Does anyone know the anecdote about Ostap Bender? every now and then I have heard the saying "1. e2-e4 -- The favorite opening move of Ostap Bender." In Alexei Kornev's book "A practical white repertoire with 1. d4 and c4" the author writes:

  Ostap Bender is the picaresque hero of the hugely popular Russian comic novel “The Twelve Chairs” (1928) by Ilf and Petrov. It is still not widely known in the West, despite the efforts of, for instance, Mel Brooks, who made a film adaptation of it in 1970.

Unfortunately, I have not read the novel (has it anything to do with chess?) and I also have not watched the film by Mel Brooks (I only know "Spaceballs"). Ostap Bender even has a Wikipedia entry but it does not explain why his favorite opening move is supposed to be e4.

Could anyone please explain what it is all about Ostap Bender and the move e4?

As a person who read the book, I will explain:

So Bender is a con-artist from the book, and as any person of such kind he tries to transfer money from other people to himself. He has done a lot of such things in the book, but you are interested in the chess part. In this part Bender came to some average small city and was looking for a way to get some money. He found a chess club, where he decided to play chess having no idea how to do so. His idea was to create a simultaneous match with as many opponents as possible.

He called himself a GM, wrote an ads where he told that he (GM) a lesson of how to play chess and will play a simul game on 100+ chessboards. Take your chessboards, pay fee for a game, fee for an entrance and you good.

Before he started the game, he was able to persuade the owners of chess club to give him all the money by explaining them his idea how to make their city and their chess club one of the most profitable. He told that he would you all his connections in chess world (he is GM, who knows Lasker and Capablanka) to organize next world chess tournament in their city which will eventually makes it better than Moscow, New York and will give huge amount of money.

Back to simul games. When people came - he started to abstractly speak about chess, how cool the game is, how is it connected to everything without any details. Then he started his games. Because he had no knowledge how to play, he decided to play 'solid' e2-e4 (he new that he can not lose straight after that move).

So he played e2-e4 with everyone. His games were not long, soon he lost to the first guy, was doing mistakes with chess movements, tried to steal a piece and so on. He lost to almost every player and ran away.

P.S. it might not be 95% accurate and looks like a starting place for my own book, so do not be mad with inaccuracies.


How to display figures instead of letters in position analysis notation in ChessBase? I just installed Deep Fritz 14 with ChessBase. By default the notation in deep position analysis looks like this (only letters, no chess figures):

I would like to make it look like this:

How do I do this?

Nevermind, figured it out.

File > options > Clocks+Notations > Figurines radio button


How do you judge a sacrifice? I have been looking at several of Mikhail Tal's games recently, as they are exciting to analyze.  Often Tal makes sacrifices in surprising positions, and almost always the computer finds that the positions are quite close despite the massive material deficit.
How can one accurately judge the compensation from a sacrifice?  Are there any techniques to try to figure out whether or not it was worth it, and what should I be looking for here?  How can I try to evaluate "king safety" and "weaknesses," and determine whether or not they are worth the material loss?
Note: I am not just asking about a combination that returns the material.

I will assume here that you are talking about sacrificing pieces and not just pawns, which require less compensation.

For a sacrifice to work out you generally need to either 1) checkmate the opposing king, or 2) eventually gain the material back. There are other scenarios, but they're less common and I will ignore them here. Often goal 2 occurs because Black is required to give up material to avoid goal 1.

Either of those goals can be accomplished in the short term by a forced sequence that you can calculate, or in the longer term, where you don't calculate an exact sequence that will lead to your win but are confident that your good position will lead you there eventually.

Unfortunately there are not reliable quantitative compensation metrics such as "an exposed king is worth two pawns". Long-term sacrifices are generally made on intuition, which improves as one gains experience. There are some decent rules of thumb, though. Here are some good signs that your attack may succeed:

If you have two more pieces attacking his king than he has defending it.
If you are down a piece, but currently have more pieces actually participating in the game than he does (for example, both your rooks are active, but he still has one on a8 blocked in by a knight on b8).
If it is difficult for him to route his pieces back to defend his king.
If it is difficult for his king to run away (often the bottleneck is at f8).
If you have certain configurations of pieces (e.g., a knight on the sixth rank supported by a pawn, or doubled rooks on an open file) that are more valuable than you'd expect purely from their "point value".
If the king's pawn cover is broken, or if he is stuck in the middle of the board.

If, say, you can sacrifice a piece for a pawn and three of the above conditions apply, that is a good sign that the attack will succeed at one of its two general aims. But it all depends on the actual position.


Lisitsin Gambit Traps I've started to play the Lisitsin Gambit (1.Nf3 f5 2.e4), and this opening works well for me. However, I have analysed my games and found I have neglected to take advantage of several traps. What are the main traps in this opening?

You can try for Zukertort Trap in the Lisitsin Gambit line.
After 1. Nf3 f5 2. e4
the trap-line is Ng5
then if the opponent sticks with his pawn on f5, and pushes d5, then, simply play d3, followed by exd3 and then play Bxd3, and notice that the king has serious weakness on one of its diagonals.
Now, if opponent replies with Nf6, then the best option is Nxh7. If black captures with Nxh7, then Bg6(check), Kd7 and then Qxd5 (mate).
You can also go for, Bxh7 instead of Nxh7, also its winning for you, after Nxh7, you play Qh5, Kd7; Nf7, Qe8, Qxd5 (mate) and if black captures the bishop with rook, then you take it with the Knight, then Nxh7, and Qh5, checking the queen and picking up the Knight.


Games won by the stalemated player? Here is a quote from Davidson's  "A short history of chess" (Link), chapter 8, which I used in an  answer to an earlier question.

