Questions tagged [evaluation]
The evaluation of a given position
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Is there any positional assessment that includes a factor for how difficult it is to play the correct moves?
As I understand it, current positional assessments by computers evaluate a position based on optimal play by both players from this point.
i.e. a trap moves that bait an opponent into making a mistake ...
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Extract evaluation data from Stockfish in Cpp
I am working on a chess player-rating system based on engine evaluations. As part of this I would like to extract evaluation data from Stockfish for the top 10 moves in a given set of positions.
...
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Why taking the knight on d5 in Alapin Sicilian is not so good for white
I'm going through some preparation of the Alapin Sicilian.
Studying the opening I reached this position:
rnbqk2r/pp2bppp/3pp3/3nP3/2BP4/5N2/PP3PPP/RNBQK2R w KQkq - 2 8
In which I wonder why it isn't ...
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Winning position after move one?
Question: There are 400 possible two-ply openings; that is, positions that can arise after each player has made one move. Which of these positions, if any, are winning (either for white or for black)...
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Why doesn't Stockfish announce when it solved a position as a book draw similar to how it announces a forced mate?
I notice that when Stockfish has solved a position to mate it announces that checkmate is unavoidable in some number of moves so it's impossible to mistaken a position Stockfish has solved as a win ...
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A complex eight pieces opposite color Bishop endgame
The position, derivated by a variation of the Alechkine Defense, Four Pawns Attack, is the following:
[FEN "3b4/8/1k2B3/6pK/P7/8/6PP/8 b - - 0 1"]
Black to move. Stockfish 14.1 NNUE gives ...
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Why don't chess engines take into account the time left by each player?
Firstly, I am not suggesting that there is anything wrong the way engines are implemented at the moment, by analyzing only the current position regardless of time left by the players. This is great ...
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Why does Stockfish evaluate this position as completely lost?
After thinking for a minute my copy of Stockfish evaluates the position below as +4.7 for white. Why does the computer hate black's position so much?
I know that all things being equal, black should ...
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Why does stockfish make these strange recommendations?
The FEN is:
r2qk1r1/ppp2p1p/2n1bn1Q/4p1B1/8/2P4P/PP1NpKP1/R5NR b kq - 0 1
Clearly black is winning because the white bishop can be captured (with a discovery available if white recaptures). However, ...
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How to analyse positions more accurately as a total beginner?
In this position I thought I was winning with white, like +2 or +2.5. But Lichess Analysis shows evaluation as -1.4.
[Title "Black to move after Ne5"]
[fen "rn3rk1/1p1b3p/p2n1qp1/3PNp2/...
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How many centipawns guarantee winning?
Since the question in this form is somewhat ill-defined,
I elaborate on it so it can be solved by experiment:
What is the maximum centipawn value you can come up with so that the weaker side holds a ...
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Can chess engines recognize equivalence between two positions?
The positions
[FEN "8/4kn2/4br2/8/8/3Q4/4K3/8 w - - 0 1"]
with white to move
[FEN "8/8/8/2Q5/1K3bk1/5rn1/8/8 w - - 0 1"]
with white to move
[FEN "8/2nk4/2rb4/8/8/4Q3/3K4/8 w ...
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Are knights more powerful in Duck Chess?
In the chess variant Duck Chess (full rules), each player moves the shared blocking "duck" piece to any free square on their turn, taking away one or more moves for the opponent.
One ...
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What's the theoretical worst average centipawn loss on LiChess?
Since mate is evaluated as a finite centipawn loss, all games have a finite average centipawn loss. I stumbled upon this Reddit r/chess thread where this game has an average centipawn loss of 1971 vs....
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Will writing a chess engine help my chess?
At first the premise seems absurd - the computer engine relies much more on brute-force search (Shannon's Type A Strategy) over selecting a few strong lines with heuristics (Type B Strategy). But can ...
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Alpha-beta pruning with a silly move
After learning about alpha-beta pruning algorithm for a while, I decided to write a simple chess program. However, when running the program, the computer decides to make a silly move. I don't know ...
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How do you hide evaluation scores in the arena chess GUI?
Is there a way to hide the evaluation scores while playing a game using the arena GUI?
