Why do the engines pick this losing move?

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reflectionofpower
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Why do the engines pick this losing move?

Post by reflectionofpower »

I was reading this article https://en.chessbase.com/post/why-chess-players-blunder and curiously I set up the position they were talking about - Carlsen-Aronian, 6th Norway Blitz, 2018 (8)

[d]8/6p1/8/7p/3kP1p1/5P1P/2K2P2/8 w - - 0 1 and all the engines I have pick 52.hxg4?? which is the move Carlsen used and it's completely losing as you can't stop the passer. WHY are the chess engines doing this?
"Without change, something sleeps inside us, and seldom awakens. The sleeper must awaken." (Dune - 1984)

Lonnie
Chessqueen
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Re: Why do the engines pick this losing move?

Post by Chessqueen »

reflectionofpower wrote: Tue Apr 16, 2024 3:31 pm I was reading this article https://en.chessbase.com/post/why-chess-players-blunder and curiously I set up the position they were talking about - Carlsen-Aronian, 6th Norway Blitz, 2018 (8)

[d]8/6p1/8/7p/3kP1p1/5P1P/2K2P2/8 w - - 0 1 and all the engines I have pick 52.hxg4?? which is the move Carlsen used and it's completely losing as you can't stop the passer. WHY are the chess engines doing this?
If you take an engine rated close to Carlsen and Aronian it will NOT pick the Wrong move. Here is Dumb 2.1 rated around 2850 like Carlsen.
NOTE: In my Opinion this Dumb engine can easy beat Carlsen :roll:

[pgn][Event "Computer chess game"]
[Date "2024.04.16"]
[Round "?"]
[White "Dumb-2.1"]
[Black "Dumb-2.1"]
[Result "1/2-1/2"]
[BlackElo "2850"]
[Time "08:36:28"]
[WhiteElo "2850"]
[TimeControl "60+1"]
[SetUp "1"]
[FEN "8/6p1/8/7p/3kP1p1/5P1P/2K2P2/8 w - - 0 1"]
[Termination "unterminated"]
[PlyCount "4"]
[WhiteType "program"]
[BlackType "program"]

1. fxg4 {(f3xg4 h5xg4 h3xg4 Kd4xe4 g4-g5 Ke4-f5 Kc2-d3 Kf5xg5 Kd3-e4 Kg5-g4
f2-f3+ Kg4-g3 Ke4-f5 Kg3xf3 Kf5-g6 Kf3-g2 Kg6xg7) 0.00/34 12} hxg4 {(h5xg4
h3xg4 Kd4xe4 g4-g5 Ke4-f5 Kc2-d3 Kf5xg5 Kd3-e4 Kg5-g4 f2-f3+ Kg4-g3 f3-f4
g7-g6 f4-f5 g6xf5+ Ke4xf5) 0.00/36 12} 2. hxg4 {(h3xg4 Kd4xe4 g4-g5 Ke4-f5
Kc2-d3 Kf5xg5 Kd3-e4 Kg5-g4 f2-f3+ Kg4-g3 Ke4-f5 Kg3xf3 Kf5-g6 Kf3-g2
Kg6xg7) 0.00/35 15} Kxe4 {(Kd4xe4 g4-g5 Ke4-f5 Kc2-d3 Kf5xg5 Kd3-e4 Kg5-g4
f2-f3+ Kg4-h4 Ke4-f5 Kh4-g3 Kf5-g6 Kg3xf3 Kg6xg7) 0.00/40 2} 3. g5 {(g4-g5
Ke4-f5 Kc2-d3 Kf5xg5 Kd3-e4 Kg5-g4 f2-f3+ Kg4-g3 Ke4-f5 Kg3xf3 Kf5-g6
Kf3-g2 Kg6xg7) 0.00/47 1} Kf5 {(Ke4-f5 Kc2-d3 Kf5xg5 Kd3-e4 Kg5-g4 f2-f3+
Kg4-g3 Ke4-f5 Kg3xf3 Kf5-g6 Kf3-g2 Kg6xg7) 0.00/48 2} 4. Kd3 {(Kc2-d3
Kf5xg5 Kd3-e4 Kg5-g4 f2-f3+ Kg4-g3 Ke4-f5 Kg3xf3 Kf5-g6 Kf3-g2 Kg6xg7)
0.00/52 1} Kxg5 {(Kf5xg5 Kd3-e4 Kg5-g4 f2-f3+ Kg4-g3 Ke4-f5 Kg3xf3 Kf5-g6
Kf3-g2 Kg6xg7) 0.00/51 2} 5. Ke4 {(Kd3-e4 Kg5-g4 f2-f3+ Kg4-g3 Ke4-f5
Kg3xf3 Kf5-g6 Kf3-g2 Kg6xg7) 0.00/52 1} Kg4 {(Kg5-g4) -0.05/54 2} 6. f3+
{(f2-f3+) -0.05/56 2} Kg3 {(Kg4-g3 Ke4-f5 Kg3xf3 Kf5-g6 Kf3-g2 Kg6xg7)
0.00/58 2} 7. Kf5 {(Ke4-f5 Kg3xf3 Kf5-g6 Kf3-g2 Kg6xg7) 0.00/75 2} Kxf3
{(Kg3xf3 Kf5-g6 Kf3-g2 Kg6xg7) 0.00/100 0} 8. Kg6 {(Kf5-g6 Kf3-g2 Kg6xg7)
0.00/100 0} Kg2 {(Kf3-g2 Kg6xg7) 0.00/100 0} 9. Kxg7 {(Kg6xg7) 0.00/100 0
Insufficient material} 1/2-1/2[/pgn]
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reflectionofpower
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Re: Why do the engines pick this losing move?