[...] In Italy, however, from the very beginning, players could not
accept stalemate as a victory for anybody. They argued that since no
legal move was possible, the game simply stopped. Consequently in
medieval Europe four different stalemate rules were simultaneously in
effect, and travelling players had to agree in advance as to whether
they were playing by the Spanish (victory for White), French
(forfeited move for Black), British (victory for Black), or Italian
(drawn game) rules. The Italian practice eventually spread throughout
the Continent, partly because of the tremendous influence which Italy
exercised on all European culture, partly because of the fame of
Italian chess players, and partly because the rule seemed inherently
logical. By the end of the eighteenth century every part of Europe
(except Britain) had agreed that stalemate was a drawn game.

So in Britain for a long time stalemate was actually a win for the stalemated player.
Question: Are there any records of historical chess games from Britain ending with a win by stalemate for the stalemated player?
Here is a bit more context from Wikipedia:

The rule in England from about 1600 to 1800 was that stalemate was a loss for the player administering it, a rule that the eminent chess historian H. J. R. Murray believes may have been adopted from Russian chess (Murray 1913:60–61,466). That rule disappeared in England before 1820, being replaced by the French and Italian rule that a stalemate was a drawn game (Murray 1913:391).

You can search up Armageddon games on chessgames.com or any other database. Black always has drawing odds in those games, so there's bound to be games where black wins by getting stalemated.


How to get better at bullet chess I am a bullet player. I play mostly on lichess and a little on chess.com. My peak rating in bullet is 1869. I have been trying to reach 1900 but I am unable to. I am also good at blitz chess, with a rating of 2518. But being good at blitz doesn't help me to get good at bullet. So, can anyone give me some tips on how I can get good at bullet?
I play 1+0, 1/2+0, 1/4+0 in bullet and 3+0 or 3+2 in blitz

I am not a good bullet player, but will try to answer anyway. Apart from the usual suggestions (studying the game and working on tactics) the following ideas come to mind:

In short time controls whose typicall completely neglected "non functional" aspects
of chess can become more important, like time management, dealing
with risk, dealing with hopeless positions, flagging and avoiding
getting flagged. Observe a few videos of Nakamura or any other chess
hero of your choice playing banter blitz/bullet, dealing with all of
that. This has helped me a lot.

In bullet flagging and getting flagged is integral part of the game.
Get conscious of it. Whose who don't like that, should simply play other formats.
E.g. if you are short of time you cannot afford
to exchange into an lengthy endgame, since your opponent will simply
start to flag you.

Since time is short, all chess features which needs comparative more
time to handle are affected negatively, at least this is what I
firmly believe (I can not a good bullet player, since I have no real
feeling for this problems). King safety gets much, much more
important. The knight gets stronger in the endgame and can become
extremly strong in the late endgame. Even the tinyiest advantages
are usuall converted, if they can be exploited long enough.

Bringing the opponent out of his comfort zone is always helpful, in
bullet it can be deadly on the spot. E.g. against the Kings Indian
attack (Nf3, g3, Bg2, 0-0) Nakamura plays sometimes in bullet d6,
Nf6, Bd7, Qc8, Bh3 and then h5 with mating attack. I copied it and it
scored deadly for me ;-).


Does the PGN specification mistakenly omit solidus (/) for symbol tokens? The Portable Game Notation (PGN) specification appears to contradict itself regarding the valid characters that may appear in a symbol token.

From [1], section 7, quote:

  A symbol token starts with a letter or digit character and is immediately followed by a sequence of zero or more symbol continuation characters. These continuation characters are letter characters ("A-Za-z"), digit characters ("0-9"), the underscore ("_"), the plus sign ("+"), the octothorpe sign ("#"), the equal sign ("="), the colon (":"), and the hyphen ("-") ...

Or, to put it more concisely, a symbol token conforms to the regular expression /^[A-Za-z0-9][A-Za-z0-9_+#=:-]*/.

However, this definition explicitly precludes the game draw termination marker 1/2-1/2.  Quoting again from [1], section 8.2.6:

  Each movetext section has exactly one game termination marker; the marker always occurs as the last element in the movetext. The game termination marker is a symbol that is one of the following four values: "1-0" (White wins), "0-1" (Black wins), "1/2-1/2" (drawn game), and "*" (game in progress, result unknown, or game abandoned).

The string "1/2-1/2" very obviously does not meet the definition of a symbol token, so either:

a) the solidus character ('/', 0x2f) should have been included in the definition of symbol continuation characters, but the author failed to do so, or;

b) game termination markers should not be considered symbol tokens, but rather a distinct type of token which is separate from symbol tokens, and the author failed to indicate this, or;

c) I have completely misunderstood the wording of the specification, and am an idiot.

Somebody has screwed up here, and either it's me, or it's Steven J. Edwards.  Hopefully it's me.  Personally I think (a) is the most likely of the three but perhaps I've missed something.

[1] http://www.saremba.de/chessgml/standards/pgn/pgn-complete.htm

You are right, the text as written there isn't exactly correct.

It also says that the marker is a symbol and lists * as one of the options, even though * is a token on its own and also cannot occur in a symbol.

That said, the meaning is clear enough, 1/2-1/2 is a valid termination marker. How you solve this in your code is up to you. As it's hard to add 1/2-1/2 as a token on its own (would need lookahead to disambiguate it from symbol 1 et cetera), it's probably easiest to add '/' to the possible symbol characters, yes.


Why is it acceptable to resign? In nearly every non-chess field of competition I can think of, it is generally considered poor sportsmanship to quit before the game or match is played to completion. When playing other board games* (Monopoly or draughts/checkers, for example) participants are expected to continue until one player has won. In athletic competitions**, it is also considered poor behavior to leave the field of play before the game is complete, regardless of the score. This is the case even if a competitor or team is trailing by a huge difference in score, there is only a little time left, and the risk of injury when continuing to play might be fairly high. Suffering through a complete game/match, even when it is lost beyond hope, seems to be an accepted part of entering into the competition.
On the other hand, chess not only allows a player to resign when they believe they are losing, but it can be considered poor sportsmanship if a player continues to play in such a situation. If you blunder and drop a queen or rook early in the game, you're insulting your opponent if you don't resign. Down a passed pawn in an endgame and your king is not "in the box"? Time to resign or face people saying you were disrespectful toward your opponent .
Thus the question: Why is it considered good sportsmanship in chess to quit before a game is fully played out?
* There are a few board game exceptions, such as Risk, where it can become obvious who is going to win. but playing the game to completion might still take hours. Even in such situations, all remaining players usually need to agree to end the game.
** In some youth sports there are rules that cause a game to be terminated early when one team has a very large lead in the score. Still, a certain minimum amount of the game must be played.

