Wednesday, March 15, 2023

Jerome Gambit: Arena (Part 5)



Here are a couple of  3 0 blitz games from the third place finisher in the 2021 Jerome Gambit Arena at lichess.org.


GLORIARODRIGUEZ_UNE - onderch01

3 0 blitz, Jerome Gambit Arena, lichess.org, 2021

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.d3 Be7 7.d4 Ng6 8.Qh5 (or 8.Nc3 or 8.f4) 8...d6 9.e5 (or 9.Nc3 or 9.f4) 9...dxe5 10.dxe5 Qd5 11.O-O Qxe5 12.Qxe5 Nxe5 (White is down two pieces for a pawn, with the Queens off of the board) 13.Re1 Ng6 14.Re3 Nf6 15.Nc3 b6 16.Rf3 Bb7 17.Re3 Bc5 18.Rf3 Bxf3 19.gxf3 Nf4 20.Bxf4 Rhe8 21.Na4 Bd6 22.Bxd6 cxd6 23.Nc3 Rac8 24.Kf1 a6 25.Ne4 Rxc2 26.Nxf6 gxf6 27.Kg2 Ree2 28.Rg1 Rxf2+ 29. Kh1 Rxh2 checkmate


onderch01 - KAPANN

3 0 blitz, Jerome Gambit Arena, lichess.org, 2021

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ng6 7.Qxc5 d6 8.Qe3 Nf6 9.Qf3 (9.d3Bg4 10.Qb3+ Be6 11.Qxb7 Rb8 12.Qxa7 Nxe4 13.O-O h5 14.d3 Nf6 15.Bg5 h4 16.h3 Rh5 17.Bxf6 gxf6 18.Nc3 Ra8 19.Qe3 Rg5 20.Ne4 Rh5 (a bit better was 20...Rf5) 21.Qf3 (21.g4 Rh8 22.f4 Bd5 23.f5) 21...f5 (lets the Rook hang; better 21...Rf5) 22.Nxd6+ (the simple 22.Qxh5) 22...cxd6 (22...Qxd6 23.Qxh5 Rh8 24.Qf3 Nf4 is even) 23.Qxh5 Qb6 24.b3 Rh8 Black resigned


Tuesday, March 14, 2023

Jerome Gambit: Arena (Part 4)



The second place finisher in the 2021 Jerome Gambit Arena at lichess.org played some interesting 3 0 blitz games.


GlobalChess_Twitch - sametneni

3 0 blitz, Jerome Gambit Arena, lichess.org, 2021

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ g6 7.Qxe5 Bd6 (not a viable defense; better was 7...Qe7 or 7...d6) 8.Qxh8 Qe7 9.Qxh7+ Kf8 10.Qxe7+ Bxe7 (White is up 3 pawns and the exchange.) 11.Nc3 c5 12.d3 d6 13.h4 Bg4 14.f3 Bh5 15. g4 Bxg4 16.fxg4 g5 17.Bxg5 Bxg5 18.hxg5 Re8 19.Nd5 Re5 20.Kd2 Rxg5 21.Raf1+ Ke8 22. Rhg1 Kd7 23.Rf7+ Kc6 24.c4 Nh6 25.Rc7 checkmate


sey1t - GlobalChess_Twitch

3 0 blitz, Jerome Gambit Arena, lichess.org, 2021

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ke6 7.Qh3+ Ke7 8.Qh4+ (8.Qc3) Nf6 9.c3 d6 10.d4 Nd3+ 11.Kd2 Nxc1 12.dxc5 dxc5+ 13.Kxc1 Bg4 (better to step out of the pin with 13...Kf7) 14.f3 Bh5 15.Nd2 (15.e5) 15...Qd6 (unpin 15...Kf7) 16.Qg3 (last chance 16.e5) 16...Qxg3 17.hxg3 Bf7 18.Kc2 b6 19.Rae1 Rad8 20.f4 Ng4 21.Rd1 Ne3+ 22.Kc1 Nxd1 23.Rxd1 Rd7 24.b3 Rhd8 25.e5 Bg6 26.g4 Rd3 27.Kc2 Rg3+ (FYI 27...Rxd2+ 28.Kc1 Rc2+ 29. Kb1 Rxd1#) 28.Kb2 Rxg2 29.Kc1 Rd3 30.f5 Be8 31.Nb1 Rxd1+ 32.Kxd1 Bc6 33.b4 cxb4 34.cxb4 Rxg4 35.Nc3 Rxb4 White resigned


