33. Kc2 h4 34.
h3 e6 35. Be3 Ng6 36. Bb5 Qe7 37. dxe6 fxe6 38. Qb8 Qd8 39. Qb7+ Kh6 40. Bc4
Nf8 41. Qf7 Qe7 42. Qxe7 Bxe7 43. Kb3 Kg7 44. Ka4 Kf6 45. Kb5 Ke5 46. Kxb6 d5
47. Bb5 d4 48. cxd4+ cxd4 49. Bd2 Ng6 50. Kc6 Nf4 51. Bf1 Nh5 52. b4 Ng3 53.
Bc4 Nh1 54. b5 Nf2 55. b6 {1-0 (55) Leiva Rodriguez,J (2424)-Lozano,N (2110)
Bogota 2013} *

I guess White is already a little better at 10th, SF's evals don't seem so bad to me, but as always have to be relativised over some moves in depth and width of the main variants interactively.


As for my personal pov, having looked not really deep into the variants and not beeing a KID- expert, I'd say 10...Nd7 and ...Nc7 might be equal probably transposing to each other sooner or later

[peter]

And about 10...Na6, which K8 considers too for some time after backward solving , I here have a game between SF and K8, 240'+30", 12 threads and 8G hash each, ponder on:

1. d4 c5 2. d5 Nf6 3. Nc3 d6 4. e4 g6 5. Nf3 Bg7 6. Be2 Bg4 7. O-O Bxf3 8. Bxf3 O-O 9. a4 Ne8 10. a5 Na6

11. Be2 Nec7 12. Bg5 Qd7 13. f4 b5 14. axb6 axb6 15. Bg4 Qd8 16. f5 b5 17. Qe1 Ne8 18. fxg6 hxg6 19. Qh4 Nf6 20. e5 dxe5 21. Rxf6 exf6 22. Ne4 fxg5 23. Nxg5 Qxg5 24. Qxg5 e4 25. h4 Bxb2 26. Rd1 Bd4+ 27. Rxd4 cxd4 28. h5 Kh7 29. hxg6+ fxg6 30. Qe7+ Kh6 31. Qxe4 Nc5 32. Qxd4 Nb7 33. Qb4 Rad8 34. Qxb5 Nd6 35. Qd3

Stockfish as White seems to make the full point rather convincingly

[BeyondCritics]

In this position Nb8-a6 seems bad on general grounds and Nd7 and Ne8-a6 are nearly equal positionally. Other options seem clearly worse. In any case black faces a difficult defense: No space, limited center control and no counterplay in sight.

Btw i personally don't think it is a good test position. If black plays Nd7 then white is better. If black plays Ne8-c7 white is better too, so what?
Give this test position to different engines. One engine will choose Nd7 and another engine will choose Ne8-c7. What did you learn? Not much.
In a good position the engines faces difficult, pivotal choices, which are uncorrelated. Something like a pawn sacrifice or so. You will then extract maximum information.
Just my 2 cent.

[Ferdy]

I know this is a really silly question but since i started to improve my engine at openings i am trying to improve closed positions evaluation like KID or benoni so in this position Artista has no clue which move is better. Can someone analyze this position and can explain to me why it is better than other move.

Code: Select all

1. d4 c5 2. d5 Nf6 3. Nc3 d6 4. e4 g6 5. Nf3 Bg7 6. Be2 Bg4 7. O-O Bxf3 8. Bxf3
O-O 9. a4 Ne8 10. a5 *

Artista played itself until this position.

[d]rn1qnrk1/pp2ppbp/3p2p1/P1pP4/4P3/2N2B2/1PP2PPP/R1BQ1RK1 b - - 0 10

Artista switching those three moves whole the time. Na6, Nd7 and Nc7. I am not a good player (1850~ elo) for me i like Nd7 but i am not sure. Dear Lyudmil; i am expect a comment from you with your wisely explanations and others. Thanks.

I think your engine is doing fine, those moves are good candidates.
A. Na6 with the idea of Nb4, a partial outpost.
B. Nc7 is to pressure d5 by playing e6. This also supports b5 break but you need to watch axb6, so Nd7 is required.
C. Nd7 has threat of Ne5 threatening to exchange at Bf3. Also b6 is now possible because the rook in A8 and queen in D8 are now connected. It is important to exchange that white's a5 pawn. Have a look on your pawn weakness (backward b7) and knight outpost eval.

[peter]

In this position Nb8-a6 seems bad on general grounds and Nd7 and Ne8-a6 are nearly equal positionally. Other options seem clearly worse. In any case black faces a difficult defense: No space, limited center control and no counterplay in sight.

Btw i personally don't think it is a good test position. If black plays Nd7 then white is better. If black plays Ne8-c7 white is better too, so what?
Give this test position to different engines. One engine will choose Nd7 and another engine will choose Ne8-c7. What did you learn? Not much.
In a good position the engines faces difficult, pivotal choices, which are uncorrelated. Something like a pawn sacrifice or so. You will then extract maximum information.
Just my 2 cent.

I agree that Na6 isn't quite as good as Nd7 and Nc7, but it isn't easily to be shown, and as for test positions I don't think we should look at the ones with clear single best moves only anymore.

Of course you get more information about the engine's search for these bms or ams by these classical test positions, but if you want to test the engines's evals for moves not as clearly to be discriminated you need to judge these evals compared to each other in "quiet" "positional" positions too.

