Sunday, August 2, 2020

Leela's Positional Masterclass in the Jerome Gambit


Yesterday's blog post was not very encouraging for either the Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) or the use of neural networks in chess analysis engines.

However, about a couple of weeks later, I received an email from Bob Derpson titled "Leela's Positional Masterclass in the Jerome Gambit"
I have recently stumbled upon your blog concerning the Jerome Gambit and have become very interested in the opening. 
While the gambit is often played as a means to for a tactically superior player to display the extent of their might against a weaker opponent, an aspect of the opening that is often forgotten is the severe hindrance in development that it poses to black. 
As a result, I believe traditional engine evaluations of the position to be inaccurate as they are not able to effectively gauge positional advantage due to their overvaluation of material. Likewise, humans will find it difficult to properly exploit black's positional disadvantage simply due to the way we have been trained to play chess. 
I decided to experiment with chess neural networks to discern whether or not the positional advantage for white in the Jerome can truly be translated into stone cold results.In doing so, I eventually stumbled on a truly fascinating game, held between Leela ID 62143 and Stockfish 1.0, with time controls of 1 second on each side plus 50 milliseconds increment.    
Let me say, right up front, that I have no idea how strong either of the chess engines are, or how they normally (i.e. not the Jerome Gambit) function at that time limit.

I do have to say, however, that Leela's play in the Jerome Gambit is jaw-dropping. My insights will be quite limited.

Leela ID 62143 - Stockfish 1.0
2020

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



4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Kf8 



Analyzed by Alonzo Wheeler Jerome in the July 1874 issue of the Dubuque Chess Journal, and played by him, successfully, in two correspondence games against Daniel Jaeger in 1880.

7.Qxe5 d6 8.Qf4+ Qf6 9.d3 



Fascinating. Leela is willing to allow the exchange of Queens, blunting its attacking chances and throwing its lot in with the two extra pawns, against the extra piece.

The Database points out that, previously, programs GNU Chess, DrunkenMaster 1.2, WB Nimzo 2000b, Zarkov 4.7 and Comet B48 played this way, with only the last one being successful. That was over a decade ago, however, when engines were much weaker, especially when it came to positional evaluations.

9...Bd7 

According to The Database, a new move, and equally interesting: Stockfish is not interested in the exchange, either.

10.Qg3 h5 11.h4 Ne7 12.c3 Qe6 13.Bg5 Qg4 



Now, Stockfish is willing to exchange. Perhaps it is influenced by its improved development.

14.Qh2 Bb6 15.Nd2 Bb5 



Komodo 10 prefers 15...a6 16.d4 Re8, which makes sense to me. Soon, it will struggle to understand, as well. 

16.f3 Qd7 17.c4 Ba4 18.b3 Bc6 19.O-O-O Ng6 



White's play reminds me of earlier times when humans would adopt "close" openings against computers, such as the Stonewall Opening, hoping to outplay them in slow strategic games, rather than tactical conflicts. As computer programs became more knowledgeable about positional play, this "anti-computer" strategy became less effective. Is Leela reintroducing the idea?

20.Nf1 Kg8 21.d4 Qf7 22.Ne3 Kh7 23.Kb2 a5 



24.c5 

A positional sacrifice.

24...dxc5 25.d5 Bb5 26.a4 Ba6 27.Rc1 



27...Rhe8 28.Rhd1 Ne5 29.Nc4 Nxc4+ 30.bxc4 



Black's King is safe, but his Bishops look like they are out of the game.

30...g6 31.e5 Qg7 32.Bf6 Qd7 33.Kb3 Qf7 



It is at this point that Komodo 10 (in blunder check mode) assesses Stockfish to have turned over the advantage to Leela. Unfortunately, it recommends 33...Qf5 34.Ka2 Rf8 which is beyond my comprehension

34.g4 hxg4 35.fxg4 Kg8 36.h5 Qh7 37.Qd2 gxh5 38.gxh5 Kf8 39.Rg1 c6 

Bob Derpson notes
Here, Leela's trademark ability to shut its opponent's pieces out of commission is displayed in its full glory, locking out both of black's bishops out of the game entirely, whilst simultaneously garnering a huge spatial advantage, dominating the center. 
Of course, it is impossible of human chess players of today to emulate such behavior. But, perhaps, one day in the future, in a world where neural networks have truly made their mark on chess and in the way players are conditioned to think about the game, where the Jerome Gambit can finally show its true potential.
Oh, and Komodo 10 points out that White has a checkmate in 16 moves, too.