GlobalChess_Twitch - onderch01

3 0 blitz, Jerome Gambit Arena, lichess.org, 2021

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Kf8 7.Qxe5 d6 8.Qg3 Nf6 9.d3 Bd4 10.O-O h5 11.c3 Be5 (more consistent as 11...h4 12.Qf4 Bb6 or 11...b6) 12.f4 h4 13.Qf2 Ng4 14.Qe2 Bf6 15.h3 Nh6 16.e5 Be7 17.d4 Nf5 18.Qd3 Ng3 19.Rf2 c5 20.Nd2 Bf5 21.Qe3 cxd4 22.cxd4 dxe5 23.fxe5 g6 24.Nf3 Kg7 25.Bd2 Rc8 26.Bc3 Rf8 27.Rd1 Kh7 28.d5 Bc5 29.Bd4 Ne4 (29...Qxd5) 30.Re2 (30.Bxc5 Rxc5 31.Rd4 Nxf2 32.Rxh4+ Kg7 33.Qxc5 Ne4) 30...Be7 (last chance 30...Qxd5) 31.d6 Bxd6 32.exd6 Ng3 33.Ng5+ Kh6 34.Nf7+ Kh7 35.Qh6+ Kg8 36.Qg7 checkmate



Monday, March 13, 2023

Jerome Gambit: Arena (Part 3)



The winner of the 2021 Jerome Gambit Arena at lichess.org also played a trio of 3 0 blitz games that lasted a bit longer.


onderch01 - Cetin_Demirkol

3 0 blitz, Jerome Gambit Arena, 2021

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ke6 7.Qf5+ Kd6 8.c3 Nd3+ 9.Kd1 Nxf2+ 10.Kc2 Nxh1 11.Qd5+ Ke7 12.Qxc5+ d6 13.Qg5+ Nf6 14.Qxg7+ Ke6 15.d4 d5 16.Bg5 dxe4 17.Nd2 (17.d5+Nf2 (17...Rg8 was the move for advantage) 18.Rf1 (18.Bxf6 Qf8 19.Qxh8 Qxf6 20.Qe8+ Qe7 21.Qh5 equal game) 18...Rf8 (again 18...Rg8, i.e. 19.Bxf6 Rxg7 20.Bxd8 Rxg2 Black is better) 19.Rxf2 Qe7 20.d5+ Ke5 21.Bxf6+ (21.Qxe7+ Kxd5 22.c4+ Kc6 23.Rxf6+ Rxf6 24.Qxf6+ Be6 25.Qxe6+ Kc5 26.Be7+ Kd4 27.Qxe4#) 21...Qxf6 22.Nc4+ Kxd5 23.Rxf6 Rxf6 24.Qxf6 b5 25.Ne3+ Kc5 26.Qe5+ (26.b4# is quicker, but White has his own plan for winning) 27...Kb6 28.c4 Bd7 29.cxb5 Bxb5 30.Qd4+ c5 31.Qf6+ Ka5 32.b3 Bd3+ 33.Kd2 Kb4 34.Qc3+ Ka3 35.Qc1+ Kb4 36.a3+ Kxb3 37.Qc3+ Ka4 38.Qxc5 Rg8 39.Qb4 checkmate


Cetin_Demirkol - GLORIARODRIGUEZ_UNE

3 0 blitz, Jerome Gambit Arena,lichess.org, 2021

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ke7 (this error largely decides the game as White recovers his material and transitions to a pawn-up Queenless middlegame) 7.Qxe5+ Kf7 8.Qxc5 d6 9.Qh5+ g6 10.Qf3+ Qf6 11.Qxf6+ Nxf6 12.d3 d5 13.e5 Ng4 14.d4 b6 15.h3 Nh6 16.Bxh6 c5 17.c3 cxd4 18.cxd4 Bf5 19.Nc3 a6 20. O-O b5 21.Nxd5 Ke6 22.Ne3 Bd3 23.f4 Bxf1 24.d5+ Kd7 25.Kxf1 Rac8 26.Ke2 Ke7 27.Bg7 Rhg8 28.Bf6+ Kd7 29.e6+ Kd6 30.Be5+ Kc5 31.Rc1+ Kb6 32.Rxc8 Rxc8 33.d6 Rc2+ 34.Nxc2 b4 35.e7 Kc6 36.e8=Q+ Kb7 37.Qd7+ Kb6 38.Qc7+ Black resigned


GlobalChess_Twitch - Cetin_Demirkol

3 0 blitz, Jerome Gambit Arena, 2021

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ke6 7.c3 (White does not recover from this move) Nd3+ 8.Kd1 Nxf2+ 9.Kc2 Nxh1 10.d4 (10.Qxc5) 10...Bf8 11.Qf5+ Ke7 12.Na3 d6 13.Bg5+ Nf6 14.Qf3 Kf7 15.Rxh1 Be7 16.e5 Rf8 17.exf6 Bxf6 18.Qh5+ Kg8 19.Bd2 g6 20.Qd5+ Kg7 21.h4 c6 22.Qe4 Bf5 White resigned




Sunday, March 12, 2023

Jerome Gambit: Arena (Part 2)

 

The 2021 Jerome Gambit Arena event at lichess.org (see the previous post) included some very one-sided victories. Some players appear not to have been ready for the conflict.