Why is it acceptable to resign?

Chess has its origins as a war game. It was used to model war and perhaps to play a part in the training of generals. In war it is standard practice to surrender when it is clear that defeat is unavoidable. This is an obvious humane thing to do to minimize loss of life. Crossing over into chess as the model of war this translates into resignation.


1. e4 e5 2. f4 exf4 3. Nf3 c5 — Sicilian Defense to King's Gambit? [FEN ""]

1.e4 e5 2.f4 exf4 3.Nf3 c5

What's the refutation of Black's unusual third move, or anyway the best way to play against it? Which is stronger, the Open Variation 4. d4 cxd4 5. Bxf4, or the Closed Variation 4. Bc4 Nc6 5. d3?

If there is no refutation (as seems to be the case), then why is 3...c5 hardly ever played, or mentioned in the books? Is it because there are so many good lines against the King's Gambit that nobody needed another one? Is it that the people who like to play c5 usually play it on the first move?

My initial reaction is that 3...c5 is very weak just by looking at it, which is why it is so rare. The ECO key that comes with ChessBase's Mega databases is very detailed, but even this does not even have its own specific sub-key.

There are 112 games in Mega 2020 database with 3...c5. The most popular response, played in 87 of the 112 games was 4.Bc4, which had a winning percentage of 64.9%, followed by 4.d4, which was played in 17 games and had a winning percentage of 61.8%). 4.d3 (6 games/33.3%) and 4.Nc3 (2 games/50.0%) were also played.

Obviously, 4.Bc4 and 4.d4 are the choices, but you also have to think about what to play stylistically: If you play the King's Gambit, you like open, tactical, positions, so it does not make sense to play the latter two moves at all unless they eventually become the natural move to finish development later. You still want to strive for the quick development of the kingside, and play down the f-file and open center.

3...c5 is weak, but as I looked through the games, the only plan that white needs to fear is the Be7 and g5 plan (possibly g5 first), holding the pawn. Black scored in the 40-50% range in most of those lines. That might bode well for the 4.d4, and early Bxf4 plan by white.

Now that I have discussed what humans play, I am going to see what Stockfish 11 says. After looking at many lines, a lot of which are below, but that is only a small fraction of what I actually looked at, I cannot say that Stockfish found any pure refutation, but I suspect that the you will do well following the main line because if black plays 3...c5, it is because black is a weak player to start with...deny black holding f4, and you will probably win most of the time as the human stats above show.

4.Bc4 and 4.d4 early on both come in with the same evals, but as the depth gets deeper (depth 33), 4.Bc4 is preferred by Stockfish, but they are both the typical minor pluses that computers typically give white in the opening, about +.5, but as I force in lines, and go deeper, everything levels out a lot. Here are some sample lines.

One last note about the play: The reason that white can play the early Bc4 in these lines, and not worry about g5, it that it seems tactically refuted if black tries to save it. White is playing a gambit line, so I was not really worried about trying to get the pawn back simply because we are down a pawn, but the computer might be; nevertheless, I was concerned because it gets in the way of developing the Bc1 and opening the f-file, so I did lean toward recovery.

Please note that there are also extensive comments within these lines.

 [FEN ""]

 1. e4 e5 2. f4 exf4 3. Nf3 c5 4. Bc4 Nc6 5. d3 {This is Stockfish's favorite, and is indicative of trying to stop the early g5 plan. It still is not the most human move, which I will also cover.} (5. d4 cxd4 6. Bxf4 Nf6 7. O-O Nxe4 8. Bd5 $1 {This leads to mind-boggling complications.} (8. Re1 d5 $17) 8... Nf6 9. Ng5 Nxd5 10. Nxf7 Qf6 (10... Kxf7 11. Qh5+ Ke6 12. Nc3 {And the other rook comes in and wins...+8.}) 11. Bg5 Qg6 12. Qe1+ Be7 13. Bxe7 Ne3 14. Rf2 Nxe7 15. Nxh8) (5. O-O $6 {This is slow, but leads to typical positions.} g5 6. d4 cxd4 7. Bxf7+ (7. g3 $5) 7... Kxf7 8. Nxg5+ Qxg5 9. Bxf4 Qg6 10. Be5+ Ke8 11. Bxh8 b6 {With wild play that the computer likes barely for black, but I do not believe that a human will survive.}) 5... Bd6 $5 (5... g5 $2 6. h4 g4 7. Ng5 $18) (5... Be7 6. Bxf4 Nf6 7. Nc3 d6 8. O-O O-O 9. Qd2 $16) 6. O-O Nf6 (6...Nge7 $4 7. Ng5 O-O 8. Qh5 $18) 7. Nc3 (7. Qe1 $5) (7. e5 $2 {This does not work due to tactics and threats of smothered mate, and the Qd1 and Bc1 hanging if the queens get traded.} Nxe5 8. Re1 O-O 9. Nxe5 Bxe5 10. Rxe5 d5 11. Bb3 c4 12. dxc4 Ng4 13. Re2 dxc4 14. Qxd8 Rxd8 15. Nc3 cxb3 16. axb3 g5 $17) 7... O-O 8. Bd2 a6 9. a4 {And the computer thinks this is roughly equal, but white is more fun to play.}


How would I know why a move is good or not? When I play chess on say lichess.org, I can see whether my move is good or not according to Stockfish. I can see why some moves are obvious blunders or mistakes, but for some other moves I don't really know why said move is bad/good. Is there a heuristic or engine or some rules I can use to see why a move is good or bad?