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Why do Engines show a fraction for the "Depth" and "Current Node" values?
Forgive me if this has been asked elsewhere, but I've both Googled and searched here at CSE and cannot find an answer.
When I'm using an Engine for analysis (in this case, Stockfish 15), I've noticed ...
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How would the min max algorithm of a chess engine work in the case of 3 player chess?
I understand that for 2 player chess if an engine is playing white, then the engine uses a min max algorithm, which assumes that black will always make the move that is best for black, or worst for ...
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Imagine your (stronger) opponent plays this Botez Gambit. How to strategise?
My experiment is inspired by Hikaru Nakamura's "Botez Gambit Speedrun". The term "Botez Gambit" refers jocularly to the act of blundering your queen.
Let's say you had the black ...
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Are engines impaired by the 50-move rule?
Are we missing too much from the 50-move rule implementation to engines, whether HCE (Hand-crafted evaluation) or/and NN (Neural Network)?
We know that certain endgames are a win without the rule.
...
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How do I evaluate the value of every piece in Mathematical Chess?
This is Vietnamese Mathematical Chess—
http://cotoan.vnvista.com/rules-en.html
The board contains 11 ranks and 9 files. Each side has ten pieces, numbered from 0 to 9. The board initial layout is as ...
user32381
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Help with evaluating this position
rn2k2r/ppp2p2/4bn1p/2bp4/8/1B3N1P/PPP2PP1/RNB1R1K1 w Qkq - 0 1
I am having trouble evaluating this position, I believe the activity of the pieces is equal, besides the week h6 pawn I cannot see why ...
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Stockfish NNUE vs handcrafted Evaluation
I read up on Stockfish NNUE and as far as I understand it, Stockfish NNUE was (at least in early stages) trained by positions which were evaluated by the hand-crafted eval. function by stockfish.
The ...
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Why do these convergent lines evaluate differently?
I recently analyzed alternative lines for this puzzle on chess.com.
[Event "French Championship"]
[Site "Val d'Isere FRA"]
[Date "2002.08.23"]
[Round "5"]
[...
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Lichess Cloud Evaluation Flaw?
In the following position that's in the Traxler Counterattack: https://lichess.org/analysis/r1b1k2N/ppp1q1pp/5n2/3Pp3/2Bn4/8/PPPP1bPP/RNBQ1K1R_w_q_-_1_9
[fen "r1b1k2N/ppp1q1pp/5n2/3Pp3/2Bn4/8/...
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How does one determine if a book move is objectively better than another?
For example, I have heard the following statements:
After 1. e4 e5 2. Nf3 Nc6, the move 3. Bb5 is marginally better than the move 3. Bc4.
Openings moves such as 1. e4, 1. d4, 1. Nf3, and 1. c4 are ...
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Why does stockfish move quality increase non-monotonically with increasing depth? -- selected moves at depth 3 are worse than depth 1
I have been working on a project looking at how stockfish moves change with increasing computation time (here search depth), and have found something peculiar - namely that the quality of moves that ...
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How to filter out games with evaluation from large PGN file?
I have a huge 100M games in one PGN file - some % of it is stockfish evaluated, I want to use pgn-extract to extract those evaluated only, Is there a way of doing so?
examples of games with and ...
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Python Efficient Board Scoring Function To Use As Placeholder
I'm building a chess engine in Python. I'd like to find a board evaluation function that would be easy to put into my engine as a placeholder while I work on other aspects of the engine first.
I would ...
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Analyse a blunder
Black (me) to move.
I took the knight at f3 with my knight at e1. However, Lichess analysis shows that this move is a blunder, and suggests to take the bishop at g2 instead.
IMO, I am winning no ...
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Using pgn-extract to output FEN + evaluation
I'm using pgn-extract to convert a PGN database into FEN + evaluations. My goal is something like this:
1. e4 e6 2. d4 b6 3. a3 Bb7
Into this:
rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 ...
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Why wasn't Ne5 a mistake when I could just win the exchange in one move?