40.Qf4 Re7 41.Bxe7+ Kxe7 42.Qf6+ Kd7 43.Rg7+ Qxg7 44.Qxg7+ Kc8 Black resigned


Very impressive!

Saturday, August 1, 2020

Jerome Gambit: The Future Is Here


Last month I received an email from Mitchell Jansen, who noted
I recently discovered your blog about the Jerome Gambit and I was surprised by the amount of research you have put into it. I was hoping that I could help add to that by submitting a game played by two of the top chess engines in circulation today. Hopefully, through careful analysis of this game, we will be able to understand better the intricacies of the Jerome Gambit in the Giuoco Piano.
The two chess engines in the game were Stockfish and Leela Chess Zero. I was not familar with the latter, so I sought an explanation from Wikipedia
 Leela Chess Zero (abbreviated as LCZero, lc0) is a free, open-source, and neural network-based chess engine and distributed computing project. Development has been spearheaded by programmer Gary Linscott, who is also a developer for the Stockfish chess engine. Leela Chess Zero was adapted from the Leela Zero Go engine, which in turn was based on Google's AlphaGo Zero project, also to verify the methods in the AlphaZero paper as applied to the game of chess. 
Like Leela Zero and AlphaGo Zero, Leela Chess Zero starts with no intrinsic chess-specific knowledge other than the basic rules of the game. Leela Chess Zero then learns how to play chess by reinforcement learning from repeated self-play, using a distributed computing network coordinated at the Leela Chess Zero website. 
As of 2020, Leela Chess Zero had played over 300 million games against itself, and is capable of play at a level that is comparable with Stockfish, the leading conventional chess program.
Interesting! Lc0 was listed as having an Elo rating of 3616, while Stockfish 11 was rated at 3604 - indeed, the highest rated Jerome Gambit game that I had ever heard of. I invited a third computer chess program, Komodo 10 (rated in the mere 3300s), along, and decided to take a look.

Lc0 - Stockfish 11
45 15 computer chess, 2020
Stockfish 11 was running on an Intel Core i7-8750H CPU at 2.20GHz with 16 GB of RAM while lc0 was running on an NVIDIA GeForce GTX 1070 GPU. 

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 



4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ke6



7.Qf5+ Kd6 8.f4 Kc6 

Defenders, take note.

9.Qxe5 Nf6 10.d4 

This is a typically aggressive Jerome Gambit move, that, superficially, blocks Black's dark-square Bishop, which is essential for White to castle. However, Komodo 10 was suspicious, preferring 10.d3, realizing that castling will not be possible, and resisting what danger might come down the e-file.

The Database has only 3 previous games with 10.d4, all wins by Black. This may be a result of 8...Kc6, which also only appears in those games.

10... d6 11.Qg5 

This is a new move, and, again, Komodo 10 disagrees - it is rated 300 points lower, of course it would disagree. It prefers 11.d5+ Kb6 12.Qc3 and a pursuit of the enemy King on the Queenside.

11...Bxd4 12.Qa5 Bc5 13.b4 Nxe4 



Stockfish willingly returns a piece, as White's Queen switch to the other side of the board leaves White' King at great risk.

14.bxc5 Qh4+ 15.g3 Nxg3 16.Be3 Nxh1+ 17.Kd2 Qxh2+ 18.Kc1 Ng3 

19.Nc3 Ne2+ 20.Kb2 Nxc3 21.Qxc3 d5 22.Rd1


White plays on, down a Rook. It no longer matters that Komodo 10 suggested 22.Rg1, instead.

22...Qe2 23.Qd4 Qc4 24.Qxg7 Qb4+ 25.Ka1 Re8 26.Qf6+ Re6


27.Qd8 Rxe3 28.Qxd5+ Kb5 29.Rb1 Re1 30.a4+ Ka6 31.Rxe1 Qxe1+ 32.Kb2 Qb4+ 33.Ka2 Qxa4+ 34.Kb2 Qb4+ 35.Ka1 Qxf4 36.Qd3+ 

If this were a human vs human game, I suppose this would be referred to as a "spite check".

36...Ka5 37.c4 Qc1+ 38.Ka2 Be6 39.c6 Bxc4+ 40.Qxc4 Qxc4+ 41.Kb2 Rd8 42.Ka3 Qc2 43.cxb7 Rd3 checkmate.



To quote Sean Connery's character in the movie "Zardoz", "I have seen the future, and it doesn't work."