As far as I know, there is no engine that does what you are looking for. An engine is a program that does nothing more than take certain positional and material elements into account, and gives it an evaluation. It does not break down the elements and show you how it evaluated each of them. Sometimes, it can be obvious because the analysis is a clear win of material, but most of chess is more deeply hidden than that....sometimes VERY deeply hidden.

I found a site that does what you are asking. It takes those evaluations, and tries to put words and understanding to the numbers.

You it on one of the problems with chess-analysis software for weaker players, and that is that it just shows the strongest move per the computer, without any explanation why. There are some programs, like the ChessBase programs that, using their "Tactical Analysis" feature, attempt to give some explanation to the moves, but they are all wanting.

That said, decodechess.com seems to do better than most for newbies. As a USCF Master, the explanations are pretty good from what I can see, and the underlying "engine" is the same Stockfish that you use. Although a premium account is $99/year (right now, 50% off with the promo code "getserious". for the record, I have no affiliation with the site, nor am I a member), you can create an account, and "decode", or analyze three games per day for free. If you like it, I would jump on the promo.


How to deal with Stonewall Attack 'counter'? I've been trying out the Stonewall Attack opening and have had quite a lot of success with it. My main problem arises when my opposition doesn't castle on the king side and instead moves their king towards the queen side. It tends to be lower ranked players who do this, but I always find the games a lot tougher than when they castle their king, as I have good control of that side of the board.

My question is, what would your advice be on proceeding if this occurs? The game turns really messy, and I feel like I have less control. I am quite a new player so please bear that in mind :D.

No opening approach is equally well suited to all responses.  The Stonewall does often allow for an active king bishop, an active knight on e5, an open f-file, and the promise of a g-pawn advance against a castled King.  On the other hand, it means a diminished role for the queen bishop and (if things don't work out according to plan) the queen knight, and it gives White a backward e-pawn and some central holes.  White's center can easily become weak without a lot of piece protection there.  You'll want to be mindful of these tradeoffs when using this "telegraphed" opening.

I first learned about the Stonewall from a book by prolific author Fred Reinfeld called How to Think Ahead in Chess.  He devoted almost half of this small book to this opening, basically endorsing it wholeheartedly for the beginning player and failing to discuss its drawbacks.  He even encouraged the reader to stick as closely as possible to a specific  move order and a predetermined set of opening- and middle-game objectives.  An extraordinarily bad set of advice, on later reflection.

EDIT: You asked for advice about adapting to a Black king move to the queenside.  You might want to try to make the most of your f-file strength, going after the f-pawn and penetrating the Black position on f7.  If black creates good counterplay with a c-advance and good hits against your center, you may be able to avoid serious problems by exchanging pieces and setting up a chance to liquidate your e-pawn before it becomes an endgame liability.


In Bb5 systems against the Sicilian, why does White exchange their b5 bishop without playing a6? Isn't White giving up too much, i.e. one tempo in the opening and the bishop pair, for too little, i.e. doubled pawns?

For example, after

[FEN ""]

1. e4 c5 2. Nf3 Nc6 3. Bb5 g6

Bc6 is the second option in Lichess Masters database.

Some things that are probably part of the answer, but probably not complete and concrete enough:

1...a6 won't come. There is no threat to a pawn on e5, the knight isn't pinned, the only point of 3.Bb5 is to exchange it on c6. So black doesn't waste a tempo on forcing white to do what he was already going to do.

On the other hand, black has a choice to make, between ...bxc6 and ...dxc6. By taking earlier, white can see which way black goes and set up his pieces accordingly. If, in contrast, he takes later, black can first see where white puts his pieces and then choose which way to take. So since it's going to happen anyway, better do it immediately and not give out more information just yet.


What is it about Magnus Carlsen? It seems every where I read, Magnus Carlsen is involved in a discussion on if he is or will be the greatest chess player of all time.  It also seems as if some are crowning him world champion even though he hasn't won one yet, so my questions are what makes Carlsen so good?  Why are people so confident in Carlsen?  Does he have something other players such as Aronian don't have?  I also saw that 60 minutes did a special and called Carlsen the Mozart of Chess.  Where is all this coming from?

Carlsen is 21 years young and is currently the highest-rated player in the world. He scored a win against Karpov and a draw against Kasparov at the tender age of 13 (Reykjavik Rapid 2004), and was the second youngest player to become a grandmaster (at the time he did it). Things like that are enough to brew confidence, garner world championship expectations, and draw superficial comparisons to a similarly precocious talent like Mozart.

I imagine that his main advantage over his current closest rival Aronian in terms of grabbing attention is just the fact that he is 8 years younger. And whereas, say, Sergey Karjakin is only a year older than Carlsen, and is the one who still holds the record for becoming the youngest grandmaster ever, he simply doesn't have the sort of tournament record that Carlsen does, especially in the highest-class tournaments of the last few years. (Note that Karjakin does have impressive recent wins like Wijk aan Zee 2009, Tal Memorial 2010 and Bazna Kings 2011; but Carlsen's success of late has been such that that trophy shelf pales in comparison.)

Anyway, assuming the upcoming world championship cycle goes through as planned, then Carlsen will have his chance to justify all the chatter and expectations. But I'll be rooting for Kramnik or Aronian myself :-)


How many matches have there been at the top level which have ended up with a tied score and a winner? In the current FIDE Grand Prix tournament in Jerusalem the first round match between Pentala Harikrishna and Sergey Karjakin ended in a tied score, 4.5-4.5, but Karjakin won because the last game was an armageddon game with him as black.

In the 1950's Botvinnik "won" two world championship matches as defending champion with a score of 12-12, one in 1951 against Bronstein and again in 1954 against Smyslov. At the time there were no tie-breaks for world championship matches. Instead the defending champion retained the title.

That makes 3 matches. Are there any more?

