Friday, June 9, 2017

Jerome Gambit: Slicing the Silicon

Here we have another human - computer battle, where the silicon beast can not make sense out of the Jerome Gambit, even as human observers might not be able to make sense out of some of the computer's moves.

Wall, Bill - Computer-level 6
Chess.com, 2017

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+




4...Kxf7 5.Nxe5+ Kf8 6.O-O



This move really got me thinking. Bill has played it before, but it is arguably not the "objectively best" move, so I have to wonder what he had in mind. He could have been avoiding "book" lines. He could have been forcing the computer to "think" on its own - and we will see that it doesn't do a masterly job of that.

6...Qf6

Instead, 6...Nxe5 was seen in billwall - DeDrijver, Chess.com, 2012 (1-0, 20) while 6...d6 was seen in Wall,B - Anonymous, lichess.org, 2016 (1-0, 26) and Wall,B - Guest399227, PlayChess.com, 2016 (1-0, 17)

7.Nxc6 Qxc6

Preserving the pawn structure, which did not happen (not that it mattered much) in Wall,B - NN, lichess.org, 2016: 7...dxc6 8. Nc3 Bd6 9. d4 h6 10. e5 Bxe5 11. dxe5 Qxe5 12. Re1 Qg5 13. Bxg5 Black resigned.

8.d4 Bb6 9.Nc3 d6 10.Bg5




The Bishop often goes here to attack a Knight at f6. But why wait?

10...Qe8 11.f4 Qg6

Here we see an interesting reversal of roles: usually in the Jerome Gambit it is White's Queen that moves repeatedly.

12.h4

Bill suggests he could have advanced the other Rook pawn as well.

12...Qe8 13.f5 Ba5


14.f6 gxf6

Stockfish 8 suggests 14...Bxc3 first, leading to an even game.

15.Qf3 Qf7 16.Nd5 h5



This does not look like the strongest defense. It is hard to see what it accomplishes.

17.Bxf6 Nxf6 18.Nxf6 Be6 19.Qg3 Ke7 



Escaping the deadly f-file, although material will be lost.

20.Nd5+ Bxd5 21.Rxf7+ Bxf7 22.Qg5+ Kd7 23.Qxa5 b6 



White has a Queen and a pawn for a Rook and a Bishop.

24.Qb5+ c6 25.Qf5+ Be6 26.Qf6 Rh7



Shouldn't a Rook have gone to f8 instead?

27.d5 cxd5 28.exd5 Bg4 29.Re1 Rg8 30.Re3 Rc8 31.a4 Rc7 
32.a5 bxa5 33.Re6 Rc5

Black's pieces cannot coordinate. Note, if 33...Bxe6 then 34.Qxe6+ Kd8 35.Qg8+ and a Rook will fall.

34.Rxd6+ Kc7 35.Rc6+ Rxc6 36.Qxc6+ Kd8 37.d6 a4



A human might resign here.

38.Qa8+ Bc8 39.c4 Rb7 40.c5 Rg7 41.Qf3 Rg6 42.Qf7 Re6 43.c6 Ba6 44.Qd7 checkmate



Wednesday, June 7, 2017

Facing the Jerome Gambit: Artificial Non-Intelligence

Programmers who create chess-playing engines usually try to make them as strong as possible. They then develop ways to scale back the strength, creating levels of play that can give a human opponent a chance to have a decent game. How, then, to make a smart computer program weaker? This question comes up a few times in the following game, as Bill wall takes on a program at a playable level.

Wall, Bill - GarboChess JS 6.0
2017

1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. Bxf7+



4...Kxf7 5.Nxe5+ Nxe5 6.d4 Qh4


This move is likely "book" for the program.

7.O-O

There are 150 games with this position in The Database.

7...Bb4

The computer saves an endangered piece, but the move is hardly consistent with the counterattacking ideas of the line. It is not surprising that this is the only game in The Database with the move.

8.dxe5 Qxe4 9.a3 Bc5

Keeping the Bishop on an active square, but the program "overlooks" a tactic. The safer move was 9...Be7 with Black still better.

10.e6+ dxe6 11.Qh5+ g6

Kicking the enemy Queen with the pawn is all-too-human an idea; better was probably 11...Qg6. Black has frittered away its advantage with the last three moves.

12.Qxc5 c6 13.Nc3 Qxc2



Pawn-grabbing is a known failing of early and weaker chess programs. Lack of development and King safety are more important issues.

