Why am I losing so much more often with black (newer player)? I have played about 125 games so far online and am rated 834 in rapid (I did play a lot as a child but not in many years) and I have double the win percentage with white pieces that I do playing as black. Is there any logical reason to this other than some confounding factor I'm not thinking of? I know that white does win slightly more often than black at higher levels and the engine favors white from the outset. However, I think 72% win rate with white and 37% win rate with black is quite drastic. Maybe 125 is too small a sample size and my stats will regress to the mean as I play more, but I actually feel like I'm doing something wrong with black. Almost a feeling of discomfort and constantly responding rather than making plans. Can someone give me some advice on a different way to look at playing with black?
My only theory is that while I don't play with any specifically named openings with either side, I do begin every game along the same lines with white, so maybe I am playing a commonly used opening with white and my opening with black is just not optimal.

It's hard to say without analyzing your games but I imagine there are two parts of your problem.

General lack of opening principals

Investing time in learning concepts like "what is the goal of the opening" can be just as valuable as practicing tactical puzzles. Openings aren't just about memorizing move sequences but there are plenty of general concepts that can improve your game.

Lack of confidence specifically with black

You might subconsciously discount black's ability to play great games. You could look up some grandmasters game analysis videos where black wins for some inspiration. You can find some incredible presenters online.
You also might want to consider changing up the opening systems you play. I imagine you mostly play a lot of e4 e5 games. Consider learning a little bit about openings like the caro-khan or the French. With a little preparation you'll catch a lot of new players by surprise. Even without prep chances are you'll be taking your opponents out of their comfort zone too, hopefully that can even the playing field.


How should one play as Black vs. the Ruy Lopez Exchange Variation? As the title above states, how should one play as Black vs. the Ruy Lopez Exchange Variation? In other words, after `
 [FEN ""]
1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Bxc6 dxc6

(The Exchange Variation), White's Pawn structure is superior, and an endgame would eventually favour him, for the potential Passed Pawn. But Black's compansation, it is said in the books, is in the Bishop Pair. But in practice, what strategy (or strategies) should Black adopt, to make this a real thing and not just an abstract advantage?
`

Do not exchange pieces, since this will bring White close to a winning endgame.

Use your two bishops and open up the board, so that you get a better middlegame.

Put your doubled pawns into action.


What should be the value change if pawns are doubled? I am creating a chess engine and I am creating a heuristic to change the board evaluation if there are doubled pawns. Now, I have no experience in creating engines, so I figured I would ask this site on how much to change it. The values of my pieces are as such:
King - 10,000
Queen - 100
Rook - 50
Bishop - 30
Knight - 30
Pawn - 10
I am thinking that doubled pawns should be -5 points, tripled -10 points, quadrupled -20 points and so on.

Start with whatever and tune it.
That's how chess engine programming works - you start with some number, and then tune it. For example you start with -5, then create another version with -10. You get the two engines to play against each other, and the one that wins more often is the "correct" version that you keep.
Of course as pointed out by other answers, doubled pawns aren't necessarily bad, so the next step is to start incorporating more features that can mitigate the doubled pawn penalty. For example you could say that if you have a pawn on an adjacent file that is defending the more advanced doubled pawn (e.g., a pawn on f3 given doubled pawns on e4 and e3), then remove the doubled pawn penalty. And then the testing process would start again, you take this patch and create a new fork, then get the two versions to play each other and retain the stronger version. And then you could tune, e.g. maybe "remove the doubled pawn penalty" is too strong, perhaps it should be "take only half the doubled pawn penalty", etc.
On another note, there is no "standard answer" to how large the doubled pawn penalty should be. Different engines will prefer different values - it depends on the rest of your evaluation function & search function. See this article which contains a paragraph about adding tripled pawn penalties to Ethereal:

You might ask- why can't someone just write a better evaluation function? The answer is that people are trying, but it's difficult. Andrew Grant told me that he tried to add a penalty for tripled pawns (because they're obviously terrible!), but for whatever reason the engine became weaker with that penalty. Code for positional subtleties is extremely unlikely to add strength.


Playing against the 2...c5 systems in the Kings Indian Attack against the French [FEN ""]

1. e4 { Shockingly, I did not play 1.a3} 1... e6 2. d3 c5

This can still transpose into the main line with 3...d5. But I played a game with this yesterday, and my opponent played Nc6, d6, g6, Bg7, Nge7, e5, h6, O-O and eventually built up towards playing f5 (not in that order though). I'm assuming that that was theory, since he blitzed it out pretty quickly and got a slight advantage. I’m wondering if anyone knows how to play against it. Does anyone know how play against it?

I will try to give a few ideas based on the limited information, and trying to follow some common sense regarding development and the moves your opponent played.

    [FEN ""]
 1. e4 e6 2. d3 c5 3. Nf3 Nc6 4. g3 (4. Be2 g6 {4...d5!} 5. O-O Bg7 6. c3 Nge7 7. Be3 d6 8. d4) 4... g6 5. Bg2 Bg7 6. O-O Nge7 7. c3 d6 8. Re1 e5 9. a3 O-O 10. b4 a6 11. Be3 b6 12. Nbd2 h6 13. Rb1 Be6 14. Qc2 *

I am not a big fan of the King's Indian Attack. Frankly, your opponent's response, which I like a lot, with an early g6 tends to really blunt the main k-side attacking premise that makes this opening fun for white sometimes, and thus, the main reason to play it. The other thing is that in this c5 variation, black always can go for the normal Sicilian "equalizing" move, d5 with little trouble.

The fact is that your second move cedes space to black from a very early stage, so it is hard to believe that you will be able to gain an advantage out of the opening. You might want to hide your intentions a little more too with 2.Nf3, 3.g3, and only then, play d3 before showing your hand. He might not play a line with g6.

As to what to do, because g6 really makes it hard to attack his king as in the main lines, the line I gave sets you up to play the re1 to d1 and the ra1 to b1 and eventually to play bc. If he opens the b-file, you will try to play on it, and you are probably better placed to use it, or if he opens the d-file, you can play for d4. If you really do not have play on the k-side, you have to look at the center and q-side.


In the Delayed Open Catalan, what is the best move after 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8? I'm building my White repertoire.

After 1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8 we reach the following position:

[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8

My question is: which move should I choose?

Qc2

Qb3

Qa4

What are the advantages and disadvantages of each one of them?

I would like to choose the move which (on average) leads to the most positional, solid, quiet and strategic positions (not sharp and tactical positions).

There are only 6 games which reached this position in my opening database: White played 10. Qc2 in 3 of them, and White played 10. Qb3 in the other 3 of them.

Komodo 8 says after a depth of 26 plies (2 hours):

Qc2 : +0.22

Qb3 : +0.36

Qa4 : +0.37

Stockfish 5 says after a depth of 31 plies (1 hour):

Qc2 : +0.18

Qb3 : +0.32

Qa4 : +0.32

Gull 3 says after a depth of 25 plies (5 hours):

Qc2 : +0.00

Qb3 : +0.30

Qa4 : +0.22

I play the Catalan in a constant basis, and in this position I would play Qb3 for the following reasons:

10.Qa4 => does not look that great because at any moment black can play Bd7 (gaining a tempo on the queen) and then Bc6, and thus, releasing some of the pressure in the light squares of the queenside.

Line:

[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8 10. Qa4 Bd7 11. Qb4 Bc6

10.Qc2 => leave the queen "tactically vulnerable" and, in some lines, disconnect the queen from the knight in c4 (after Nc3, for instance). Two SAMPLES lines to consider:

Example 01:

[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8 10. Qc2 Bxc5 11. Nc3 Bxf2+ 12. Rxf2 Qxc4

Example 02:

[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8 10. Qc2 Bxc5 11. h3 b5 12. Ncd2 Bxf2+ 13. Rxf2 Qxc2

I'm not saying in any way, shape or form that these lines are good, I'm just trying to point out the tactical themes that could arise from such positions.

10.Qb3 => There is no tempo gaining move on the queen. The knight on c4 would be protected even after the natural move Nc3. And you keep the pressure on b7.

The three moves are good but if you want a quiet, positional game but maintaining long term pressure I would recommend Qb3. The other 2 keep some dynamism in the position and could bring complications in the long run.


A free chess opening database? I'm looking for a chess opening database that is reasonably complete and computer-readable. It should be available either under a liberal free license (like, say, CC-BY, no GPL), or under reasonable commercial license.

Are there any?

No.

The reason for a no, lies in your question. If you want "liberal free license" you are asking for free software and “free software” is a matter of liberty, not price, since you specifically said "(no GPL)" then your request is contradictory.

However, if you do want “free” (as in “free speech,” not as in “free beer”) opening database, there are some options.

You can build small (1 MB), medium (25 MB), or large (58 MB) opening books for Crafty, that will give you enough material for a couple of years, maybe even more.


How to use Arena GUI outputs in a python program I'm currently developing a self-playing chessboard on which I'd like to implement an Artificial Intelligence (AI) (currently it's Stockfish. I would like to know how I could, if I can, export Arena GUI's (other ideas are welcome) to somehow position my stepper motors correctly. Does anyone know of a way?

I'm writing the code in python.

I think using the Arena GUI may be an overly complex way of attempting this.

Instead, go for the Arena engines. Many (all?) implement the UCI protocol, which would allow your application to basically send move information to the engine, and get its responses (under the chosen set of parameters) back.

Some chess engines use other protocols, and not all may be open or freely available.  UCI (see https://www.chessprogramming.org/UCI for more info) is reasonably well known, so you should be able to get answers to any problems you might have.


From Mate-in-3 to Mate-in-1 Here is my new problem in 3 steps - the key designates here the piece that moves first in the solution. An other way to reach a mate in one I hope you'll enjoy...
    [Title "From Mate in 3 to Mate in 1"]
    [FEN "5R2/p2k1p1P/1P1P1PPr/bPpKBN1p/1pR3n1/7B/2P2N1P/1b6 w KQkq - 0 1"]

Here is the starting position. White to move (at each step)
Step 1 : Mate in 3
Step 2 : Remove the key then Mate in 2 (same starting position with one piece less)
Step 3 : Remove the key then Mate in 1 (same starting position with two pieces less)
Edit. For Step 3, say White R8 hasn't capture any piece at last move.