Friday, July 31, 2020

Jerome Gambit: In This Case, Not So Much

The following game shows the dangers (for both sides) that the Jerome Gambit can provide, during blitz play. It is not possible to analyze deeply, and a slip can be fatal - providing the opposition notices. In this case, not so much.

Anonymous - Hai_no_Ken
10 5 blitz, lichess.org, 2020

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 




4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ng6 



7.Qd5+ Kf6 8.Qxc5 

Probably the "cleanest" response to Black's unusual King move. An alternative was 8.d4 (with the threat of 9.Bg5+, winning the Queen) Bb4+ 9.c3 Ke7 (to allow ...Nf6) 10.cxb4.

Also seen recently: 8.Qf5+ Ke7 9.Qxc5+ d6 10.Qg5+ Nf6 11.d4 h6 12.Qe3 Kf7 13.O-O Re8 14.f4 Rxe4 15.Qb3+ Be6 16.d5 Bxd5 17.Qh3 Kg8 18.Nc3 Be6 19.f5 Bd7 20.Nxe4 Nxe4 21.Qf3 Ng5 22.Qb3+ Kh7 23.fxg6+ Kxg6 24.Qd3+ Kh5 25.Bd2 a6 26.Rae1 Bb5 27.c4 Bc6 Black resigned, gabrielebattaglia - vgiagourta, lichess.org, 2020

8...d6 9.Qe3 N8e7 10.d4 h6 11.f4 Kf7 12.O-O Bg4


This was a blitz game, but the move illustrates the difference between development and just moving a piece.

13.f5 Ne5 

Simply giving a piece back. Perhaps he would have done better to force White to open up - and over-extend - his Kingside pawns with 13...Nf8 14.h3 Bg5 15.g4, but the first player would still be better.

14.dxe5 dxe5 15.Qb3+ Kf8 16.f6 



A classic Jerome Gambit move.

16...gxf6 17.Rxf6+ Ke8 18.Qb5+ c6 



19.Qxb7

It is hard to believe that one move could change the nature of the game, but this one does. Not only is White's Queen sidelined (at the price of a pawn) but the weakness of his first rank will quickly be exposed.

Hypothetically.

19...Rf8 

Instead, 19...Qd4+!? would have put Black on top, i.e. 20.Kf1 Rd8 21.Qb3 (21.Nc3 Bc8 22.Qb3 Ba6+) 21...Qd1+ (21...Bc8 22.Nd2 Ba6+ 23.c4) 22.Kf2 Qe2+ 23.Kg3 Rg8 and White would have to give up his Queen.

20.Rxf8+

Back on track. Black can now do some scary things, but he is only putting off his demise. 

21...Kxf8 21.Bxh6+ Ke8 22.Bg5 Qd1+ 23.Kf2 Qe2+ 24.Kg3 Ng6 



I know that the old saying is "three pieces and an attack" - but not in this case.

25.Qxa8+ Kf7 26.Qxa7+ Ke6 27.h3 Bh5 28.Qa8 Qxe4 29.Qe8+ Kf5 30.h4 Qg4+ 31.Kh2 Nxh4 



Dear White Knight and White Rook, I miss you. Signed, your King.

32.Qd7+ Kxg5 33.Qxg4+ Kxg4 34.Nc3 Bg6 35.Re1  White won on time in a clearly better position.





Thursday, July 30, 2020

Jerome Gambit: Early Joker


Not too long ago, François Crépault, a French Canadian chessplayer who has tried the Jerome Gambit, sent me three Jerome games played by Louis Morin.

I was quite excited. Playing mostly under the handle "MrJoker", largely blitz games at the Internet Chess Club (ICC), Morin has about 350 Jerome Gambit games in The Database. His communications, games and analysis show up in many places in this blog.

Still, one of the games M. Crépault sent me was one that I had never seen before - an over-the-board Jerome Gambit (he has played at least a half-dozen) in a serious tournament. I think it was his first.

The following game was played a couple of months before this blog began.

Morin, Louis - Piche, Justin
Montreal, Canada, 2008

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



4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ng6


7.Qd5+ Ke8 8.Qxc5 d6 9.Qe3 Nf6


10.d3 

Ten years later, Morin played 10.0-0 against Weston, a move that may be ever so slightly better, born of experience. In most lines of Jerome Gambit play, White will want to castle, while it is not clear if he will play d2-d3 or d2-d4; and if he wants to play f2-f4, that, too, is done more safely after 0-0.

10...Ng4 

It's never too early to harass White's Queen. The move is not a mistake, but more relevant would be 10...Kf7, planning to castle-by-hand. 

