6 votes
Accepted

Why is this knight outpost from a Semi-Slav an inaccuracy?

1.Ne5 here is misguided because it leads to the exchange of minor pieces, relieving Black of their relative lack of space and helping them to engineer the freeing ...c6-c5. After 1...Nfd7! Black bumps ...
Evargalo's user avatar
  • 16k
4 votes
Accepted

Why is Nf6 a blunder here?

Because after Bxf6 gxf6 there is Qxf6, which wins a pawn, threatens the rook and threatens mate on f7. You can castle, but then the king is exposed by the missing g pawn. Your only other option is Rf8....
Especially Lime's user avatar
4 votes
Accepted

Why does Stockfish only gives -28 to a game with only a W pawn and a B rook remaining, while it should be resolved in perfect play?

You probably are running it at a shallow depth. My old version of Stockfish recognizes that there is a mate when it gets to depth 32. There are tablebases available, which engines like Stockfish can ...
D M's user avatar
  • 19.3k
3 votes

Is there an online chess evaluation engine with a REST API?

I'm a bit late, but https://stockfish.online is a REST GET API for Stockfish. Make requests with a FEN string, depth, and mode. For example, making a GET request to https://stockfish.online/api/...
cobbsaladluv's user avatar
3 votes

Statistical distribution of centipawn losses

This is an interesting question. We can plot the distribution using data from the Lichess database of games that have evaluations. I have held constant: Player rating Time-Control (here I used Blitz ...
Simon M's user avatar
  • 495
2 votes

Why 6.Qf3 is bad in this game/position?

As has been pointed out elsewhere in this thread, the correct move is 6.a4. This move is awkward for black to face. White is threatening to just take the pawn on b5, and the only good way for black to ...
Scounged's user avatar
  • 7,998
2 votes

Why 6.Qf3 is bad in this game/position?

The drastic change in evaluation isn't that much about the queen misplaced on f3 but rather about the necessity to play a4 as soon as possible. If you go 6.a4 right now, Black can't reply with ...c6 ...
David's user avatar
  • 16.3k
2 votes

Trying to understand evaluation

From a human perspective, this is what I see ... Black's king is very unsafe. White's is completely safe. The light squared weaknesses around black's king are devastating. White has the bishop pair ...
JP Alioto's user avatar
  • 429
2 votes

Trying to understand evaluation

The clear advantage for white is development! Because of black not having a LSB and the placement of whites pieces, black cant trade off the E6 bishop after Qb3 protects the bishop.That bishop hems in ...
anti - Marshall's user avatar
2 votes

How do we exactly establish if a position/center is "open" or "closed"?

I think you are looking at this a bit backwards. You're asking whether or not the position is likely to remain open or closed and want to use that to direct your plans. The game is yours to make. You ...
Nelson O's user avatar
  • 715
1 vote

Is there any engine that is capable of evaluating the worth of a single piece in a given position?

Engines can evaluate the position as a whole with great precision. This is not the case; the only thing an engine evaluates is that engine's evaluation function. Imagine a chess engine FishStock, ...
Kostya_I's user avatar
  • 1,902
1 vote
Accepted

How are piece phase values for tapered evaluation/phase calculation calculated?

Keep in mind that the phase is supposed to distinguish between middlegame and endgame evals. The larger the value of phase, the more impact it has on determining whether we're at an endgame. Human ...
Allure's user avatar
  • 27.2k
1 vote
Accepted

How to implement Zobrist tables?

I will try to answer some of the questions. Is the question how large your hash table should be? I think the simple answer is, make it as big as you can on your system. If you have 16 GB of RAM you ...
koedem's user avatar
  • 3,441
1 vote

Stockfish evaluation bar like chess.com

The evaluation on chess.com is simply a graphical display of the result of the eval command of the UCI interface for Stockfish. Likely they are using a WebAssembly version of the engine. How you ...
JP Alioto's user avatar
  • 429
1 vote

Why 6.Qf3 is bad in this game/position?

The reason is simple (credits to FM Dr. Hauke Reddmann pointing it out in a comment): You are down a pawn without compensation! Black took a pawn that you won't get back after 6.Qf3 and you don't even ...
Hauptideal's user avatar
  • 6,172
1 vote

How do we exactly establish if a position/center is "open" or "closed"?

Well, we really don't. We can use some heuristics like: The number of pawns currently in the center. Whether those pawns are attacking or blocking each other. How easy/convenient it would be for ...
David's user avatar
  • 16.3k
1 vote

How do we exactly establish if a position/center is "open" or "closed"?

In the old days, I remember reading that open games were those that started 1. e4 e5 (actually, P-K4, P-K5, this was a while ago!) Semiopen were 1. e4 anything else and closed were ones that started ...
Peter Flom's user avatar

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