Post by reflectionofpower »

Dumb 2.1 is still Dumb and so are the Smart engines. 52...hg4?? is losing instantly as it allows the passer as it allows the winning move h4. All my engines pick h4 after the howler 52...hg4??
"Without change, something sleeps inside us, and seldom awakens. The sleeper must awaken." (Dune - 1984)

Lonnie
Jouni
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Re: Why do the engines pick this losing move?

Post by Jouni »

No they pick drawing fxg4!
Jouni
Uri Blass
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Re: Why do the engines pick this losing move?

Post by Uri Blass »

reflectionofpower wrote: Tue Apr 16, 2024 3:51 pm Dumb 2.1 is still Dumb and so are the Smart engines. 52...hg4?? is losing instantly as it allows the passer as it allows the winning move h4. All my engines pick h4 after the howler 52...hg4??
... means black move and after the correct 52.fxg4 that engines suggest the move 52...hxg4 that is not losing.

Engines do not play the losing move 52.hxg4 that allow for black 52...h4
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reflectionofpower
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Re: Why do the engines pick this losing move?

Post by reflectionofpower »

I think it's the Lonnie Brain engine v.1.0 because I just woke up and thought I found a sleeper. My mistake and apologies.
"Without change, something sleeps inside us, and seldom awakens. The sleeper must awaken." (Dune - 1984)

Lonnie
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Ajedrecista
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Re: Why do the engines pick this losing move?

Post by Ajedrecista »

Hello:

52.- hxg4?? is a disgrace, being gentle. Huntsman sees a checkmate in 15 moves after 52.- hxg4??, h4:

Code: Select all

FEN: 8/6p1/8/8/3kP1Pp/5P2/2K2P2/8 w - - 0 2

Huntsman:
Found 145 tablebases
classical evaluation enabled
[...]
 57/31	03:42	 835.204.012	3.750.287	-M15	e4e5 Kd4xe5 Kc2d3 h4h3 Kd3c4 h3h2 f3f4+ Ke5d6 Kc4d4 h2h1Q f4f5 Qh1f3 g4g5 Qf3f4+ Kd4d3 Kd6d5 Kd3e2 Qf4xf5 g5g6 Qf5e4+ Ke2f1 Kd5e5 f2f3 Qe4c2 Kf1g1 Ke5f4 Kg1f1 Kf4xf3 Kf1e1 Qc2c1+
There were 34,369,634 TB hits to the full set of 3, 4 and 5-man Syzygy EGTB.

Regards from Spain.

Ajedrecista.