As @Remellion pointed out, the 1987 Kasparov - Karpov world championship match also finished in a tie, 12-12, with Kasparov retaining the title.

That chessgames.com link leads on to the 1910 Lasker vs Schlechter world championship match that finished 5-5 with Lasker retaining the title. The interesting story of the match is told here. With one game to play Schlechter was leading 5-4 and only needed a draw to become world champion. Instead of playing safe he played for the win but after a game lasting 11 hours spread over 3 days he lost and Lasker retained the title.

Another tied game which had a winner was the 1983 Smyslov - Hübner Candidates Quarterfinal Match which ended 5-5 and then was extended with 4 full length tie-break games (all draws) for a final score of 7-7.

The match was held in Velden, Austria, about 500 meters from the Casino Velden and so to decide the winner they used the roulette wheel. If the ball fell into a black number Hübner would be the winner and if red then Smyslov. The first spin saw the ball end up in zero (no colour) so a second spin was needed which landed in red, so Smyslov won the match.

Robert Byrne, reporting in the New York Times, thought this was very unfair and proposed that more rapid games should be used to break ties when the tie-break games at the regular time control failed to produce a winner. Perhaps this was the first time rapid games had been suggested as a tie-break mechanism?

So, that takes the total up to 6.


Exchange in the Scotch Four Knights In the main line of the Scotch Four Knights

[FEN ""]
1.e4 e5 2.Nf3 Nc6 3.d4 exd4 4.Nxd4 Nf6 5.Nc3 Bb4 6.Nxc6 bxc6 7.Bd3

What's wrong with 7...Bxc3 ?

It seems this move is played very rarely, but, when I play White, I would not like to face it, because of the horrible pawn structure White gets, with isolated doubled pawns and another isolated pawn. For example, see the position after the normal moves 7...Bxc3 8.bxc3 d5 9.exd5 cxd5.

Of course I see that White gets the Bishops pair and an open b-file, and he can also play Ba3 preventing Black from castling. But is this enough to compensate for the bad pawns? Or is there something else that I don't see? What should be the plan for White after 7...Bxc3 ?

I think you got it basically right. White gets the bishop pair which in an open position like this, is a real advantage. Also black currently does not have any good squares for his pieces. Lastly, it is difficult for black to take advantage or to attack the doubled isolated pawn.

White's dark squared bishop could go to g5 where the pin of the knight is kind of annoying or to a3 where it might hinder black from castling.

Regarding your proposed continuation, I believe that after 7...Bxc3 8.bxc3 d5, white can play 9. e5 asking the knight where it wants to go. Also after black's d5 the a3-f8 diagonal gets weak and the bishop on a3 will be really strong.


Leela chess zero weight files I'm using Leela chess zero for a couple of days and found a couple of weight files here. But what is the place to be for weight files? I can imagine that lc0's strength is determined by the weight file.

For example, as you can see here, the project has a couple of weight files, which one should I use?

The weights for main networks are here. The best weights depends on whether you are using a cpu or gpu. For cpu, the best weights file is probably LD2 which is a small net trained off of data for t40. For strong gpus or longer searches, one of the recent t40 networks will be very strong.


Can anyone tell me name of this opening where knight is sacrificed? Is there any way to take knight and save rook at same time?

Please do tell name, so I can search on YouTube.

 [FEN ""]

 1. e4 e5 2. Nf3 f6 3. Nxe5 fxe5 4. Qh5+

As Akavall said correctly, it is the Damiano Defense, and is named after Pedro Damiano (1480–1544).

Since he answered the basic question about the name, I would not normally, but there is an additional part to the question, so I am going to add that 2...f6? is virtually a forced loss, no matter how you play it, and here is the analysis. So, no you cannot take the knight, and save the rook, or worse happens.

 [FEN ""]

 1. e4 e5 2. Nf3 f6 3. Nxe5 fxe5 $2 (3... Qe7 4. Nf3 Qxe4+ 5. Be2 d5 6. O-O {And black is already dead on the e-file. The immediate threat is Bb5+ and Re1 winning the queen. The ugly Ne7 is the best move here.} Ne7) 4. Qh5+ Ke7 (4... g6 5. Qxe5+ Qe7 6. Qxh8 Qxe4+ 7. Kd1 $18) 5. Qxe5+ Kf7 6. Bc4+ d5 (6... Kg6 7. Qf5+ Kh6 8. h4 $1 Qe7 9. d3+ g5 10. hxg5+ Kg7 11. Bd2 d5 12. Bc3+ Nf6 13. gxf6+ {And mates in four.}) 7. Bxd5+ Kg6 8. h4 h6 (8... h5 9. Bxb7 Bd6 10. Qa5 Nc6 11. Bxc6 Rb8) 9. Bxb7 Bd6 (9... Bxb7 10. Qf5#) 10. Qb5 Nf6 11. Bxa8 $18


Pawns in the center: strength or weakness? In most openings, pawns typically end up at some of the centre squares. There is really no other way to open up the long diagonals(c1-h6,a6-f1) for the bishops. However, how desirable is this? Hypothetically speaking, assuming there were some special rules in chess which allowed bishops to be developed along these long diagonals without having to push away the e and d pawns, would these pawns still end up getting pushed onto the centre squares?

Yes. The main reason to move your d- and e-pawns forward is to control the center with them. The fact that they allow the bishops to be developed is secondary. (Often bishops are fianchettoed anyway.)


Lichess summary analyzer tool I'm trying to find an online tool that I had once used to analyze my games. It allowed me to import thousands of my games from Lichess and showed what my most common opening mistakes were. The only thing it needed was my Lichess user name.
I had learned about that tool from an Eric Rosen twitch stream. I used it only once on that day. It's been a while since then and I've forgotten the name of the website. I tried searching for various keywords but I'm unable to find it. Maybe it's not visible to search engines?
I would like to know what website it is.

I suspect you are looking for OpeningTree


What's "National Master" in China? Someone told me he's a national master in the Chinese rating system (not FIDE). His English wasn't very good, so he wasn't able to communicate more. He doesn't have a FIDE rating. He has only played rated games in China.