Spotting potential mates isn't too difficult. There are a couple of obvious ones involving the b and h pawns which aren't far off from promoting. An immediate b7 threatens b8=N# for example. It can only be stopped by Bc7 but then after dxc7 black has Nxf6+ and the mate is delayed beyond 3 moves.
Pushing the h pawn is more promising. If it weren't for the black rook on h6 then it would be mate in 2 with Rxf7+ followed by h8=Q#. That can be fixed by starting with Nxh6.
Going back to the initial position it's worth looking at possible black spoiler moves, moves which either deliver check or threaten check which delay the mate. We've already seen that Nxf6+. Also Ne3+ and Ba2 threatening Bxc4+ if black is given the opportunity. If the mate is going to involve the Bishop on h3 delivering the coup de grace then we also have to watch out for Rxg6 followed by Rg4 blocking the check.
That said the key move of Nxh6 solves a lot of these problems. It gets rid of the pesky rook and it pins the pesky knight on g4. Hence I think the first part goes like this:
[Title "First part - mate in 3"]
[fen "5R2/p2k1p1P/1P1P1PPr/bPpKBN1p/1pR3n1/7B/2P2N1P/1b6 w KQkq - 0 1"]

1. Nxh6 Ba2 {threatening to disrupt with Bxc4+} 2. Rxf7+ {thank goodness this comes with tempo and black has no time for the disruptive check} Ke8 3. h8=Q#

So, remove the f5 knight and try and mate in 2. The b7 push is obviously too slow so the obvious line to take is mating with the h3 bishop.
The obvious first try is Nxg4. The problem is that black is not obliged to take with hxg4 allowing Bxg4#. Instead black has the tricky Rxg6 followed by Rg4 to block the mate. Mate in 2 is denied.
So, how to stop this defence? The cunning answer is to take with the rook. Then Rxg6 can be answered by Rxg6# or, to rub it in, Rg5#. What about Ba2+? That was one of black's disruptor moves. Does that stop us? No! We can just move the rook back to c4, blocking the check and delivering a discovered mate.
So:
[Title "Second part - mate in 2"]
[fen "5R2/p2k1p1P/1P1P1PPr/bPpKB2p/1pR3n1/7B/2P2N1P/1b6 w KQkq - 0 1"]

1. Rxg4 (1. Nxg4? Rxg6 2. Ne3+ Rg4) hxg4 2. Bxg4# (1...Rxg6 2. Rxg6#) (1...Ba2+ 2. Rc4#)

That then leaves this as the final problem. As @wimi points out the key here is to spot the possibility that black's last move could have been c7-c5 meaning that bxc6 en passant would be checkmate. Great spot by @wimi.
[title "Third part - mate in 1"]
[fen "5R2/p2k1p1P/1P1P1PPr/bPpKB2p/1p4n1/7B/2P2N1P/1b6 w KQkq - 0 1"]

1. bxc6#


Which are better, Knights or Bishops? I have always thought Bishops were better - I know that a KBB vs. K endgame is easily won, whereas KNB vs. K is difficult, and KNN vs. K is impossible; but then again, some people prefer Knights.  I realize there is a reason for each receiving the same point value (3) - they are so similar in strength, the Bishop on open lines and the Knight in close quarters.

But is there any concrete study on the point, such as someone analyzing thousands of games in which one player began the game with two Bishops and no Knights, and the other had two Knights and no Bishops?

It depends on the board position. Both have equal points. But in a closed position, i.e, when the mobility of our pieces are blocked by the opponents pieces, knights have advantage. On more open board positions, bishops have advantage.


What should a beginner focus on to improve his level? I've learnt chess only about 1 month ago. Of course, my first game was terrible. But with reading some tips I've proceeded a little. Learning basics of few openings (like Spanish, Vienna and Urusov) increased my level and so did learning a bit about tactics (I can do a fork or a pin when possible) but now I don't know what to do?

Should I read books on opening Theory? Or on endgame? I don't know how to make a plan. Sometimes in the mid-game, I don't see a good move. There is no great attack against me and also I did not make an attack but I'm not sure how to launch one so sometimes I tend to do a random move or just proceed to get my peaces more connected and controlling more place but I feel lost. So what would be your advice?

Is it better to focus on tactics and so? (Which resources do you recommend? text? app? etc ) or the ability to make a plan? (resource?)

Thank you in advance

A bit of everything, really.

Observe

Subscribe to a few youtube channels, turn up to tournaments, do something where you can analyse players who are better than you and try to understand their moves. This will give you a general idea of how to play, but won't teach you much compared to just playing.

Openings

Try to learn some basic opening ideas and maybe even a few more lines. Learning specific openings is only useful when you play exactly those openings, so you could either learn every opening in theory, or learn the main ones and a few opening techniques which would work across many openings.

"Opening ideas" Includes things such as piece development and centre control, but also subtle things too:

  Learning the ideas behind openings means, rather than memorizing long theoretical variations it is important to know where to put your pieces and make a pawn formation and build a long term plan accordingly. Every opening is unique and has its own ideas, some openings require fast and aggressive ideas and motifs and some openings it is important to play slow and just maneuver your pieces to a good square.

This post by GM arunabi is a great material that looks into opening ideas.

Middlegame

Try to  brush up on things like positional play and trading. Learn a little about pawn structure and when to castle. You can set up your board to the end of an opening line and play against someone else or a computer to acheive this. Watching GM games on YouTube helped me a lot, since you begin understand how trading works and how the value of pieces can change. @Bad_Bishop wrote an amazing answer to my question about trading minor pieces which you should read.

Endgame

Practise a few endgames and start to calculate best moves in difficult endgames. Playing an endgame as the losing side and trying to draw may even be more beneficial to your learning. You can easily do this by playing against a computer and starting in a losing position. You can take these positions from famous games, your own games, or random games from a chess database where there was a clear winner, and starting ten or so moves from the end.

Review

If you have records of your games, go and find out where your mistakes were. After every new game you play, run back through it and find where the turning points of the game were. Try to pinpoint mvoes which caused the play to shift. Identify the tactics used and go and learn those, so you can spot them next time.

The most important part is to keep playing games and reviewing them to find your own weaknesses. Once you find them, stamp them out and repeat.


Fritz Online will not finish game? Fritz Online will play all the way to the point where there's mate in one move.  In other words, if you are white and Fritz is black it will stop playing (moving) at the point any black move will be followed by mate on the part of while.

This is fine, I can read the Fritz console in the lower right and it will say something like "White mates".

The problem is that I want my kids to play with Fritz Online and this modality is disorienting to them.  They want to see the game play through to the actual end and get the satisfaction of completing the mate.

Is there a setting that will cause Fritz Online to play through to the end just like any regular chess program?

Just tested it and it may have been fixed. It let me complete the mating move.

Just in case, the site is https://fritz.chessbase.com/


How many points is each chess piece worth? I am a beginner at chess; please answer this question for me.

How many points is each chess piece worth?

The answer by MikroDel gives the commonly-used "Reinfeld values" of pawn=1, bishop=knight=3, rook=5, and queen=9 (kings are essentially worth an infinite number of points, because the game ends if it is lost). While this is a good guide, chess is rarely that simple. Many books will give the value of bishops as 3.5 instead of 3, simply because they are often much stronger than knights in endgames and open middle-games.
There are other things to take into account as well. For example, bishops are much stronger if you own both of yours, but you opponent has already lost/traded one or both of theirs. The nature of the position can also affect the worth of individual pieces, as a position that is completely blocked up might leave a bishop with no useful squares to go to while a knight may be able to jump straight over the obstruction.
Another example of how the Reinfeld values can be misleading is that 3 minor pieces (bishops and knights) are often more powerful than a single queen, provided that they are used properly.
For some further reading, you might also want to take a look at http://en.wikipedia.org/wiki/Chess_piece_relative_value which has a much more detailed explanation.


Is AlphaZero deterministic? AlphaZero searches for moves using Monte Carlo Tree Search (MCTS). As I understand MCTS, it takes the root position, goes to a child node, and then plays random moves until one side wins. Since the moves played are random, does that mean AlphaZero is also random?

Related: this question shows that Stockfish and other conventional engines are indeed deterministic if one looks only at the number of nodes evaluated. I don't know however if the same applies to AlphaZero.

No. MCTS is generally not deterministic. However, it's not that bad given how powerful Google's machines were.


Heavy piece endgame with 2 extra pawns-how to convert? 1r6/5pk1/2q1p1pp/3p4/r2P4/2P4P/PPQ2PP1/R3R1K1 w - - 0 1

It's White to move.

White is 2 passed pawns up, but Black is very active. I'm sure objectively White is winning, but how? Black will attack and force me to move my a or b pawn, but the moment I move one pawn, Black will sink a rook next to it (a3 or b3) and paralyze my pieces.

1r6/5pk1/2q1p1pp/3p4/r2P4/2P4P/PPQ2PP1/R3R1K1 w - - 0 1

1. b3 Ra7 2. a4 Rab7 3. Reb1 Rc7 4. b4 Qxc3
5. Qxc3 Rxc3 6. b5 Rcc8 7. b6 Rb7 8. a5 Ra8
9. a6 Rbb8 10. b7 Ra7 11. Rb6 Kf6 12. Rab1 Ke7
13. Rc6 Kd7 14. Rbb6 Rxa6 15. Rxa6 Rxb7 16. Rcb6 Rc7
17. Ra8 Ke7 18. Rab8 Kf6 19. R6b7 Rxb7 20. Rxb7

You should move your pawns forward first since the a-pawn and b-pawn are passed. Do not allow black to blockade them. If pawns get blockaded, switch your attack to the kingside, and try to mate black king. You should move your queenside pawns forward quickly, and support them...if not, you might lose your chance.

Some very unpolished examples.

1r6/5pk1/2q1p1pp/3p4/r2P4/2P4P/PPQ2PP1/R3R1K1 w - - 0 1

1. b3 Ra3 2. c4 Rba8 3. c5 Rb8 4. Rec1 Qb7
5. c6 Qc7 6. Qc5 Ra5 7. Qc3 Ra3 8. Qg3 Qb6
9. Qe5+ Kh7 10. c7 Rc8 11. Rc5 Ra5 12. Rxa5 Qxa5
13. Rc1 Qxa2 14. Qf6 Qxb3 15. Qxf7+ Kh8 16. Qf6+ Kh7
17. Qe7+ Kh8 18. Qd8+ Rxd8 19. cxd8=Q+ Kg7 20. Rc7#

If rooks want to blockade, you may have to sacrifice pawns to promote and queen one pawn.

Do not forget your king safety. This variation is forcing, and promotes the pawns.

If you do not gain space on queenside, black can kill your pawns because of better mobility, so you must keep your edge and not fall from it.


How to combine Basic Strategies to a winning-system Suppose one want to have a strategy so one can win over a "normal/average" chess-player. I was thinking that there was a set of strategies which could be combined so that  one could memorize it? Say the opening and the middle game. Then one could always win over a "non experienced" chess-player.