11.Qg5

White is rated significantly above his opponent, and so makes the choice Jerome Gambiteers sometimes do: simplify, and take the pawns against the piece, because in club/amateur games, that can be a lot easier to play.

11...Qxg5 12.Bxg5 h6 13.Bd2 Rf8 14.O-O


White doesn't have much, yet - in fact, Black has a small advantage - but his plan is simple: develop and advance the "Jerome pawns".

14...Nf4 15.Nc3 Be6 16.Rae1

Komodo 10 prefers 16.d4 Bc4 17.Rfd1 Ng6 18.f3 Ng6

16...Kd7 17.b3 

Preparing for d3-d4 without letting an enemy Bishop or Knight come to c4.

17...c5 18.Bxf4 Rxf4 19.Ne2 Rf6 20.h3 Ne5


I think I hear someone in the back seat of the car asking "Are we there yet?"

21.f4 Nc6 22.c3 b5 23.g4 

Aggressive, but 23.d4 cxd4 24.cxd4 might have been better. 

23...a5 

24.Ng3 g6 25.e5 dxe5 26.Ne4



A nice intermezzo move. Probably it is time for d3-d4 next move.

26...Rf7 27.Nxc5+ Ke7 28.Nxe6 Kxe6 29.d4 Raf8



30.Rd1

Letting the tension out of the position. White should have tried 30.c4 bxc4 31.bxc4 Kd7 32.d5 Nb4 33.Rxe5, when he would have 3 pawns for the piece.

30...exd4 31.cxd4 Kd5 32.f5 gxf5 33.Rf4 fxg4 34.Rxg4 Rf4 



35.Rg6 R8f6 36.Rg8 Rxd4 37.Rxd4+ Kxd4 38.Rg3 Rf5 39.Rg6 Rg5+ 40.Rxg5 White resigned

Not many strong players risk ratings and reputation to play the Jerome Gambit over-the-board. Hats off to Louis Morin.

Wednesday, July 29, 2020

Jerome Gambit: "Jerome Gambit Odds" and Ratings



I am involved in a game online, with a time limit of one day per move. My opponent is playing quite well, and it looks like we will draw.

I am rated about 500 points higher than he is, and although different systems calculate things differently, an online Win Probability Calculator suggests that I have a 96% chance of being successful. Interestingly enough, it also indicates that such a difference in ratings is equivalent to 4.16 pawns.

Oh, and I am playing the Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc4 4.Bxf7+) - giving him "Jerome Gambit odds".

Is that enough material sacrificed to compensate for the rating difference? Giving up two pieces (approximately 6 pawns) for 2 pawns in return would make us about even, and a draw would be a reasonable result.

How about that? 

I stumbled over an interesting comment that Grandmaster Larry Kaufman a dozen years ago on the Rybka Chess Community Forum. The discussion concerned an upcoming match between a strong computer chess program and a FIDE Master, with the computer giving Kight odds.
[T]he Elo equivalent of a given handicap degrades as you go down the scale. A knight seems to be worth around a thousand points when the "weak" player is around IM level, but it drops as you go down. For example, I'm about 2400 and I've played tons of knight odds games with students, and I would put the break-even point (for untimed but reasonably quick games) with me at around 1800, so maybe a 600 value at this level. An 1800 can probably give knight odds to a 1400, a 1400 to an 1100, an 1100 to a 900, etc. This is pretty obviously the way it must work, because the weaker the players are, the more likely the weaker one is to blunder a piece or more. When you get down to the level of the average 8 year old player, knight odds is just a slight edge, maybe 50 points or so.
So - according to GM Kaufman, the rating value of a Knight handicap may be 1,000 points between quite strong players, but it shrinks as the players' skill levels shrink. (If the Jerome Gambit is a blunder, or a way to give odds, it might be relevant to revisit Geoff Chandler's "Blunder table"). 

I think that means that if you're an average club player giving "Jerome Gambit odds", to somebody rated only a 100 points or so below you, you're out-performing expectations! 

Tuesday, July 28, 2020

Jerome Gambit: Is Black's King Actually Safer At d8?

?????