Here is the latest SF dev. with empty hash on 4MV mode, depth 34:


rn1qnrk1/pp2ppbp/3p2p1/P1pP4/4P3/2N2B2/1PP2PPP/R1BQ1RK1 b - - 0 1

Analysis by Stockfish 030115 64 POPCNT:

1. +/= (0.65): 10...Nc7 11.Be2 Nba6 12.Bc4 Nb8 13.Bg5 Nd7 14.Be2 Rb8 15.Qd2 Qe8 16.Rfe1 Qd8 17.h3 Re8 18.Be3 Rf8 19.Ra3 Be5 20.Ra2 Nf6 21.Bh6 Re8 22.Bc4 a6 23.Na4 Nd7 24.Be3 Nb5 25.c3 Bg7 26.Raa1 Qc7 27.f4

2. +/= (0.66): 10...Nd7 11.Be2 Nc7 12.Bg5 Rb8 13.Qd2 Qe8 14.Rfe1 Qd8 15.h3 Bd4 16.Reb1 Nf6 17.Bd3 Be5 18.Re1 Nd7 19.f4 Bd4+ 20.Kh1 Re8 21.Bh4 Qc8 22.Rab1 b5 23.axb6 Rxb6 24.b3 Rb4 25.Rbd1 Bf6 26.Bg3 e5 27.Ra1 exf4

3. +/= (0.67): 10...Na6 11.Bg5 Nec7 12.Re1 Nb8 13.Be2 Nd7 14.Qd2 Bd4 15.Rf1 Re8 16.Kh1 a6 17.f3 Rb8 18.Rfb1 Bf6 19.Be3 Be5 20.Rf1 Bf6 21.Rfd1 b5 22.axb6 Rxb6 23.Ra2 Bg7 24.Kg1 Qc8 25.Na4 Rb8 26.Rda1 Bd4 27.Nc3 Bxe3+ 28.Qxe3 Qb7 29.b3

4. +/- (0.72): 10...a6 11.Be2


And here is a variant SF with Black played against K8 on 240'+30", 12 threads and 8G hash each, ponder on after


1. d4 c5 2. d5 Nf6 3. Nc3 d6 4. e4 g6 5. Nf3 Bg7 6. Be2 Bg4 7. O-O Bxf3 8. Bxf3 O-O 9. a4 Ne8 10. a5 Nd7 11. Be2 Nc7 12. Be3
12...b6

which was the first SF-deviation at backward solving from Leiva Rodriguez-Lozano, Bogota 2013, quoted in .pgn of my first posting.


1. d4 c5 2. d5 Nf6 3. Nc3 d6 4. e4 g6 5. Nf3 Bg7 6. Be2 Bg4 7. O-O Bxf3 8. Bxf3 O-O 9. a4 Ne8 10. a5 Nd7 11. Be2 Nc7 12. Be3 b6 13. axb6 Nxb6 14. Qd3 Qd7 15. h4 f5 16. Bc1 a5 17. h5 gxh5 18. Bxh5 fxe4 19. Nxe4 Qf5 20. Bf3 Ncxd5 21. Qd1 Be5 22. Ra3 Kh8 23. Ng5 Bf4 24. Bxf4 Nxf4 25. Bxa8 Qxg5 26. Rg3 Qf6 27. Bf3 a4 28. Qa1 Nc4 29. b3 axb3 30. Qxf6+ Rxf6

Compared to the variant in my second posting of K8 playing with Black after 10...Na6 against SF,

1. d4 c5 2. d5 Nf6 3. Nc3 d6 4. e4 g6 5. Nf3 Bg7 6. Be2 Bg4 7. O-O Bxf3 8. Bxf3 O-O 9. a4 Ne8 10. a5 Na6

11. Be2 Nec7 12. Bg5 Qd7 13. f4 b5 14. axb6 axb6 15. Bg4 Qd8 16. f5 b5 17. Qe1 Ne8 18. fxg6 hxg6 19. Qh4 Nf6 20. e5 dxe5 21. Rxf6 exf6 22. Ne4 fxg5 23. Nxg5 Qxg5 24. Qxg5 e4 25. h4 Bxb2 26. Rd1 Bd4+ 27. Rxd4 cxd4 28. h5 Kh7 29. hxg6+ fxg6 30. Qe7+ Kh6 31. Qxe4 Nc5 32. Qxd4 Nb7 33. Qb4 Rad8 34. Qxb5 Nd6 35. Qd3

there is much less dynamics in the first one variant than in the second one, and to relativate the engines' evals over the moves of the one and the other one variant at forward and at backward solving yet shows some more difference than there is in comparing the ones of MV at the starting position.


It's a good test position as for my pov to judge evals together with search (Can you really discriminate those two of them at all at positional testing?
If you want to, you'll have to have quite certain kinds of test positions for sure.) in an opening- position of some dynamics but several less forced lines with eval- progressings of small differences

[Dicaste]

Thanks for those analysis people. I know this is not a good test position as i said it's little bit silly however but Artista showed +0.43 for white both of Nc7 and Nd7. Na6 is +0.40. When score not changed after deep searching i wanted to ask this question. Stockfish evaluated differently those moves. Thanks for analyze again. I'm just keeping those positions and analysis collect them and preparing for updates. Thanks again.