That's not how chess works.

Chess has too many possibilities for a "one size fits all"-strategy or set of strategies that you could learn by heart.

At the risk of repeating myself: Learning chess is like learning a language. It's kind of hard to learn a set of sentences that allow you to win any debate against an average debater.

Instead, "understanding" is the key. Languages and chess have to be learnt the hard way: Maybe some rote learning can be beneficial, but mostly you'll need lots of practice and exposure to "good chess"/correct language until you have developed an intuition about sentence structures/connotations/positions/tactics etc.


How to checkmate in an altered version of chess If you know the name of the chess variant I'm trying to describe, please leave it in an answer.
My friend and I have conceived an (most likely already thought up, nevertheless very fun) idea of chess where 2 moves take place at a time. The main rule we have that concerns checkmating in this variant is that you can move through check so long as you don't end up in check at the end of the second move. (This also means you  can move another piece before getting your king out of check)
How would one checkmate in this situation? An even situation would be optimal for the response, I know how one could checkmate with an inordinate amount of pieces.

This is basically Marseillais Chess, the main difference between it and your version is that a player can't move into and then out of, check. When a player gives check on the first move, he then loses his second move.
Additionally, the most commonly played version is "balanced", with white only making one move on the first turn, so as to not give White too much of an advantage.
One would checkmate just as in regular chess.


Is there a balanced chess system where players of unknown skill can have an equal chance of winning? Is there a chess system where you can make players of differing skill levels compete against each other with an equal chance to win without using different chess variations?

This system should give good players and bad players a level playing field where both of them can win.

Yes.

The way I've done this in the past is to play a series of games with clocks starting with 10 minutes each on the clocks and then the rule for subsequent games that the winner of the previous game gets one minute less and the loser one minute more. This quickly stabilizes at a level where both players have good chances of winning.


Does the Caro-Kann or the Tartakower System of the Queen's Gambit Declined help with positional skills? In the following Wikipedia biography on Gary Kasparov, I read the following:

  From age 7, Kasparov attended the Young Pioneer Palace in Baku and, at 10 began training at Mikhail Botvinnik's chess school under noted coach Vladimir Makogonov. Makogonov helped develop Kasparov's positional skills and taught him to play the Caro-Kann Defence and the Tartakower System of the Queen's Gambit Declined.

This got me thinking: does the Caro-Kann or the Tartakower System of the Queen's Gambit Declined help with positional skills or was this probably due more to the fact that Makogonov was familiar with it?

Based on the sentence syntax I don't believe that the author is intending to make a connection between the mentioned opening systems and positional skills. Every strong player must have good positional skills and must also be a good tactician. You could not become a world class player without both.

Both of these openings do have strong positional ideas and Makogonov (who would be classed as "positional") played them both. So it is likely that he taught them because he believed that they were instructive and because he was familiar with them.


Custom chess (game) engine Is there a chess engine which you can use regardless of the game's rules? For example, I want to create my own chess version in which queen will also be able to move as knight, or just a 10x10-square version of chess. I am wondering, is there an engine in which I can put "my rules" in, and then not only it will be able to play, but also it will beat any human in that version?

I know that Stockfish is open source, but how easy would it be to edit it according to "your rules?”

If not, when it is expected to happen? I mean during the next 5 years, or after 20 years.

Yes, there is. The FairyMax engine is quite flexible, it changes how it plays chess from a configuration text file. Please take a look at the official version:

http://home.hccnet.nl/h.g.muller/fmax.ini

Do you see Capablanca chess, where the board is bigger? Do you see all those variants?

Some links:

http://www.open-aurec.com/wbforum/viewtopic.php?f=19&t=53353
http://www.open-aurec.com/wbforum/viewtopic.php?f=2&t=53826

You'll need to learn how to use the file. Please ask on the Winboard forum for any further assistance (I don't think there is proper documentation, you just need to ask). Pay close attention to H.G.Muller, he is the man who did all of that.

Stockfish doesn't allow easy transition to a variant. It's still possible but you'll need to battle at the source code level. Not simple. Nothing will change unless you rewrite Stockfish from scratch. Use Winboard/Fairymax, not Stockfish. Winboard/Fairymax is the best variant engine available.


Sicilian defense : what's the best answer to 2.Qh5? I've seen one video on YouTube about the Sicilian defense and wanted to try it on a game. In this game, my opponent played 2. Qh5, trying to capture c5,and if b6 then Qd5 and rook is taken whatever I play.

White had a very powerful and aggressive opening, giving me no rest or tempo to develop my pieces. He however did a blunder on the 12th move and resigned the game after losing his queen.

So, what would you recommend to play after Qh5 ?

[FEN ""]
[Event "Live Chess"]
[Site "Chess.com"]
[Date "2013.03.16"]
[White "CNaveen1403"]
[Black "ychaouche"]
[Result "0-1"]
[WhiteElo "1340"]
[BlackElo "1320"]
[TimeControl "30|0"]
[Termination "ychaouche won by resignation"]

1.e4 c5 2.Qh5 d6 3.Bc4 g6 4.Qf3 Nf6 5.d3 Bg4 6.Qg3 a6 7.Bg5 Nbd7 8.Bd5 Nxd5 9.exd5 Bf5 10.Qf3 Bg7 11.c3 Ne5 12.Qf4 Nxd3+ 0-1

Nakamura has played it a few times, but it seems the treatment Volokitin gave him cured    him of the disease. The point of 2...Nf6 is 3.Qxc5 Nxe4 and black is a bit better.

[FEN ""]
[Event "6. YM"]
[Site "Lausanne SUI"]
[Date "2005.09.19"]
[Round "3.2"]
[White "Nakamura, H"]
[Black "Volokitin, And"]
[Result "0-1"]
[WhiteElo "2660"]
[BlackElo "2671"]
[ECO "B20"]
[EventDate "2005.09.14"]

1.e4 c5 2.Qh5 Nf6 3.Qh4 Nc6 4.Be2 e5 5.d3 Be7 6.Qg3 d5 7.Nd2 O-O 8.c3 b5
9.Nh3 d4 10.c4 Ne8 11.cxb5 Bh4 12.Qf3 Nb4 13.Bd1 f5 14.a3 Nd6 15.axb4 fxe4
16.Qh5 Bxh3 17.g3 Qf6 18.Bb3+ Kh8 19.f3 exf3 20.Kf2 Bg5 21.Nxf3 g6 22.Bxg5
Qf5 23.Qxh3 Qxf3+ 0-1

Edit: weird that the viewer doesn't show headers. That's Nakamura-Volokitin, Lausanne 2005.


Why move the queen’s rook to defend d-file instead of king’s rook? In this position, why is it better to move the queen’s rook to defend the d-file instead of the king’s rook? Moving the king’s rook to the d-file becomes more challenging. Is it important to leave king’s rook behind to support the king? Is control of the f-file more important? I am curious about the logic behind of choosing the queen's rook in such situations.

[FEN "3rr1k1/pp3pbp/1n4p1/4P3/3P2b1/B4N2/P3BPPP/R4RK1 w - - 0 1"]

1. Rad1

White needs to find a way to make use of his extra pawn, because it is hard to see any other plan. His dream would be to play d4-d5-d6, but this is not yet possible because a) d5 is under Blacks control, and b) the Pe5 would hang. Having the Rooks on e1 and d1 would address both of these issues, and that would be a motive to choose Rad1, but there is still play in this position and White needs to be accurate.  Whites K is extremely safe, so that is not a concern. There is no reason to worry about Bxf3. The resulting "weak" pawns do not matter because they cannot be attacked. Best in this situation seems be Bb5 which forces either Bd7 or Nd7, both of which reduce the effectiveness of Blacks blockade. A plausible continuation after 1..Nd7 would be 2. Ng5 threatening Bc4, 2..h6, 3.Ne4 intending Nd6. So Black will have to play ..Bd7, and then White can play Bxd7 and reorganize at leisure. He might consider putting the KR on d1, followed by a Knight move and f4. The QR is then free to occupy the c-file. It is too soon to analyze to a clear conclusion, but I would certainly expect White to win.

This discussion is based on specifics of the particular position, and not on appeal to any general principles. That is almost always the way to go.


At what handicap are humans as good as computer? It is well known that the best chess engines are now far stronger players than the strongest human players.  But is it known what the smallest handicap is that makes them roughly equal?

No scientific studies on this that I know of, but chess.com has hosted some online matches between super GMs (like Nakamura) and top engines in the world (esp. Komodo if I recall correctly).

In these matches, the human GM is given one of the following odds from the starting position:

An extra exchange (so rook for knight).
The engine, playing Black, is missing its f7-pawn.
White gets two extra moves on top of his additional right to go first (I think).

Each of these are approximately +2 for White. So it seems that at the top level for humans and engines, a +2 advantage is needed to ensure rough equality.

Pretty humbling if you think about it. Wait until they perfect machine learning with engines...


Program for determining the type of opening / endgame How can I classify openings or endings of several games?

Is there a program that takes Portable Game Notation (PGN) files as input and outputs that type of opening or type of end game (if any)?

Can a program go further and for example, pin-point who made a mistake where in the openings/endgame?

Scid using stockfish will do this. And on iOS I use the Stockfish app to do this.


Has any chess player ever been banned because of doping? In December 2008, the German magazine Der Spiegel reported on Vassily Ivanchuk's refusal to provide a urine sample for a doping test. This type of refusal is "treated as a positive test result" (according to the article), but FIDE decided that there was no need for a penalty.

I am not aware of other similar stories in chess. So has any professional player ever been temporarily banned from playing because of a positive doping test?

The short answer is "No". The long answer is "Don't be silly!"

About a year ago I asked elsewhere if the English GM Mickey Adams (the only English player at the time comfortably over 2700) had to go through the WADA style rigmarole of informing the chess anti-doping officials of a time and exact location for every day of the year where he could be found if they wanted to test him as required by FIDE's anti-doping policy.

A prominent member of the FIDE Qualification Committee replied "I'm not saying you're wrong, but that's news to be. Where can I find it?"

This 73-page FIDE document - FIDE Anti-Doping Rules based on Wada’s Models of Best Practice for International Federations and the World Anti-Doping Code - from 2015 spells out in painful detail what FIDE's "intentions" are.

When I sent him the link this was his response -  "I think the International-Level part refers only to things that FIDE Anti-Doping can do if they want to and in practice don't, but still worth knowing."

So, at the moment FIDE has a suitable IOC-friendly policy on the books but they are only likely to actually implement it if the vast Olympic money bags are opened for chess.