The following Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) revolves around the question: Is Black's King actually safer at d8? For a while, the surprising answer seems to be Yes, but quickly - this is a 1 0 bullet game - a resounding No takes its place.

angelcamina - traan
1 0 bullet, lichess.org, 2020

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 



4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ng6 



7.Qd5+ Kf8 8.Qxc5+ Qe7 9.Qe3 



Recently, White avoided the retreat, with two different outcomes:

9.Qxe7+ N8xe7 10.O-O Kf7 11.Nc3 Rf8 12.d3 Kg8 13.Bg5 Nc6 14.Nd5 d6 15.Nxc7 Rb8 16.Nd5 Nd4 17.c3 Nc6 18.f4 Bg4 19.d4 Be2 20.Rf2 Bc4 21.b3 Bxd5 22.exd5 Nce7 23.c4 Nf5 24.Re1 Nxd4 25.Be7 Nxe7 26.Rxe7 Nf5 27.Re6 Rbe8 28.Rxe8 Rxe8 29.g4 Re1+ 30.Rf1 Rxf1+ 31.Kxf1 Ne3+ 32.Ke2 Nxg4 33.b4 Nxh2 34.c5 dxc5 35.bxc5 Ng4 36.c6 bxc6 37.dxc6 Nf6 38.c7 Kf7 39.c8=Q Nh5 40.Qc7+ Kg6 41.Qxa7 Nxf4+ 42.Kd2 h5 43.Qa6+ Kg5 44.Qa5+ Kg4 45.a4 h4 46.Qa8 h3 47.Qh1 Kg3 48.a5 Ne6 49.a6 Nc7 50.a7 g5 51.Qb7 h2 52.Qxc7+ Kg2 53.a8=Q+ Kg1 54.Qc1+ Kf2 55.Qf8+ Kg3 56.Qfa3+ Kg2 57.Qc6+ Kg1 58.Qg3+ Kf1 59.Qcf3 checkmate, Anonymous - Beatboxer47, 3 3 blitz, lichess.org, 2020; and

9.Qxc7 Qxe4+ 10.Kf1 Nf4 11.Rg1 Qe2 checkmate, ianfencer - Evern, 1 0 bullet, lichess.org, 2020. 

9...Nf6 

Or 9...d6 10.O-O Nf6 11.d3 Kf7 12.Nc3 Rf8 13.f4 Kg8 14.b3 c6 15.Ba3 d5 16.Bxe7 Nxe7 17.e5 Ng4 18.Qg3 Nh6 19.d4 Nef5 20.Qd3 g6 21.h3 a6 22.g4 Ne7 23.Rae1 Be6 24.Na4 Kh8 25.Nc5 Bc8 26.f5 gxf5 27.gxf5 Bxf5 28.Rxf5 Nexf5 29.e6 Rg8+ 30.Kh2 Rg3 31.Qe2 Rag8 32.Qe5+ R3g7 33.Rg1 White won on time, angelcamina - albatronus, 1 0 bullet, lichess.org, 2020.

10.Nc3 

Or 10.d3 d5 11.O-O dxe4 12.dxe4 Qxe4 13.Qa3+ Qe7 14.b4 Be6 15.Re1 a5 16.c3 Kf7 17.Be3 axb4 18.Qb2 bxc3 19.Nxc3 Rhe8 20.Bg5 Qa3 21.Qd2 Rad8 22.Qc2 Bc4 23.Bxf6 gxf6 24.Ne4 Bd3 25.Qxc7+ Qe7 26.Qxe7+ Rxe7 27.Rad1 Red7 28.Nc5 Rd5 29.Nxb7 Ba6 30.Nxd8+ Black resigned, Atti0130 - smarlny, 5 0 blitz, lichess.org, 2020.

10...d6 11.O-O 

Alternately, 11.d4 Kf7 12.O-O Re8 13.f4 Nxe4 14.f5 Nf8 15.Nd5 Qd8 16.Qb3 Kg8 17.Nf6+ Black resigned, croc_master - Krog, 3 0 blitz, lichess.org, 2020. 

11...Ke8 

Black believes his King will be safer on d8. He plans to bring his Rook to e8 to pressure White's e-pawn.

12.d4 Kd8 13.f4 Re8 14.e5 dxe5 15.dxe5 



15...Ng4 16.Qg3 Qc5+ 17.Kh1 h5 



Black pushes his attack, even as his King sits on an open file.

18.h3 h4

Following the advice, If someone attacks one of your pieces, attack one of his, a more valuable one if possible

19.Qf3 Nh6 20.f5 

The "Jerome pawns" are on the march.

20...Nxf5 21.Qd3+ Bd7 22.Rxf5 c6 23.Rf7 Re7 24.Bg5 



Black's King is no longer safe.

24...Nxe5 25.Bxe7+ Qxe7 26.Rxe7 Nxd3 27.Rxd7+ Kxd7 28.cxd3 Kc7 

29.Rf1 Rd8 30.Rf7+ Kb6 31.Na4+ Kb5 32.b3 White won on time