What does that mean? What's his approximate FIDE rating? My guess is around FIDE 1900, because I was able to defeat him. Correct?

TL;DR: gaining national master level in China is based on gaining competition norms, likely to be in the amateur league.

As you know, national federations can set their own standards for national master titles:

  National chess federations are free to set whatever standards they want for such titles [e.g. National Master], which are not recognized by FIDE. Standards for "Master" titles in different countries vary, but are usually based on criteria such as achieving a certain rating (typically about 2200 Elo), achieving the required number of tournament performances ("norms") at a certain level, or featuring prominently in the country's national championship. In some cases, it may extend to honorary titles awarded to (for example) prominent chess administrators, business patrons or politicians.

Source: wikipedia, emphasis is mine.

In China, you can gain the national master title by playing in tournaments and getting NM norms;

  There are really two tracks for chess players. One is run by the National Chess Association & the National Chess Academy, as well as the associated provincial- and municipal- level chess academies. They award certificates for amateur players, from level 6 (the lowest) to level 1 (the highest), which are followed by the titles of Candidate Association Master Association Master & National Master. Meanwhile, the National Sports Bureau uses a different classification system entirely (recognising instead the ‘Athlete system’), bestowing upon the elite players the titles of Third class (the lowest), Second class and First Class (the highest) Athlete, National Elite and International Elite.

  Chess players gaining the required norms (gaining a certain placing in some designated tournament perhaps, or satisfying the required win rate) can apply for First Class certification. For example, I gained the titles of Association Master and First Class Athlete through competing in various events.

Source: Chess in China: Unveiling the Chinese System on Chess.com, emphasis is mine


Creating opportunities for tactics other than by enemy mistakes Tactics, such as the pin, skewer, and fork, take advantage of uncompromised positions of pieces, and sometimes inadequately guarded pieces. Usually, tactics can also occur during an intermezzo.

If both sides made positional improvements with every move, followed their plan, and made no mistakes, could tactics take place because of the evocation of an incorrect plan?

Perhaps in that case, at least one of the moves was an incorrect move because it's supporting the manifestation of an incorrect plan (wrong strategy).

How can one make sure, other than by scanning for the positive conversion of the seven imbalances and looking out for checks, captures, and threats, that an opportunity for a tactic is created?
What are some tips to ensure one is following a correct plan (such as counting that your plan will become effective before his)?

Theoretically if both sides play perfectly the game should be drawn.  Someone has to make a mistake for the other side to win.  According to that logic, material-winning tactics would not be possible without an error, an unlikely scenario I know.  Or to invert that, if such tactics were possible, by definition a mistake must have occurred.  If you are gaining space, protecting everything and looking for imbalances that you can exploit, I'm not sure there's much else you can do, particularly against someone else who is doing the same.


How to read score from stockfish - inconsistent response every call? I was setup stockfish with:

uci
setoption name hash value 128
setoption name threads value 4

That I try to evaluate my first moves to learn how it works (I am programmer) but I received random results.

go depth 20

First result cp = 16

info depth 20 seldepth 30 multipv 1 score cp 16 nodes 1327846 nps 1074309 hashfull 585 tbhits 0 time 1236 pv e2e4 e7e6 d2d4 d7d5 e4d5 e6d5 f1d3 g8f6 g1f3 f8d6 e1g1 e8g8 b1c3 c7c6 f3e5 f8e8 c1f4 f6g4 f1e1 d6e5 f4e5 g4e5 e1e5
bestmove e2e4 ponder e7e6

Second result cp = 20.

info depth 20 seldepth 29 multipv 1 score cp 20 nodes 4912037 nps 1040685 hashfull 986 tbhits 0 time 4720 pv e2e4 e7e6 d2d4 d7d5 e4d5 e6d5 f1d3 g8f6 g1f3 f8d6 e1g1 e8g8 b1c3 b8c6 c1g5 c6b4 c3b5 h7h6 b5d6 d8d6
bestmove e2e4 ponder e7e6

Why each time Stockfish produce something else for 20 depth - different scores - same move e2e4?

The reason is simple - hashing. The first time you run the analysis, the engine stored the computed positions in a hash-table. This table was not clear the next time you run the analysis. Next time, when you ran the same analysis, the engine could search further and thus returned a different score for it's principal variation.

Evidence? Note the node counts was: 1327846 for your first attempt and 4912037 for your second attempt. The NPS (nodes per second) was very close (1074309 vs 1040685). Clearly Stockfish used the existing hash-table to skip moves it had already computed in your first attempt.

Note that this is an expected behaviors, clearing hash-table after each move would dramatically reduce the engine strength.


Best black opening move for E4 Can some one tell me which is the best opening move when white plays e4, read somewhere, to counter e4 Sicilian Defence is one of the best?

Your question is unanswerable, please consider rephrasing it.

The reason for me saying this is that every opening that has = evaluation in ECO is good response to 1.e4. You could look for statistics on openings but it is useless-in my opinion statistics are stupid since they reveal to you nothing about the game. It is just a result of mathematical division-you can only use them to see which defense to 1.e4 is the easiest to play with for most of the people.

Compare the French defense and Sicilian defense:

Currently Sicilian defense "scores better" than French defense according to statistics, but that conclusion is "valid" if you sum up the efficiency of all the variations in both openings.

If you remove the dubious Rubinstein variation of the French defense from the calculation than it scores nearly as good as the entire Sicilian defense.

My point is that you have many good opening moves against 1.e4, you just have to pick one you like.

Browse through openings against 1.e4and pick one that suites your style.

This depends entirely up to you-if you like slow games with small amount of variations to learn then pick some semi-open defense ( Caro-Kan, French-defense and so on ) or if you have time to learn and wish open battle riddled with sharp tactical play then pick Sicilian defense or Modern defense or whatever.