Formal definition of corresponding squares For (endgame) training purposes, I would like to write a python program (using python chess) that generates all pairs of corresponding squares in a pawn endgame. Following the definition from Dvoretsky's Endgame Manual, I define corresponding squares as squares of reciprocal zugzwang.
This definition, however, does not seem to formalize corresponding squares.

Suppose we have access to a scoring function s that returns, for any position p, a score s(p) from a totally ordered domain S of scores.
The maximal score means that White wins, and the minimal score means that Black wins.
The simplest scoring domain is the ordered set {-1,0,1}, where -1 is a win for Black, 0 is a draw, and 1 is a win for White.

Given such a scoring function, I now define a reciprocal zugzwang as a position p such that s(p_w) < s(p_b), where p_w and p_b are the positions derived from p wherein White resp. Black is to move.
This definition states that White would prefer to Black to move, and vice versa.

However, this definition of reciprocal zugzwang does not yield the usual notion of corresponding squares. For example, consider the Fahrni - Alapin position.
If Black is to move, White can win easily.
White is to move can secure a win by means of triangulation.
Nevertheless, Dvoretsky claims that the kings are placed on corresponding squares.

What would be a sensible formal definition of corresponding squares?

Two squares A and B such that after the attacker (player going for the win) moves to square A the defender must move to square B to hold the position (at least for the moment).

This doesn't say that the attacker won't still win the game down the road (with objective play from both sides). But to prevent an immediate win the defender must go to B after the attacker goes to A.


THE longest problem ever (much longer than the mere 549 mover...) The "Fireside Book of Chess" by I. Chernev and F. Reinfeld includes the following diagram
[fen "3nk3/3NN3/3PP3/3BB3/3PP3/3PP3/3PP3/2RQKR2 w - - 0 1"]

Composed by J.N. Babson for Brentano's Chess Monthly in 1882. Mate on
the 1220th move, after compelling Black to make three successive and
complete Knight's tours.

(Note that there is a mate in one. The problem asks for something more specific.)
Facts:

Babson is a real composer, famous for long mate problems.
Brentano's Chess Monthly was a real publication from 1880 to 1882, and Babson did have problems published there.
A FIDE page that lists people with FIDE titles has a biographical sketch of Babson citing a 1220 move problem, and a 1990 move problem on a 10x10 board.

Issues:

I can't find any reference to this problem on the web, other than the above mentioned book.
Nobody ever mentions any problem with this many moves... anywhere!
A knight tour is the motion of a knight through all the board squares. Three of these would mean only 192 moves.

So here are my questions:

Is the problem for real?
How should one interpret the knight tour condition? Probably the knight will capture most of the central pieces, but do the other pieces have to move aside to let the knight through?
What is the solution?
Why is this not more widely known?

After some searching, it turns out that this monster is very much a real chess problem. The official name for it is  "The Obelisk."
The earliest known reference I have found is from February of 1882, mere weeks after its publication. Bizarrely, it comes from an Australian magazine. The site I found it on is trove.nla.gov.au.
It appears in 1882, February 25th edition of the South Australian Weekly Chronicle, published in Adelaide, on page 25. It is part of an overall review of Brentano's January 1882 issue.
Here is a clipping of the relevant section to read for yourself.

I also found mention of it in "American Chess Review, Volume 1, Issues 1-6" (readable on Google books) from 1886, just four years after the original publication in Brentano's Chess Monthly.
The information is given in the middle of the page. The position itself is given near the end of the page in descriptive notation (link to Wikipedia](https://en.wikipedia.org/wiki/Descriptive_notation)). Note that the "S" is German notation for the knight; it was semi-standard back then.

Here are later sources.

Chess Review 1936, issue 37 page 17; viewable online in the US Chess Federation online archive
Curious Chess Facts, by Irving Chernev, 1937
Wonders and Curiosities of Chess, page 205, by Irving Chernev, 1974
The Complete Chess Addict, by Mike Fox & Richard James, 1987
The Even More Complete Chess Addict, by Mike Fox & Richard James, 1994

Unsurpingsly, there is no solution given anywhere at all. The reason for this is that the magazine ceased publication soon after the mate in 1220 printed. Thus, another edition with the solution was never made.
As for how to interpret the stipulation, I believe it is very simple. Wite forces the Black knight to visit each and every square three times. Then White gives checkmates. Most of the moves come from White's piece dancing around in order to do said forcing. If anyone is crazy to try and solve it, they will surely find a much shorter solution than whatever Otto Blathy had in mind.


1900 rating with no progress I have been around 1700-1900 rating (glicko 2) for a while. I have been losing on tactics when there aren't many pieces left.(mid-end game) My positional thinking is alright, and my endgame skills are alright. I play king's pawn with white and caro-cann + queen's indian for black. Also I have big strikes. On a good day I can win 5 in a row, on a bad day I lose 5 in a row. How can I improve my rating?

Do tactics regularly (possibly every day). Below 2000 rating is probably the best thing you can do, especially if you have a weak point there.

Ideally you want to practice for ~20-60 minutes (depending on how committed you want to be) on problems that do NOT give away the theme of the tactic involved (e.g. "exchange sacrifice", "overload", etc).

Another thing you can do is to review your games, and if you lose due to tactics try and figure out which was the best response to parry that blow. In any case reviewing your own games is the key to improve (first review them on your own, and once you're finished go through them with an engine).

Finally, I think you might want to watch other people playing, especially ranked 200-400 higher than you, and then review those games as well. I find it very useful because I usually understand the reasoning behind moves I didn't think about during my own games.


Can a human defeat an engine in a 10-game match if he is given the White pieces and draw odds in every game? What would happen in a 10-game match between one of the strongest human player (Carlsen, Caruana, Aronian, Kramnik or Anand) and one of the strongest engine (Komodo, Stockfish or Houdini), but with the following two conditions:

The human always has the White pieces in every single game.
The human is given draw odds: a draw is counted as a White win (i.e. in the advent of a draw White gets 1 point and Black gets 0 point).

The games are played at classical time control: 120 minutes for the first 40 moves, 60 minutes for the next 20 moves and then 15 minutes for the rest of the game with an increment of 30 seconds per move starting after move 61 has been made.

The engine is run on a powerful computer, gets 7-piece Lomonosov endgame tablebases, has permanent brain (ponder) on, and has a big opening book designed to avoid getting into drawish positions.

In contrast to Rauan Sagit, I'm going to offer some reasons I think any human should (assuming they don't get lucky and play some computer-level games themselves) lose such a match.

Elo differential: As of Nov.15, 2014, the highest-ranked engine on CCRL 40/40 is Komodo with an Elo of 3303 on relatively modest hardware of an Athlon 64 X2 4600+ 2.4 GHz (Engine ratings were initially based on human ones, but you could debate how relevant it is to compare the two. We have no other metrics, though, so I'm going with this). The all time peak rating was Carlsen's 2882 - let's use him as our example and assume he is able to play consistently at a 2882 rating level. This is a differential of 421, and the central observation of the Elo rating system is that a rating difference of 400 points should correlate to a 95% probability of the higher rated player winning (not counting the possibility of draws). Top GM games draw around 50% of the time, meaning that even if this rate stays the same, Carlsen will be fighting for draws with no practical possibility to push for a win. This means that, at best, you would be expecting him to stand a chance of just winning the match with him playing at a peak level consistently throughout the match.
Time control: If the time control is short, humans are likely to blunder when at best computers will make sub-optimal positional choices. If the games are long, it becomes very hard for the human player to remain consistent until the end of the match.
The engine (assuming the people setting it up actually want it to win) would have it's 'contempt for draws' set really high, meaning it would keep pushing on until the human cracked.
The psychology of such a match (assuming that there is enough of a prize/prestige for the human to be taking it seriously) can be really taxing on the human player. Kasparov-Deep Blue were 6-game matches and Kasparov was finding to hard to maintain his mindset and mental stamina well before the end of these. Of course, there were other factors at play at the time, but a 10-game classical control match is very taxing.

I'd also point out that Rauan's last paragraph suggest a modification that would likely make it too easy for a human player to win. keeping the computer's calculated advantage relatively low after 30 moves should not be too difficult with appropriate opening choices. I think a better adjustment would be that if the score is 0.00 +- 0.05 for at least 5 ply and the human offers a draw, the machine must accept. Either that, or make the match take place over a long period of time, with one game every 3 months or so (in amongst other tournaments) to prevent fatigue.


Can the King be put in Check by a piece that cannot move? I am playing a game at the moment and I want to know if the King can take a piece that is being protected by another piece... that cannot move.

Why can't the other, protecting, piece move? Because it would put the other King in check.

In other words: Can the Black King take the White Rook?

No, the black king cannot capture the rook in the position. The simple explanation is that the white knight will capture your king before your rook captures your opponents king. Personally, chess should not have rules such as check and checkmate. The aim of the game should be to capture the king, not checkmate the king. I speculate that these rules of checking and checkmate was formed by etiquette anyways since even in Xiang qi where the object is to capture the "king," you still say check, and I learn that it was a convention of etiquette. .


Is it forbidden to laugh when playing in a chess tournament? I have read this, but it still hasn’t filled my brain yet. When I play chess, sometimes I'm often laughing and putting some pressure on my opponent. Is it forbidden in legal game? Is there a rule about it?

The FIDE Laws of Chess:

  11.5 It is forbidden to distract or annoy the opponent in any manner whatsoever. This includes unreasonable claims, unreasonable offers of a draw or the introduction of a source of noise into the playing area.

Distracting or annoying the opponent in any manner (other than making good moves!) is forbidden, and making noise is forbidden. So laughing in order to give pressure to your opponent is forbidden.


Is short castling dangerous in Bughouse? When I play Bughouse, I see that, every single time after a castling, petty sacrifices can easily be break the wall that surrounds the king,Therefore, is it really worth castling, especially short castling, in Bughouse?

Tempo is king in bug house for castling. By definition, unless your castle makes a immediate threat somehow, you have lost 1 tempo. In other words, it is at least one more move until you improve or gain position to attack.
If it takes your op 2 or more moves to make a threat, then you have a +1 tempo gain and it might be worth it.
If you are under immediate threats, then this might be good also if it forces a 1 tempo action for op to retarget.

If your partner's board is timelocked, then it may be of long term value to castle. Depends on how many troops are waiting to crash down. Your board becomes more like a normal yet rapid chess game


Make chess engine play a particular position I want to be able to train my mating skills by making a chess engine play positions that others have resigned from.  Is there a way to make a chess engine play a particular position?  I am using stockfish and scid vs pc at the moment.