UzunMehmetErdem - GLORIARODRIGUEZ_UNE
3 0 blitz, Jerome Gambit Arena, lichess.org, 2021
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 White resigned

Dolar3lira - Cetin_Demirkol
3 0 blitz, Jerome Gambit Arena, lichess.org, 2021
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 White resigned

GLORIARODRIGUEZ_UNE - sey1t
3 0 blitz, Jerome Gambit Arena, lichess.org, 2021
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Black resigned

Cetin_Demirkol - zfruzn
3 0 blitz, Jerome Gambit Arena, lichess.org, 2021
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ g6 7.Qxe5 d6 8.Qxh8 Nh6 9.Qxd8 Black resigned

KAPANN - sey1t
3 0 blitz, Jerome Gambit Arena, lichess.org, 2021
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ g6 7.Qxe5 d6 8.Qxh8 Nf6 9.Qxd8 Black resigned

Cetin_Demirkol - root129
3 0 blitz, Jerome Gambit Arena, lichess.org, 2021
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ g6 7.Qxe5 Bd6 8.Qxh8 Nf6 9.Qxd8 Black resigned

And then there was this wild affair

GLORIARODRIGUEZ_UNE - GlobalChess_Twitch
3 0 blitz, Jerome Gambit Arena, lichess.org, 2021
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ke6 7.f4 Ng6 8.f5+ (attractive, but 8.Qxc5 is stronger) Kf7 (cooperative, 8...Ke7 was stronger) 9.fxg6+ hxg6 10.Qxh8 Qf6 11.c3 (11.Rf1 would win the Queen) 11...d5 (instead, 11...Qf2+ 12.Kd1 Qxg2 is overwhelming) 12.d4 (or 12.Rf1) Bb6 13.exd5 (or 13.e5 or 13.Rf1) 13...Qe7+ 14.Kd1 Bg4+ 15.Kc2 Qe2+ 16.Nd2 Bf5+ 17.Kb3 Qb5+ 18.Ka3 Bc2 (18...Qa6+ 19.Kb3 Qb5+ 20.Ka3 a5) 19.Rf1+ Nf6 20.Qxa8 (White needs to get his Queen back into play while protecting his King, e.g. 20.Rxf6+ Kxf6 21.Qh4+ g5 22.Qf2+ Kg6 23.b3 Re8 24.Nc4 Bd3 25.Qg3 Bxc4 26.bxc4 Qxc4 27.Qxg5+ Kf7 28.Bd2 Qa6+ 29.Kb3 Bxd4 30.d6 Bf6 31.Qd5+ Kg6 32.dxc7 Qb6+ 33.Kc2 Qxc7 34.Re1 Rxe1 35.Bxe1 Qe7) 20...Qa5 checkmate


Saturday, March 11, 2023

Jerome Gambit: Arena (Part 1)



I recently came across a report on the internet site lichess.org, of a 2021 Jerome Gambit Arena event.

Here is a table with the results.

The games will come next.


Jerome Gambit Arena  2021         rating         score

  1. Cetin_Demirkol                         2138           5.0/6

  2. GlobalChess_Twitch                  2177           4.0/5

  3. onderch01                                   2072           3.0/4

  4. KAPANN                                   1439            3.0/4

  5. GLORIARODRIGUEZ_UNE   1500            2.0/5

  6. sey1t                                           1402            1.0/4

  7. sametneni                                   1013            1.0/3

  8. root129                                       1279            1.0/2

  9. zfruzn                                         1638             0.0/2

 10. kayrasemerci                             1329             0.0/3

 11.Dolar3lira                                   1410             0.0/1

 12. UzunMehmetErdem                 1918             0.0/1


Friday, March 10, 2023

Gambits: Theory and Evidence

 



Abstract of the article "Gambits: Theory and Evidence" by Shiva Maharaj, Nick Polson, Christian Turk, published in Applied Stochastic Models in Business and Industry,Volume 38, Issue 4, July 2022 