Remember: Each opening that is evaluated as valid, meaning it gives equal chances to both of you for winning is a good candidate.

You need to choose one that suits your style and just go with it.

If you have further question leave a comment.

Best regards.


A tactic on the Chekhover variation of the Sicilian? Recently I found the game Tal vs. Byrne (1976), that opens with Chekhover Variation of the Sicilian Defense. What got my attention in this variation was move 7, for, just like Tal did, every engine says that the best move is 7. Nc3, but for some reason I like how 7. Ng5 looks:

[FEN ""]
1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Qxd4 Nc6 5. Bb5 Bd7 6. Bxc6 Bxc6 7. Ng5!? (7. Ng5 e5 8. Qc4 Qd7)

Stockfish 6 says it is slightly better for black (-0.8 at depth=22 to be precise), but the main idea is simply to explore the weakness of the f7 pawn. The main line I was thinking was 7... e5 8. Qc4, the natural urge to punish the white queen at the center creates the threat of mate on f7, so black is somewhat obligated to lift the queen to the 7th rank. Anyway, if this "trick" fails, for example after 8... Qd7, there is no immediate advantage for white, and it seems that the only difference from Tal's 1976 variation is that here white is behind in development (and ready to be punished!).

I couldn't find any game with the move 7. Ng5 in chessgames.com, but I still think that it is a natural looking move that seems to have a possible tactic behind it, even if I wasn't able to find. So my question is:

  Is 7. Ng5 really only a bad move? The downside is that obvious? Or there is a possible tactic behind it? (besides the threat of mate on f7 after 7... e5 8. Qc4)

Strategically the knight is misplaced on g5.  When black plays e5 in the Sicilian, the ideas revolve around white trying to control the d5 square, and black trying to play d6-d5.  Simply put, if black can play d5 damaging his position (i.e. sometimes if the king is still in the center d5 opens up the black king) black will have a clear advantage due to the central pawn majority.

In order to control the d5 square, white usually plays Nc3 and Bg5.  Bg5 is important because it will either pin black's knight to the queen or allow white to trade off black's knight that controls d5.  With the white knight on g5, black will eventually gain a tempo by playing h6 which will also prevent access to g5 by the dark square bishop.

Additionally, with the queen out of the way on d7, black can quickly play Ra8-d8 in order to take better control of the d file and help support the eventual d5 push.  All of this would be pretty comfortable for black anyways, but in the Chekhover, black also has the bishop pair which will benefit from the opening of the center when black plays d5.

Long story short, white is ceding a fairly large positional edge to black in exchange for some very short term tricks.  That's not to say that white is losing, but after Ng5, black can easily claim equality straight out of the opening, and black has very good prospects to consolidate an advantage.


Capturing (almost) free piece by King Here's a position in a chess puzzle:

[Title "White to move"]
[fen "5rk1/p7/Q1n3pp/3q1p1n/2B2P2/4P2P/P5rK/R4R2 w - - 0 1"]

The rook had captured a pawn, resulting in a check. The rook is supported by the Queen, but the Queen itself is pinned by the bishop and hence will not be able to protect the rook if the King takes it.

Shouldn't King-captures-Rook be a valid move in this case?

No, absolutely not. You are putting your king in check first from the Qd5.

If you think about this way: Who could take the other king first since that really is what checkmate is? In this case, Kxg2 Qxg2 captured the white king first, and only after would Bxg8 take the black king...White lost the king first.

Your thought also does not hold up to logic: White makes an illegal move, so black cannot?


We found out that we made an illegal move later on in the game I am playing with my friend. I didn't notice that my king was in check, so I made an illegal move. We noticed this after several more moves.

What should happen next? Do we restart the game or continue it as is?

FIDE Laws of Chess 7.4a

  If during a game it is found that an illegal move, ..., has
  been completed, the position immediately before the irregularity shall be
  reinstated. If the position immediately before the irregularity cannot be determined
  the game shall continue from the last identifiable position prior to the irregularity.
  The clocks shall be adjusted according to Article 6.13. The Articles 4.3 and 4.6 [touch move] apply
  to the move replacing the illegal move. The game shall then continue from this reinstated position.

Of course, if you are playing with your friend, you can choose to do whatever you feel would be best. The above is simply what would happen in a FIDE tournament.


How should I play against the Alekhine? I like to play the variation below, although it may seem a little bit awkward.

[FEN ""]
1. e4 Nf6 2. e5 Nd5 3. c4 Nb6 4. c5 Nd5

From here you can play Nc3 or Bc4. White will have a lot of space and if the black player is going to play it wrong, he will have a disadvantage for the complete game.

1.e4 Nf6 2.e5 Nd5 3.c4 Nb6 4.c5 Nd5 is known as the Chase Variation and is playable, though not considered to be particularly great for White.

At the highest levels, the most popular variation for White is the Modern Variation, 1.e4 Nf6 2.e5 Nd5 3.d4 d6 4.Nf3. However, Black is left with a lot of freedom about how to continue, so White needs to be ready to handle a lot of continuations.

At club level the most common continuation seems to be the Exchange Variation, 1.e4 Nf6 2.e5 Nd5 3.d4 d6 4.c4 Nb6 5.exd6 (note that moves 3 and 4 are often reversed). Play proceeds differently depending on how Black recaptures the pawn.

The most aggressive (and most principled) choice for White is the Four Pawns Attack, 1.e4 Nf6 2.e5 Nd5 3.d4 d6 4.c4 Nb6 5.f4. White stakes out a ton of space but has to prove that he hasn't become overextended. Play often becomes very tactical.


What are the differences between the How To Reassess Your Chess books from Jeremy Silman? How To Reassess Your Chess 1st, 2nd, 3rd, and 4th Edition

What's the difference? Are these improvisations or just parts?

The editions do not form a series. It just is that the 4th edition is the one released at the latest date (October 2010) with revisions to the text.

There is also a workbook which contains a summary of the main book, with about 300 examples with detailed answers. This was released in December 2000. This is the book that I personally found the most useful.