In Scid vs PC got to Edit > Setup Board. Here you can setup the board with a particular position, set side to move and castling flags. Easier is if you have a FEN of the position, you could just paste this and use it directly. Click OK once you are done to get the position on the main board.

Now navigate to Play > Computer-UciEngine > Choose your stockfish engine, Check "Start from current position", Set desired time control and click "Play".


Common sacrifice themes in attacks? What are common sacrifical themes in mating attacks? For example, the Greek Bishop Sacrifice.

Not exactly sure what you're after with that question, but here's something to at least open the ground a little.
The "Greek Gift" I think is more a name for a particular sacrifice than a theme. It employs a couple of themes, e.g., line clearance and decoy -- line clearance opens a hole in the castled position for other pieces to use for attacks, and decoy brings the enemy king to a square where it can more easily be attacked. Another famous sacrifice using those themes is Lasker-Bauer (Lasker's double bishop sacrifice).
There are numerous resources covering tactical themes, going back to Spielmann's "The Art of Sacrifice In Chess" but a couple of the best resources for mating themes and patterns are Renaud & Kahn's "Art Of The Checkmate" and Vukovic's "The Art of Attack in Chess" (of the two I'd prefer the latter only because it covers more than just checkmates, but all three books are well worth the time to study them).
In Vukovic's book, chapters 4 & 5 deal in general with your question of checkmating themes. As for the "Greek Gift" itself, he spends chapter 6 specifically on that sacrifice. Eugene Znosko-Borovsky in "The Art of Chess Combination" spends a chapter on it (and another on Lasker's double-bishop sacrifice) and Former US Correspondence Champion Jon Edwards devoted an entire book to it (Sacking The Citadel).


Is the king actually in check if the attacking piece cannot be moved? Black was in a position to take a white bishop with the king.  The white bishop was protected by a white knight.  However, if the white knight was moved it would expose the white king to the black queen.

Thus, is the king actually in check if the attacking piece (white knight) cannot be moved?
Or,
Can the king move into check if the attacking piece (white knight) cannot move?

Thank you.

Still considered in check. FIDE handbook from the WCF website.

  3.9
  The king is said to be 'in check' if it is attacked by one or more of the opponent's pieces, even if such pieces are constrained from moving to that square because they would then leave or place their own king in check. No piece can be moved that will either expose the king of the same colour to check or leave that king in check.


Why do players think after they have made a plan? I have seen many live competitions from top GMs, and I can usually see one thinking 15 minutes straight, then doing a tactical move. After some thinking from the other player, he does the main move, the one the engines say it is the best, and probably was considered by the first GM. I keep seeing GMs thinking, spending more time, even if the opponent plays what they wanted. Double checking might be it, but still, isn't it valuable time spent on checking an already checked position?

I had the same thought myself. For a couple tournaments, I started playing lines which I had calculated out with about 10 seconds of thought on each move. My results were terrible.

The reason, I think, is that the extra move being played on the board gives you quite a bit of added calculation power. I now take more time on the moves following a long think and I frequently encounter errors in my previous analysis, which I either have to find fixes for or find a new move.


Implement a chess app for Android with Stockfish I want to implement a chess app for Android with Stockfish.

I downloaded the Stockfish binary source code, but I don't know how to use engine

Please tell me how to use Stockfish engine for programming.

@Glorfindel is absolutely correct (+1). To get you started, do this:

Read UCI specification (http://wbec-ridderkerk.nl/html/UCIProtocol.html)
Download Droidfish source and check how it interacts with the engine
Learn how to compile Stockfish with JNI
Create an empty Android project. Send the engine isready. Do you get anything back from Stockfish?


Chess Engines that have "Deep" in their names? Why is it that some chess engines have the word deep in their names? It does seem to be a common trend, but not one that is universal.

It used to be the case that the "Deep" specified the multiprocessor version. At least for Fritz, Shredder and so on, the "old" engines. But I guess nowadays every engine is a multi processor engine …

This naming trend was surely started by Deep Thought, the first seriously strong IBM chess machine. And of course Deep Thought was named after the famous computer from the hitchhiker's guide to the galaxy.


How do you use Fritztrainer DVD with Fritz 15? I recently just got The Modern Grand Prix Attack Fritztrainer DVD, and I only have Fritz 15. I put in the activation code and can see the video, but the problem is that the chess board next to the video doesn't move. Hence, I can't see the pieces move when the IM goes over the games and variations. When I remove the DVD and put in the Fritz 15 disc, Fritz 15 works, but the Fritztrainer isn't there anymore. I couldn't find any customer service phone number. How do I get the Fritztrainer to work?

The Chessbase support site describes the process of viewing chess media files (or, what many call Fritz Trainer videos) as follows:

  If you have the lecture on a CD or DVD, [...] then
  you simply open a file using "File – Open – Chess Media File". The
  program will open a chess media window and you can sit back and watch
  the game.

Here is a screencap of my doing this process for the Fritz Trainer, Fit for the French by GM Viktor Bologan:

Note that very often the first video in a Fritz Trainer will be just the GM talking and giving you an overview. Then, you won't see any pieces moving (e.g., GM Garry Kasparov on the Queen's Gambit rapidly discusses lines without showing them on the board).

Finally, if you're opening the video files using these instructions and they don't show pieces moving when they're supposed to, you may have gotten your files from a disreputable source that has stripped them of their proprietary Chessbase metadata. In that case, you'll want to try to get a refund or download the Fritz Trainer from Chessbase.


How should I analyse my game to get better? I've been playing chess for a while, but very casually.  I just joined a chess club and played my first tournament game.  Not having used a chess clock before, or ever having had to record my moves made things interesting!

I really want to get better and I've heard I should be analyzing my games.  Other than stepping through them and figuring out if I should have done something differently (given I lost, probably), is there something specific I should be doing?

This is my game from tonight, any ideas/analysis would be very welcome.

[fen ""]
1. e4 c5
2. d3 Nc6
3. Nf3 e5
4. Nbd2 Nf6
5. c4 Be7
6. Nb3 O-O
7. Be3 d6
8. h4 h6
9. Qd2 Ng4
10. O-O-O Nxe3
11. fxe3 a6
12. d4 exd4
13. exd4 cxd4
14. Nfxd4 Ne5
15. Qf4 Qc7
16. Nd2 b5
17. b3 bxc4
18. Bxc4 Nd3+
19. Kb1 Nxf4
20. g3 Ne6
21. Nd2f3 Rb8
22. Rc1 Qa7
23. Nc6 Qe3
24. Nxe7+ Kh8
25. Rhf1 Qxe4+ {I realized this was a mistake as soon as I made it}
26. Rc2 Nd4
27. Ne1 Nxc2
28. Nxc2 Qxc4
29. Ng6+ fxg6
30. Rxf8+ Kh7
31. Kc1 Qd3
32. Rd8 Bf5
33. Ne1 Qb1+
34. Kd2 Rxd8 {i resign}

Opening

I feel that you are getting lost in the English Botvinnik system, seeing as you form the Botvinnik pawn triangle (c4-d3-e4) but then your piece placement is off (e.g. O-O-O instead of O-O). I suggest you visit my answer to Suggest a line for a player who does not want to be dragged into the Sicilian for more information.

Also, try not to move the same piece multiple times in the opening, as 6. Nb3 isn't constructive. I would try 6. Be2 and 7. O-O with a safe but cramped game.

Material

You concede the bishop pair (half a pawn) with 9. Qd2 instead of 9. Qc2.

The move 15. Qf4 is the start of your tactical woes. This square should set off alarm bells because of both the potential for a knight fork and pin (...Bg5 may become playable). I would have looked at 15. Kb1.

Tournament etiquette

Comfortably using notation and the clock comes with practice, but I don't understand why you carried on playing after 18...Nd3+.


Can one simulate a top GM strength? I would like to know roughly if a top GM could win a given position against a top engine.

Is there a way of adjusting an engine's settings to simulate the strength of a top GM in order to make it play against a full specs engine? If so, which engines allow for these adjustments?

Ubisoft's Chessmaster: Grandmaster edition allows you to set games between artificial players. One is the engine itself and there are simulated top players, e.g. Anand. You can set the games from the starting position or from a set position.

Please see my answer to Looking for a good chess program with a couple of features for relevant screenshots.


Replacement for pgnscid Last Scid versions come without pgnscid shipped with it. That happens since version 4.6.0, when it was removed because it was stated as obsolete, according to changelog.

I guess that if pgnscid is now obsolete must be because another executable can be used to do what the former did, a command line utility to convert a pgn file into a scid database, but I'm not able to find out how to do it with the other executables packed with Scid.

Does anybody have a clue on which is pgnscid replacement?

pgnscid does not have a replacement. Instead, it is expected that you import the pgn file within a SCID database.


What ELO is it good to learn and play the Kings Indian Defense OTB? I am roughly 1400 USCF and when I play against 1. d4, I tend to avoid the theoretical stuff (Benoni, KID) and defenses such as the Nimzo and QID (mostly anything hypermodern). So I stick with the classical 1... d5 defenses mostly. But, as I am becoming a better chess player I am looking towards other openings; I have played the KID over some casual games and of all of the other d4 defenses, I play the KID intuitively pretty well.

However, what is making me reluctant of it is defending against the Four pawns attack, Saemisch, and Averbakh lines (or anything where white plays a early Bg5) are a bit annoying. But I enjoy playing against the classical lines.

What would be a good choice?

Elo points don't matter. Just play what opening you feel comfortable with most. If you play it well intuitively, then go ahead.


Significance / Plan behind the move White's last move was Ra2. I was to curious
to know the plan behind or any strategical / tactical significance
behind that move.

Ra2 moves the rook off the diagonal of the g7 bishop thereby preempting any tactical tricks that might occur later. It is better than Rb1 since then Qa5 would embarrass the bishop on a3.

It also leaves b1 free for the queen later when white wants to exert more pressure down the h1-a8 diagonal of his g2 bishop against b7 and c6. Black has a passed a pawn and white must generate pressure in this area in the medium term if the pawn is not to win the game for black in the long term.


Is it acceptable to pair a player with the same colour three times in a row? A few months before an official national tournament is held, an announcement is published, which contains information about specific rules (e.g., no draw offers until the 30th move), etc. One thing that caught my attention was that a player can't have the same colour for 3 consecutive rounds.
Yet, in the last round, I played Black and my opponent White. After the end of the game, I realize that my opponent had taken White 3 times in a row. Swapping colours was also impossible since I was Black in the last 2 rounds.
Can the result actually be changed? Or should the game be replayed?
As I am not an arbiter, I'd also like to ask whether there is an option in Swiss Manager (the pairing program used) not to allow players to get the same color 3 times in a row?