I had this position arise in a game:
[FEN "4qrk1/3rppbp/1p4p1/p2P4/1pBP1B2/1P2PN2/5PPP/R2Q1RK1 w - - 2 21"]
[White "Kevin"]
[Black "lichess AI level 3"]
1. Ne5 {I ...
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Why is this position in the 3.d4 d5 Petroff equal?
I'm trying to learn some theory about the Petroff and was reading about the 3.d4 d5 sideline. Eventually, the position below is reached.
[FEN ""]
1.e4 e5 2.Nf3 Nf6 3.d4 d5 4.exd5 exd4 5.Qxd4 ...
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How to evaluate whether a position will result in a draw vs a decisive outcome?
Suppose 2 positions both have 'equal' evaluations according to the engine, but the first position has strong, easy-to-spot moves which lead to a drawn endgame, whereas the second game is extremely ...
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What do chess engine evaluation scores (+1.3, -3.2) really mean?
I know that chess engine evaluations like +1.3 intuitively mean that White is evaluated to have an advantage equivalent to 1.3 pawns of material, or that -3.2 means that Black is evaluated to have an ...
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Does blitz change the relative value of position vs material?
The way I see it, true gambits trade material for position, which in turn could give you opportunities to regain more material. However, in blitz play, you are less likely to notice those ...
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Techniques used for Stockfish engine selectivity
Example puzzle (I'm sure there are numerous that fit this bill):
[FEN "rnbq3r/pppp4/3b1pkp/5p2/2BP4/4P3/PPP2PPP/RN1QK2R w KQ - 0 1"]
[Site "Earth"]
[White ""]
1. Qh5+ ...
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Why is this seemingly quiet and normal position actually -3?
rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq - 0 1
[Event "Casual Blitz game"]
[Site "https://lichess.org/GETmjlLj"]
[Date "2021.08.15"]
[White "WMArsyHuda&...
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How do you evaluate this position?
rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq - 0 1
[Date "2021.08.14"]
[Result "0-1"]
[UTCDate "2021.08.14"]
[UTCTime "22:01:55"]
[...
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Detailed Stockfish Evaluation Function
Stockfish contains the nice 'eval' command that prints out the detailed score of its static evaluation function. It regards Mobility, Material, Bishop, Rooks, etc. However, I was wondering if there ...
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Why is h4 much better than h3?
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
[Event "Rated Rapid game"]
[Date "2021.08.09"]
[Result "0-1"]
[Variant "Standard"]
[TimeControl &...
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Examples where top engines in a tournament match don't agree in evaluation
I'd like to know about computer games of some recent tournaments where two top engines diverge in evaluation of a position, in the sense that both think are winning the game (or both losing). I saw ...
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Why is 11. .. h6 such a bad move?
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "?"]
[Black "?"]
[...
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Can this '+3.9' advantage be converted to a win?
I reached this endgame, which Stockfish 10+ evaluates as +3.9, but failed to convert it to a win. I feel that it may be a draw after all. Is that the case?
[Title "White to move"]
[FEN "...
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How to score a certain move in a PGN, for how well opening theory is followed
I am making a bot that plays opening moves from a PGN. When the player reaches a position out of PGN, I want to give a score to the player how well he followed the PGN. What kind of statistics can I ...
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Is there an engine evaluation technique that factors in 'time'?
An interesting game played out between Wesley So and Levon Aronion1:
[title "Wesley So vs Levon Aronian"]
[fen "rn4k1/p2bP1b1/2q5/1pp2p1Q/2p5/8/PP3PPP/3R1RK1 w - - 0 1"]
So was in ...
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Is this a draw despite the Stockfish evaluation of −5?
I reached this position as Black:
[Title "Black to move"]
[FEN "8/8/8/3q4/6kp/7R/6P1/6K1 b - - 3 46"]
And I felt that I cannot make any progress and so it feels like a draw. ...
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Why are lots of different moves usually considered equivalent in the opening, but not in the middlegame?
When you go to websites like chess.com and analyze your games, you'll notice that most of the first moves are marked as being "book moves"—which I assume are considered equivalent to each ...
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Why is this position considered to give white a significant advantage?
In this position, black's king is safe, has a secure queenside pawn structure, and has taken out white's left pawns and is up 2 points of material. Despite this, lichess evaluates this position at +3....
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