14.Re1 Nf6 15.Bg5 Nd5 16.Qd4 Bd7



17.Nxd5 cxd5 18.Qf6+ Kg8 19.Bh6 Qxb2 

Putting off checkmate for a very short time.

20.Qxb2 Kf7 21.Qg7+ Ke8 22.Bg5 Rf8 23.Qe7 checkmate



Monday, June 5, 2017

Jerome Gambit: The Queen Goes Where She Will

One thing that seems to give defenders a sense of ease is the number of times White's Queen moves in the Jerome Gambit. It is important that such a feeling be translated into further strong moves, not inattention or overconfidence. View the following game.

Wall, Bill - PerGranBom
lichess.org, 2017

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+




4...Kxf7 5.Nxe5+ Nxe5 6.d4 Bxd4 7.Qxd4 Nc6

An interesting alternative to the more usual 7...d6 (although the game transposes).

8.Qd1



Bill has moved the Queen to different squares in other games:

8.Qd2 d6 9.Nc3 Be6 10.O-O g6 11.f4 Nge7 12.Nd5 Bxd5 13.exd5 Nb8 14.f5 gxf5 15.Qe2 Qd7 16.Bh6 Ke8 17.Rae1 Rg8 18.Rxf5 Kd8 19.Rf7 Re8 20.Bg5 c6 21.Qh5 cxd5 22.Rfxe7 Rxe7 23.Rxe7 Qb5 24.Qf7 Nd7 25.Rxd7+ Kc8 26.Rd8 checkmate, Wall,B - 1063314, lichess.org, 2017;

8.Qd5+ Kf8 9.Nc3 Nf6 10.Qc4 d6 11.O-O Ne5 12.Qb3 c6 13.f4 Nf7 14.Be3 Qe7 15.Rae1 Be6 16.Qb4 a5 17.Qd4 Ng4 18.Bc1 c5 19.Qd3 h5 20.h3 Ngh6 21.f5 Bd7 22.Nd5 Qd8 23.f6 g6 24.Ne7 Ne5 25.Qxd6 Nhf7 26.Qxc5 b6 27.Qd5 Be8 28.Bf4 Qxd5 29.exd5 Bb5 30.Rf2 Nd7 31.Nxg6+ Kg8 32.Nxh8 Kxh8 33.Re7 Kg8 34.Be3 Rc8 35.b3 Nde5 36.Bxb6 Black resigned, Wall,B - Guest7503555, PlayChess.com, 2017;

8.Qd3 Nf6 9.Nc3 d6 10.O-O h6 11.f4 Re8 12.Bd2 Kg8 13.Rae1 a6 14.Nd5 Be6 15.Bc3 Bxd5 16.exd5 Nb8 17.Bxf6 gxf6 18.Qg6+ Kf8 19.Qxh6+ Kg8 20.Qg6+ Kf8 21.Re5 dxe5 22.fxe5 Nd7 23.exf6 Black resigned, Wall,B - Number555777, lichess.org, 2017; and

8.Qc4+ Ke8 (8...Kf8 9.O-O Qf6 10.Nc3 Qd4 11.Qe2 Nge7 12.Nb5 Qb6 13.Be3 Qa5 14.c4 a6 15.Bd2 Qb6 16.Qf3+ Kg8 17.Qb3 axb5 18.c5+ Black resigned, Wall,B - Guest526975, PlayChess.com, 2016) 9.O-O d6 10.Nc3 Qe7 11.Re1 Ne5 12.Qd4 c5 13.Qd2 Nf6 14.f4 Nc4 15.Qe2 Be6 16.e5 Bg4 17.Qxc4 Black resigned, Wall,B - Kas55, lichess.org, 2016

8...Nf6 9.Nc3 d6 10. O-O Re8 11.Bf4



Black is doing well, but he is tempted by the "free" e-pawn. The discovered attack on White's Queen that evolves turns out to be harmless.

11...Nxe4 12.Qd5+ 

On revient toujours a son premier amour.

12...Be6 13.Qxe4 g6 14.Rae1 Bxa2 15.Qxe8+ Qxe8 16.Rxe8 Rxe8 17.Nxa2


This was not what Black had envisioned. Now he is the one with a pawn for a piece.

17...Nd4 18.Be3 Nxc2 19.Rc1 Nxe3 20.Rxc7+ Re7 21.Rxe7+ Kxe7 22.fxe3 d5 23.Nc3 Kd6 24.Nb5+ Black resigned