Lodging an appeal also came to mind that time. However, can the result
  actually be changed?

No. Only in extreme cases such as cheating can the result be changed.

  Or should the game be replayed?

No. There is no reason why the game should be replayed.

  In addition, as I am not an arbiter, is there an option in Swiss
  Manager (the pairing program which was used to make the pairings) not
  to allow players get the same color 3 times continuously?

Swiss Manager uses the JaVaFo pairing engine written by FIDE. The pairing engine implements the FIDE defined pairing rules. As far as I know (I am a FIDE arbiter) the only pairing rule that can be overridden is the one which says that a player who has already had a voluntary bye can also be given a compulsory bye in a later round given an odd number of players. In my experience this is never done.

  In the last round, I played with Black and my opponent with White.

  After the game, which I unfortunately lost, due to the lack of opening
  preparation, I realized that my opponent had taken White 3 times in
  the 3 last rounds. Playing with opposite colours was also impossible,
  since I had White 2 times continuously. In addition, I had played with
  most of the players which were up to the 10th position, so I couldn't
  find anyone else to play - maybe this is an exception?

In the FIDE Handbook the rules for Swiss pairing are given in the section Basic rules for Swiss Systems.

Your case is covered by these two rules.

  f For each player the difference between the number of black and the
  number of white games shall not be greater than 2 or less than –2.
  Each system may have exceptions to this rule in the last round of a tournament.

  g No player shall receive the same colour three times in a row.
  Each system may have exceptions to this rule in the last round of a tournament.

In the last round of a tournament the requirement to allow the highest placed players to play each other in the interests of having clear winners and major places decided fairly takes precedence over most of the other rules. The rule which says that two players who have already played in an earlier round cannot be paired against each other again takes precedence over all other rules and cannot be broken.


Introduction to the Sicilian I am trying to work on my openings and start playing the Sicilian as a response to 1. e4 but I am slightly overwhelmed by the huge amounts of resources available. I am rated around 1850 FIDE and I mainly play the French as a response to 1. e4 and the Gruenfeld as a response to 1. d4.

What would be a good resource for a player of my level to get used to the Sicilian? My goal is not to get an extensive knowledge of the opening, I just want to play/become familiar with a few variations, i.e. the Najdorf, the Sveshnikov and the 3. Bb5+ variation after d6

There's no known recipe that works for everyone for how to approach the Sicilian (or any new opening) as a newcomer to the opening, but it definitely helps if you concretize your target even more than what you've described in the OP. To do that, you might find the following general considerations helpful, specially given that Sicilian is a vast and rich system in opening theory:

Mindset and approach:

Find players whose approach to employing the Sicilian suits your style, in terms of: the type of play (closed, open, sharp), depth of needed theory, whether it's midgame or endgame oriented etc, and study their games (e.g. Kasparov's games).
When studying such games, for at least the first 10 moves, constantly ask yourself what the purpose of each move is in theory (for the move order you're trying to learn), and if you find the point of a move goes over your head, follow through a few variations with the engine with and without that move and see what repercussions it has on the ensuing variations.
Even more important than understanding specific moves, try to learn what the underlying plan of the particular Sicilian variation you're studying is, this really cannot be emphasized enough. Once you know what the line aims to achieve from a strategic point of view (e.g. is it to create an isolated pawn structure, is it to establish a permanent knight post in the centre, is it to trade bishops or keep bishop pair, etc), making sense of the moves and the ensuing play becomes much easier to grasp.
Once your particular type of Sicilian system (Kan, Sveshnikov, Dragon, Taimanov, etc) is decided, then you can focus your resources on that system and your search becomes much more meaningful.
Once you get a grip of the basic ideas behind the system of choice, start carving your own version of the system, personalize it according to the kinds of positions you feel comfortable playing and where your skills lie (middlegame, tactical, strategic, endgame player etc), and in that regard learn the relevant transpositions, while always checking your new ideas with an engine.
Keep practicing your developed system, 1-2 two blitz games won't cut it, you need to play many many games until the concepts start to sink in and you form a good intuition for the opening. Keep analysing each game irrespective of the outcome, go back to the opening stage and find improvements.
A training exercise that is often quite helpful is to: play the opening lines you're trying to master in your head without any visual aid (board, phone) against yourself, e.g. when on a commute or during a nice walk. When playing blindfolded against yourself, saying the moves helps a lot to remember the position (that is, literally saying to yourself Nc3, d5, etc).

Tools for the learning process:

To keep a clear note of the ideas you learn along the way for each line and move order, create a study on lichess and fill it up with annotations and arrows, and go over these studies to review and brush up on what you've learnt every now and then.
Similarly, create a study for the personalized system you start building for yourself. These studies can be made private, and of course they will always be work in progress as you will regularly update them with any new finding. For more on lichess studies see also this post.
To explore opening lines and try new ideas, use the opening explorer on lichess (and many other available ones online) with the Stockfish cloud engine active in the background, play through the lines and cross check your ideas with the engine.
There exists various video series on the Sicilian, e.g. on chess24 see here (for instance the Taimanov one by Robin van Kampen has become quite well reviewed).
Other online resources: Check out the content on various chess youtube channels, e.g. ChessExplained or ChessNetwork, they provide very clear commentary as they play or analyse games, and they both frequently play the Sicilian too. And of course the wonderful lectures by Yasser Seirawan, e.g. on the Pin variation or the Accelerated Dragon.
Last but not least, books, books, books! They still remain the best resources in chess. There are plenty written on the Sicilian too (e.g. see the recommendations by Chris), find one author and book level that matches your taste and get started! Reading chess books is almost always an interactive process, where either you're pausing to calculate something blindfolded, or setting up a board and going through some variation discussed in the book. Generally, they're not read cover to cover, and specially if they are extensively covering something, such as Endgames in chess, or Pawn structures, you will be jumping around the book frequently to read up on the bits that currently are relevant for your improvement. Remember that there's no one book that is the best, these things are always subjective to our preferences, so try to explore and find one that you like and read up patiently ;)


Where can I find a list of chess games (or PGN file) for games less than X number of moves (specifically 12 moves)? I was reading a book on chess where the author suggested that a good way to practice getting good at the opening is look at miniature games (less than 12 moves specifically) played, that have led to checkmate.  The implication is that these games must have involved serious blunders to end so early, and so that an amateur can learn about vulnerabilities and how to take advantage of them, by reviewing or playing through these games.

I have looked up books on miniature games, but first they're often longer than 12 moves, and second, usually it's only the famous ones that involve brilliant tactics that are mentioned.  I want a much bigger list of these games that I can play through.  Appreciate any help.

pgn-extract can extract games from a pgn file based on the number of moves. The -bu12 flag would give you games of 12 moves and less. There are various databases which you can download for free, see this link

12 moves are really short games, you might want to extend that limit a bit and probably you also want to exclude games that end in draw.

Also IMO  solving general tactics puzzles is very useful for a beginner.


Advice for breaking Lichess's 2000 rating mark Although I have known the rules of chess since I was little, I only actually started playing it in May or June 2019, so about 6 or 7 months ago. When I started I had a Lichess classical rating of around 1100 (at my lowest I got to 1000!). With some peaks and bad moments, I did manage to increase my rating quite consistently over the months, and I have recently gotten to 1900. This was very satisfactory for me, since I really studied hours per day and worked very hard in order to improve.

Nevertheless, I find that I can't really move on now! I got stuck on 1900. This happened to me before at a 1500 rating; at that point, after being stuck for weeks, I studied Nimzovich's "My System", which was what allowed me to break the 1600 rating mark and continue to improve. I wonder if there is perhaps a book, a practice routine or something that could help me, like Nimzovich did when I was stuck in 1500, to 'step up' and break the 2000 rating mark.

I do know that what I most need to improve is my endgame (and I'm working on it and improving little by little). Does anybody experienced something like this? If so, what books, routines or approaches to the game helped to break the curse?

"PhishMaster's Complete Guide To Improvement": What to study, and how.

Every player has times where they "plateau", and have trouble moving on, but they usually get past it eventually if they are continuing to study. Sometimes, it is a matter of patience.

Here is a set of comprehensive answers to questions I previously gave in various chunks, that are now combined, and will include how to break 2000.

First, this outline is more for the average player, who still may be very decent, but is not likely to be become a professional.

Beginners up to 1800, it is mostly about tactics: Tactics, tactics, and more tactics. I have found that even players, who are 2100, are not as strong at tactics as they think they are. I also found that having a very strong dose of endgames, even when I got my first rating of 1036 USCF back in 1980, has stuck with me all the way through being a Master. I still love Fine's "Basic Chess Endings" (any mistakes in it as far overshadowed by the principles that it puts forth).

For tactics, I actually recommend starting with Reinfeld's "1001 Brilliant Ways to Checkmate", and then "1001 Winning Chess Sacrifices and Combinations". I firmly believe in good groupings of themes in the beginning, rather than sites that totally randomize your study. I also firmly believe in immersion, in other words, doing a lot in a short period of time. It just sticks better as far as I am concerned.

I recommend doing 50 per day, spending no more than two minutes per move on each problem. In pencil, write down next to the problem how easy you found it on a scale of 1-5 because you will do these books multiple times. That immersion method has worked very well for me. I took a friend, who was about 38 at the time, from 1000 to 1850 on ICC in three months following this method.

Around 1800, people start getting more clued in on positional play, and start picking up more on that. I still love Ludek Pachman's trilogy: "Complete Chess Strategy". That was the first time I started to see real plans enter into my games, and I still credit that trilogy with making me a Master. For the first time, I started to really grasp pawn play.

Also, around 1800, I also think that players need to understand HOW to play opening pawn structures instead of focusing on memorizing openings that when their opponent deviates, they are lost and on their own. For this, books like Soltis' "Pawn Structure Chess" (a really bad book if you are looking at it with a computer, but the underlying principles are very strong), and Mauricio Flores Ríos' book "Chess Structures: A Grandmaster Guide" is a fantastic book that expounds upon what was in the Soltis book, and does it a lot better, but also at a higher level.

Starting at 2000, assuming you have a shot at 2200 and higher, you are going to start needing specific openings, and memorization as you face stronger competition. All along, you should have been still studying more and more endgame material as you will also need that when you face "monsters".

Over 2200, you are talking about in-depth refinement of what you have learned. A lot of people buy the Dvoretsky books before they are ready, and now is the time that you are just getting started to be ready for those. They will help with small details, and a lot of it above 2200 is analyzing better and better, so not only will his books refined and expand your knowledge, they are hand-picked difficult problems that need a lot of deep analysis.