Gambits are central to human decision making. Our goal is to provide a theory of Gambits. A Gambit is a combination of psychological and technical factors designed to disrupt predictable play. Chess provides an environment to study Gambits and behavioral economics. Our theory is based on the Bellman optimality path for sequential decision making. This allows us to calculate the Q values of a Gambit where material (usually a pawn) is sacrificed for dynamic play. On the empirical side, we study the effectiveness of a number of popular chess Gambits. This is a natural setting as chess Gambits require a sequential assessment of a set of moves (a.k.a. policy) after the Gambit has been accepted. Our analysis uses Stockfish 14 to calculate the optimal Bellman Q values. To test whether Bellman's equation holds in play, we estimate the transition probabilities to the next board state via a database of expert human play. This then allows us to test whether the Gambiteer is following the optimal path in his decision making. Our methodology is applied to the popular Stafford, Reverse Stafford (a.k.a. Boden-Kieretsky-Morphy), Smith-Morra, Goring, Danish, and Halloween Gambits. We conclude with directions for future 

From the Discussion

 On the one hand, a Gambit policy is not rational; the Gambit leaves open one state of the world where the opponent can win with certainty. On the other hand, the Gambit leads the Gambiteer to advantage with any sub-optimal play from the opponent. 

Thursday, March 9, 2023

Jerome Gambit: Several Stages



The following Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) game is interesting and instructive. It passes through several stages:

a) White attacks

b) Black finds an effective defense

c) Various tactics 

d) A slip by Black

e) White brings home the full point


NN - NN

blitz, lichess.org, 2023

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 

4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Kf8 

This move appears in Alonzo Wheeler Jerome's early analysis of his gambit, specifically in the July 1874 issue of the Dubuque Chess Journal, "Jerome's Double Opening, Third Variation".

7.Qxe5 d6 8.Qc3 Qf6 


Black has a plan - exchanging Queens will blunt White's attacking notions.

According to The Database, this position occurs in 105 of its games, with White scoring 40%.

Is that good? 

Well, if we research The Database for the position arising from the start of the Jerome Gambit - 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+  - we find 25,975 games, with White scoring 51%.

Moving along the regular lines, after 4...Kxf7 5.Nxe5+ we find 16,798 games, with White improving to scoring 57%.

Likewise, after 5...Nxe5 6.Qh5+ in 12,606 games White continues to score  57%.

But all of this changes when we look at the defense 6...Kf8, which appears in 2,017 games, and White's score drops to 48%.

And, like it was pointed out above, after 8...Qf6 White scores only 40%.

9.Qxf6+ 

White is not bothered by exchanging Queens.

Looking at his further play, he might have chosen 9.O-O here, as  9...Qxc3 10.Nxc3 Nf6 would have saved him a tempo.

9...Nxf6 10.O-O Nxe4 11.d3 

11...Nxf2 

This exchange of two pieces for a Rook and a pawn slightly favors White. On the other hand, the retreat 11...Nf6 was probably not appealing. 

12.Rxf2+ 

Stockfish 15 actually prefers 12.c3 Ke8 13.d4 Nd3 14.dxc5 Nxc5 with advantage still to Black. 

12...Bxf2+ 13.Kxf2 Kf7 14.Bd2 Rf8 15.Nc3 Kg8+ 16.Kg1 Be6 


Black is up the exchange, but he still has to decide what to do with hi advantage.

17.b3 d5 18.Re1 Rfe8 19.Nb5 


The threatened Knight fork at c7 can be dealt with.

19...Re7

But not this way. Instead, 19...Bd7 20.Nxc7 Rxe1+ 21.Bxe1 Rc8 22.Bg3 d4 was the way to tie up White's pieces.

20.Bg5 

This is a smh moment for me, as the computer now recommends 20...Ree8, again allowing the Knight fork at c7.

Instead, Black loses the thread of the game. 

20...Kf7 21.Bxe7 Kxe7 22.Nxc7 Rc8 23.Nxe6 Kd6 


White is better. Perhaps his greater enemy at this point is the clock. Simplification helps him.

24.Nd4 Kc5 25.Ne6+ Kd6 26.c4 dxc4 27.dxc4 Re8 28.Kf2 Rxe6 29.Rxe6+ Kxe6 


The first player has a winning advantage. His moves come quickly now.

30.Ke3 Ke5 31.Kd3 a5 32.Kc3 Kd6 33.b4 b6 34.a3 Kc6 35.Kd4 Kd6 36.c5+ bxc5+ 37.bxc5+ Kc6 38.Kc4 

38...g6 39.a4 h6 40.g3 g5 41.h4 gxh4 42.gxh4 h5 43.Kd4 Kc7 44.Kd5 Kd7 45.c6+ Kc7 46.Kc5 Kc8 47.Kb6 Kb8 48.Kxa5 Kc7 49.Kb5 

White won on time