Showing posts with label Derpson. Show all posts
Showing posts with label Derpson. Show all posts

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!