Once at 2400, if you have not already had a professional coach, you probably will need one to really gain a lot more strength. In addition, if you have a kid, who is super talented, and clearly going places, it is also probably a good idea for them to have a professional coach at a lower rating, and younger age to get the most benefit.

Here is a list of areas of study, and what to read while doing them.

To help with basic visualization, read these books without a board, including sub-variations. If you are not sure how well you did, then put them on a board, and compare the board to your mind’s eye. In the beginning, I expect that you will have more on the board than not.
a.  “Combinations, the Heart of Chess” by Irving Chernev
b.  “1000 Best Short Games of Chess” by Irving Chernev (The games start short at only four moves, and gradually work up to 25 moves.)
c.  After these, you will still probably need work on visualization, so pick fun combination books to do in your head, concentrating on visualizing the final position rather than finding the solution. Solutions are in the next group.
To help with both basic visualization and tactical vision, do at least 25 problems per day, but preferably 50, spending no more than two minutes per move before looking at the answer. You will repeat these books at least twice over time. This alone, is why most players never get stronger…they drop pieces.
a.  “1001 Brilliant Ways to Checkmate”, 21st Century Edition by Fred Reinfeld
b.  “1001 Winning Chess Sacrifices and Combinations”, 21st Century Edition by Fred Reinfeld
c.  Continue with any of the multitude of tactics books or trainers out there doing as many as you can each day.
Endgame. Play all of these out on a board, not in your head.
a.  “100 Endgames You Must Know: Vital Lessons for Every Chess Player” by Jesus de la Villa (Try to memorize this book, especially rook endgames since they are the most common.)
b.  “The 100 Endgames You Must Know Workbook: Practical Endgame Exercises for Every Chess Player” by Jesus de la Villa
c.  “Basic Chess Endings” by Ruben Fine (Although there are mistakes that have been show by both humans and computers over the years, this book shows more about the plans and what you are striving for than most endgames books. Read all the sub-endgames since they reinforce the main endgames.
d.  “Dvoretsky’s Endgame Manual” (aka DEM. This is THE single greatest chess book ever written, in my opinion, and it is very advanced, but if you have reasonably mastered the above two books, this is the next step).
e.  “Tragicomedy in the Endgame: Instructive Mistakes of the Masters” by Mark Dvoretsky (This is, in essence, the workbook for DEM, giving practical positions of the material in DEM.)
Pawn Structures, and how to play chess, in general. A lot of chess is “what pawn break am I looking for, and how do I accomplish it?” These answer that in depth.
a.  “Complete Chess Strategy” volumes 1,2 and 3 by Ludek Pachman. (This teaches about many basic plans, and what you are striving for with your pieces and pawns, especially. THIS is what made me a master.)
b.  “Pawn Structure Chess” by Andy Soltis. (This extends the above to specific opening structures.)
c.  “Chess Structures: A Grandmaster Guide” by Mauricio Flores Rios (This is an extension of “Pawn Structure Chess”, and is deeper, and covers more structures. It is outstanding especially if you have already covered “Complete Chess Strategy”.)
Positional Chess. Play these out on a board and you will start to get a better feel for evaluating positions correctly.
a.  “Positional Chess Handbook” by Israel Gelfer (The quality of the printing in this book is not very good, but the content is excellent.)
b.  “Your Kingdom For My Horse” by Andy Soltis (This is all about exchanging, a little-covered, but incredibly important topic in chess. Frankly, Soltis is a LAZY writer, and when you read his books with a program running, you will find ALL KINDS of mistakes, but the prose, and general principles he is teaching are still valid, and in this case, hard to find in any other book. (There is a Russian-only book called "Encyclopedia of Exchanges" if you are capable of reading it.)

You will note that unlike the backpack of a typical 1200-player, there is not a single opening book listed here. That is because you are learning HOW to play chess, rather than memorizing lines that you get to the end of, and have no idea why you are there, or why it is good or bad. Most of your opponents, until you get to 2200, won’t know much about book, and you will both be on your own early on, so the one, who understands what you should be trying for, and who does not lose his pieces (tactics), will win the game most of the time.

In general, read the above list in order within any category, but you should have the visualization, tactics, endgame, and pawn structures categories all going at one time. As you start to really understand the structures more, then add in the last, “positional chess” category.


Pawn promotion strategy Why is it so important to KEEP a pawn from promoting if you have a piece situated so that when the pawn promotes your next move can be to capture it? Is this a matter of tempo? Frankly, once the pawn has reached the seventh rank why go through so much effort just to protect it? I guess I am new at this.

Usually, there's a piece behind that pawn that supports its promotion. Then you're eager to stop the promotion otherwise you'll have to give up your piece for the promoted queen.

If the pawn isn't supported, then the reason for blockade might be prevention of some tactics that could be related to a sacrifice of that pawn.

Aron Nimzowitsch once said:

  The passed Pawn is a criminal, who should be kept under lock and key.


Daily Strategy Traing There are many websites (such as chess.com and 365chess.com) which allow even a free account holder to practise a certain number of chess puzzles on a daily basis. However, I feel that most puzzles are about tactics instead of strategy, such as winning a piece, forcing checkmate, etc. Am wondering if there are (preferably free) online resources that allows one to daily train strategy (such as how to improve your position in a silent game, or create a weakness for your opponent) which does not necessarily resulting in immediate winning of material or checkmating. Any recommendation will be greatly appreciated.

It is relatively easy for these websites to generate many thousands of tactical exercises: they run an engine over a corpus of games (for example, games played on the site itself) to look for blunders, and then turn the punishment of the blunder into a tactics puzzle (usually after additional filtering for example to choose only positions where there is only one move that is clearly best). They don't even need to worry about grading the puzzles for difficulty, because they determine that empirically after the fact, based on the ratings of the users who are able to solve the puzzle or not. The leave it to users to flag dubious machine-selected exercises for review.

The same is not true for strategy puzzles, since strategy is not so clearcut that you could let an engine search for strategically interesting positions. Therefore, strategy puzzles need to be laboriously created by experts. I know chess.com does have a "lessons" section, but you need to be a paid subscriber if you want unlimited access. Many of the lessons are about strategy, for example Roots of Positional Understanding by IM Jeremy Silman has 300 hundred brief "challenges" which you could use as daily puzzles for a while.


Setting up the knights When playing chess on a physical board, which way should the knights face? Sideways (as in chess diagrams) or straight ahead? If there is nothing in the rules about this, how do the professionals usually set up their knights?

There is nothing in the rules about this.

The way that grandmasters set up their knights varies from person to person.

Here is an image from the world chess championship:

Carlsen has placed his knights facing each other, and Caruana has positioned his knights facing forwards.


Collecting principal variations during search and using them in ordering? In an Alpha Beta search in that utilizes a Negamax framework, how does one collect principal variations to use in move ordering, and how does one use them, without using a transposition table?

Additionally, would it be different in a principal variation search, and do we collect and store important moves for quiescence search too? Please provide a code example.

In an Alpha Beta search in that utilizes a Negamax framework, how does one collect principal variations to use in move ordering

Every strong modern chess engine which uses alpha-beta search uses a transposition table to store the PV move for ordering. If you are writing a chess engine, you should this high-performance, now ubiquitous technique.

  and how does one use them, without using a transposition table?

There are various approaches to storing the principal variation which are commonly used alongside a transposition table. The most popular of these is a triangular PV table. The Chess Programming Wiki has a page on this, which includes code examples as you requested.

  Additionally, would it be different in a principal variation search

No. Move ordering can be implemented in the same way for both pure alpha-beta and for PVS. The only difference is the way in which the ordered moves are searched.

  and do we collect and store important moves for quiescence search too?

No. Standard techniques used to order captures are sufficient in quiescence search (namely, MVV/LVA and Static Exchange Evaluation). The move stored in the transposition table may not be a capture, so it is unlikely to be useful for quiescence.


Is there software that simulates the Tri-D or 3-D chess as seen in Star Trek? I want to try this game without making/buying a board and it is easier to learn to play when the computer can prevent invalid moves. Does any software, preferably freeware, exist which simulates this flavor of chess?

From wikipedia:

  There is software for playing Tri-D Chess; Parmen is a Windows application written by Doug Keenan and available free on his website.

Here are some of the external links for (software) Raumschach and Tri-D chess:

  http://www.pathguy.com/chess/Chess3D.htm

  http://www.cosmicchess.com/

  http://www.parmen.com/

There is a version available for Android:
https://play.google.com/store/apps/details?id=awfsoft.app.TriDChess


Master blindfold chess in 6 months I want to be able to play entire games blindfolded, atleast at the strength that I can win against beginner players. My current ELO is around 1800. I usually manage to play ok moves up to move 20, after that I struggle to see the position clearly, and have a hard time finding moves at all.

Is 6 months a reasonably timeline to expect substantial improvements? What would a good strategy be to achieve this goal?

If you spent roughly an hour a day for 6 months, then it's absolutely reasonable at your playing strength. The only chess-related thing you have to do is just practice playing blindfolded. Gradually it'll become more natural.

You could also do exercises for improving your overall memory (so not just related to chess). Such exercises are outside the scope of this community, but I'm sure you can find many online.


What happens after two kings stay on the board? A lot of times my sibling and I have played chess and have ended up with just two kings. We have never known what would happen next. Two kings on the board would somehow result in an infinite game, as each can move forever wheresoever they like Hence, in such situations, is the game cancelled, tied, or withdrawn?

This is covered in FIDE's Laws of Chess 5.2b)

  The game is drawn when a position has arisen in which neither player can checkmate the opponent’s king with any series of legal moves. The game is said to end in a ‘dead position’. This immediately ends the game, provided that the move producing the position was in accordance with Article 3 and Articles 4.2 – 4.7.

The term "insufficient mating material" describes this situation informally. However, the term "dead position" also applies to e.g. this kind of position:

[fen "8/6k1/8/p2p2p1/P2P2P1/8/1K6/8 w - - 0 1"]

Even with worst opposition, neither side can make any advances here, because the kings cannot cross the line set by the pawns. Therefore, this is an immediate draw by the same rule.


Checkmate in 6 moves Can somebody tell me the right six moves, and what has to be done? This puzzle was created vy
Fritz Giegold and published in Zeit-Magazin in 1976

[FEN "n1N3br/2p1Bpkr/1pP2R1b/pP1p1PpR/Pp4P1/1P6/1K1P4/8 w - - 0 1"]

Here is the solution:

   1.Rh1 d4 2.Ra1 d3 3.Ra3 bxa3+ 4.Ka1 a2 5.Ba3 Kxf6 6.Bb2#

It can also be found in the YACPBD chess problem database.


How can we convert PGN format to Resource Description Framework (RDF)? Is there any parser available in which we take PGN data as input and then convert it to RDF format? Has someone worked on this thing?

I do maintain that converter at UPM.
You may also want to read the (highly technical) related papers:

An Ontology Design Pattern for Chess Games
Pattern-Based Linked Data Publication: The Linked Chess Dataset Case


Where can I download gaviota endgame tables? I am looking for a link to download all 5 pieces gaviota endgame tables (which can give me DTM values).

A few links from google search (like this) lead me to the site which does not exist.

https://chess.cygnitec.com/tablebases/gaviota/

Use wget recursively: https://serverfault.com/questions/25199/using-wget-to-recursively-download-whole-ftp-directories for all the files.


Program that will give all available moves given the state of a board, including check I am trying to write a program that will give out every possible move for every piece (one move deep) given the state of a board. I have already done this such that it works with everything except check. It will allow the king to move itself into check, and it will allow a piece to be moved out of the way such that it places the king in check. I can't think of an efficient way of removing these moves from the set of moves I generate.

I am storing the board as a list of lists, where each list is a row on the board. Black is at the top and white is at the bottom. Lowercase is black, uppercase is white.

P = pawn, R = rook, N = Knight, Q = Queen, K = King.

Therefore, the starting board looks like this:

board = [["r", "n", "b", "q", "k", "b", "n", "r"],
         ["p", "p", "p", "p", "p", "p", "p", "p"],
         ["", "", "", "", "", "", "", ""],
         ["", "", "", "", "", "", "", ""],
         ["", "", "", "", "", "", "", ""],
         ["", "", "", "", "", "", "", ""],
         ["P", "P", "P", "P", "P", "P", "P", "P"],
         ["R", "N", "B", "Q", "K", "B", "N", "R"]]

So for example, board[7][2] is "B".

The moves are stored as a list of lists, where each sub list contains the current coordinates of the piece and a list of all available moves for said piece.

For example

[[[1, 0], [[2, 0], [3, 0]]], ...]

As the pawn at 1, 0 can move forward either once or twice.

These are then stored in two separate lists, white_moves and black_moves.

So, I think the best way to prevent the king from moving into check is seeing if any of the moves generated for the king are in the opponent's moves, and then removing them from the king's moves if they are.

Like

king_moves = set(king_moves) - set(enemy_moves)

However, I can't think of a good way of determining if the movement of one of our pieces will result in the king being exposed and thus in check.

EDIT: I also need to deal with situations like this

You seem to be writing a move generator.

Conventionally, a set of legal moves is generated by first generating a list of pseudo-legal moves (i.e. all moves which could be made, ignoring the fact that the king needs special treatment) and then filtering out moves which leave the king in check.

The legal move generator in Stockfish (one of the strongest chess engines) does exactly this - moveList is initialised to a list of pseudo-legal moves, which is then iterated over to filter out illegal moves with pos.legal.

You can implement the detection of legal moves by simply 'making the move' (creating a board state after the move) and then checking if any piece attacks the king, though of course more efficient implementations are possible.


What are the setups/patterns useful in defence? We have typical checkmating patterns (e.g. smothered mate). Similarly are there any standard setups/patterns useful specifically for defense?

I am not looking for standard tactics like pinning/discovery/etc. I don't even know whether to call these what I look for as patterns. Just simple setups. For example

There is this interesting relationship between bishop and the pawn. They support each other.

3r4/4B3/3P4/8/8/8/5K2/7k b - - 0 1

Similarly I could think of Knights supporting each other as well.

8/8/5n2/1k1nQ3/8/8/7K/8 w - - 0 1

I'm fond¹ of this one, after sacrificing my queen for some pieces and having to deal with all my additional material being forked all over the place :

[FEN "8/3P4/P2rP3/2p2Q2/8/3n4/8/5k2 w - - 0 1"]

Note that in this setup, the knight is not bound to its square, as it can move and get back to other pawn-defending squares in no time. It's a very flexible pattern. I marked these other squares with white pawns.

It seems to be a little harder to reproduce with a bishop, without blocking too many lines, and when not being the bishop+pawn one you already mention (which nicely fits on top on it, though).

¹ Also I love knights.


Is there any software that will print a .pgn file in scoresheet layout I'm looking for some software that will print the moves as

1. e4 e5
2. Nf3 Nc6
3. Bb5 Nf6

etc.

Instead of

1.e4 e5 2. Nf3 Nc6 3. Bb5 Nf6

etc.

Scid can export to pgn, LaTeX and HTML. During export you have the option ''Column style (one move per line)? Yes/No''

I just tried it and it works for all three export formats. That's for scid version 4.6.4 on linux.


Is there a way to use handicaps in chess to bridge the gap between players of different skill levels? Handicapping is routine in the Japanese game Go (my best game). The basic strength unit is one stone, and a one-stone difference represents a full level of difference in strength.

I (about a 1500 player) once asked a 2100 player how much of a handicap she would need to give me so that we would have an equal chance to win. "Probably a knight, maybe more," she answered. I once took a knight handicap against a 2200 player and lost, but it was a much tighter, closer game than one with no handicap.

That might suggest that a pawn is equivalent to about 200 points of rating. Apparently handicapping doesn't do much for say, a 50 point difference in strength (you just play and take your chances). But above that, there might be ways to use handicaps. Even giving someone the first move two times out of three (as was earlier done in professional Go) might do something.

Or would it? Why hasn't handicapping been done much formally in chess, as in Go?

Handicapping changes chess in a fundamental way that stones in go do not.

In go, getting an extra stone is roughly equivalent to having an extra move.  In chess, losing a piece is catastrophic, and in a game between two players that are within ~300 rating points, losing a piece means loss of the game.

One other reason that handicapping is not done this way is that while you (1500 player) might lose to a 2200 player (barely) without a knight, it is highly unlikely that a 2000 player would lose to a 2700 player at a tournament time control.

Handicapping was done before rating systems became so prevalent.  In clubs, players would be said to be "knight players" meaning that they needed odds of a knight in order to give a stronger opponent a good game.  Similarly there were "pawn" players and "rook" players.

An easier handicap between two roughly equal opponents would be to give the weaker player white.  This is roughly equal to 25-40 rating points [1].  Another common handicap is for the stronger player to play "blindfolded", meaning that he or she cannot look at the board, but has to call out the moves in order to play.


Is this endgame (sort-of Q vs K) a draw? I think the following endgame is a draw.

[FEN "7k/5BpP/3K2P1/8/8/8/8/4q3 w - - 0 1"]

My reasoning: I'm playing white. I will only move my king, always. Black's king cannot move. If the queen decide to capture any of my pieces, I will take back, so that won't work. And the queen alone cannot checkmate me, but black cannot bring a piece to help, so it looks like it is a draw.

Is there any flaw in my reasoning, and if yes, what is the flaw? Is this endgame really a draw?

According to the Lomonosov tablebases, it's mate in 40 for black. While the queen can't force mate by herself, she can force a zugzwang. In this case, when the bishop is forced to move to e8. Then, it's a matter of giving checks until the queen forks the king and bishop.

One of the longest variations given is as follows:

[FEN "7k/5BpP/3K2P1/8/8/8/8/4q3 w - - 0 1"]
[Result "0-1"]

1. Kd7 Qb1 2. Be8 Qb8 3. Bf7 Qb7+ 4. Kd6 Qc8 5. Kd5 Qc7 6. Kd4 Qc6 7. Ke5 Qd7 8. Ke4 Qd6 9. Ke3 Qe5+ 10. Kd3 Qf4 11. Kc3 Qe4 12. Kb3 Qd4 13. Ka3 Qd6+ 14. Kb3 Qc5 15. Kb2 Qe3 16. Kc2 Qa3 17. Kd2 Qf3 18. Kc2 Qe3 19. Kb2 Qd3 20. Ka2 Qc3 21. Kb1 Qd2 22. Bb3 Qb4 23. Ka2 Qa5+ 24. Kb2 Qb6 25. Kc3 Qxg6 26. Bc4 Qd6 27. Bd3 g5 28. Be4 Qc5+ 29. Kd3 g4 30. Bh1 Qa3+ 31. Kd2 Qb2+ 32. Kd3 Qb1+ 33. Ke3 Qxh1 34. Kf4 Qe1 35. Kxg4 Qe3 36. Kh4 Qg1 37. Kh3 Kxh7 38. Kh4 Kg6 39. Kh3 Kf5 40. Kh4 Qg4# 0-1


How does AlphaZero learn to evaluate a position it has never seen? Following up from answers to:

Understanding AlphaZero

My question would be how the neural net "learns" what to do in a position it hasn't encountered. Saying the actual AZ executes an MCTS using the bias + weights from the trained neural net just pushes it back a step to how the neural net calculates these values. If it was through random self-play, with no human knowledge, then how does it decide how to weight a position it has never seen?

The evaluation function of a chess engine, whether instantiated as a neural net or explicit code, is always able to assign a value to any board position. If you give it a board position, even absurd ones that would never occur in a game, it will be able to spit out a number representing how favorable it is to one player or another. Since the number of board positions in chess is unmanageably gigantic, the training can only occur on an infinitesimal sample of the game tree. The engine is not simply recalling previously calculated values of board positions, but is performing calculations based on the arrangement of the pieces. For a non-neural-net example, part of a chess engine's evaluation might be to add up the value of each piece on its side and subtract the total value of the opponent's pieces. Then, one set of parameter that would be adjusted while training would be the value of each piece.

When the engine is untrained, the values assigned to a position might as well be random since the parameters of the evaluation function start out with (usually) random values. The goal of a training phase is to adjust the parameters of the engine so that it assigns high scores to board positions that are probable winning states for the player.

From the paper on AlphaZero (page 3):

  The parameters of the deep neural network in AlphaZero are trained by self-play reinforcement learning, starting from randomly initialised parameters. Games are played by selecting moves for both players by MCTS. At the end of the game, the terminal position is scored according to the rules of the game to compute the game outcome: −1 for a loss, 0 for a draw, and +1 for a win. The neural network parameters are updated so as to minimise the error between the predicted outcome and the game outcome, and to maximise the similarity of the policy vector to the search probabilities.

[math symbols removed from quote]

In summary, during training, AlphaZero played a game against itself. When the game is over, the result of the game and the accuracy of its predictions in how the game would proceed were used to adjust the neural net so that it would be more accurate during the next game. AlphaZero is not keeping a record of every position it has seen, but is adjusting itself so that it can more accurately evaluate any board it sees in the future.