About Alan Turing and chess I read Turing had some algorithm or method he could use to play chess 'against' this pen and paper algorithm assigning certain numerical values to each piece. Is this true? Is there a pen and paper algorithm one can use to play a kind of chess with oneself?

Yes, he played a game against Alick Glennie, actually he created an algorithm based on mathematical calculations. Then he tried his algorithm using pen and paper to do calculations.

[fen ""]
[White "Alan Turing"]
[Black "Alick Glennie"]

1.e4 e5 2.Nc3 Nf6 3.d4 Bb4 4.Nf3 d6 5.Bd2 Nc6 6.d5 Nd4 7.h4 Bg4 8.a4
Nxf3+ 9.gxf3 Bh5 10.Bb5+ c6 11.dxc6 O-O 12.cxb7 Rb8 13.Ba6 Qa5
14.Qe2 Nd7 15.Rg1 Nc5 16.Rg5 Bg6 17.Bb5 Nxb7 18.O-O-O Nc5
19.Bc6 Rfc8 20.Bd5 Bxc3 21.Bxc3 Qxa4 22.Kd2 Ne6 23.Rg4 Nd4
24.Qd3 Nb5 25.Bb3 Qa6 26.Bc4 Bh5 27.Rg3 Qa4 28.Bxb5 Qxb5
29.Qxd6 Rd8 0-1

The main idea of algorithm is here:

Mobility: For the queen, rooks, bishops, add the square roots of the number of moves that the piece can make, counting a capture as two moves.
Piece safety: For the rooks, bishops and knights add 1 point if there is one defender and 1.5 if there is more than one
King mobility: For the king use the same method of scoring as for the piece, but do not count castling
King safety: Deduct points for the king's vulnerability, defined as the number of moves that a queen could make were it on the square of the king
Castling: add 1 point if castling is still legally possible after this move. Add another point if castling is immediately possible or if a castling move has just been made
Pawn credit: score .2 points for each rank advanced and .3 points for each pawn defended by one or more non pawns
Check and mate threats. Score 1 point for the threat of mate, and .5 points for a checkmaterial values used to each of the pieces were:pawn =1, knight=3, bishop=3.5 rook =5, queen=10


Ways to evaluate a position? I was wondering if the only way to evaluate a position is by looking for next moves like a chess engine does.

Is it possible with only a static evaluation of the board to get a correct evaluation about which side has the best position?

Evaluate without calculating.

Source: The wisest things ever said about chess by GM Soltis

So yes, we should evaluate a position before selecting candidate moves and calculating concrete variations. Considering whether the opponent's king is safe will help you decide whether you should look for a mate in N type move, which is very different to capitalising on a space advantage.

From Tune your chess tactics antenna: know when (and where!) to look for winning combinations by Emmanuel Neiman, he recommends the following steps to selecting a move.

Global vision: think of this as walking past a game and your first impression being 'white is winning' or 'it's about equal'
Analysis of the position: This is where you look at king safety, material, space etc.
Looking for the theme: is there the potential for a pin, fork, back rank mate etc. in the position?
Looking for candidate moves: based on steps 1-3, generate a small list of candidate moves (usually 2 or 3)
Calculation of variations: work out the candidate moves as far as you can, and evaluate that final position

I would argue that steps 1-3 fall into the category of evaluating a position without looking ahead.


What sets chess players apart? I want to improve at chess, like everyone does. I am trying to structure my study to get the most out of if. But this plan needed a fundamental question to be answered, what sets masters apart from hobbyists?
I have grinded tactics and read positional books, all in vain. Therefore I decided to analyze how grandmasters think.
Now I was not very successful in my analysis, but it made me wonder, is the only reason that Grandmasters are better is that they can calculate deeper? Due to how neural networks play closer to a human style than traditional engines, I was not satisfied with this answer. Is it that they can spot when a position asks for dynamic play, or when they should solidify their position? I had no answer to this.
So what does a player at a higher Elo do better than another? I am not talking about a level where simple/hard tactical mistakes or openings lose a game. How do the top level players slowly push those beneath them into a worse position?
Note my question is not about self improvement but rather contradistinction of levels of chess play.

So what does a player at a higher Elo do better than another?

The answer I got from "It's Only Me", Geoff Lawton and Mike Fox's biography of England's first OTB GM, Tony Miles, was that the stronger player loves the game more than you do to the extent that it is almost the only thing that matters in that person's life.
Here are a couple of excerpts from "It's Only Me":

From the age of 11 he played competitive chess several times a week.
This was the beginning of a pattern of intense chess activity that was
to last his whole career.

and this from one of his school reports:

Perhaps one day he will realise that there are more things in heaven
and earth than chess. At the moment he cannot conceive of such a
possibility. Thus his only creditable activity in this subject has
been that he has turned up. Otherwise he has said nothing, done
nothing and looked pretty bored.

At least Miles completed high school and even the first year of a maths degree at Sheffield University as some form of quality-of-life insurance before getting the GM title and dropping out. Bobby Fischer dropped out of high school at the earliest opportunity at 16.
By the way the question -

is the only reason that Grandmasters are better is that they can
calculate deeper?

already has several answers here.


dark-squared Bishop in KID In the typical KID black tries to play for a mating attack. Consequently, the dark squared bishop usually ended up sleeping on g7 or sometimes reroute itself to defended the d6 pawn which is critical in KID. (correct me if my understanding is wrong)

So my question is the following.
1. Should we trade our dark squared bishop for any of white's pieces, because it doesn't participate much in terms of checkmating White's king.

My understanding is that the dark squared bishop on g7 in this opening is a strong defensive piece and should be preserved there if possible.  White I know will typically try to trade off this bishop to enhance his own kingside attacking chances, by playing his dark squared bishop to e3 and supporting it with his queen on d2 so he can penetrate with this bishop to h6 to trade off black's g7 bishop.  Doing so will then weaken the dark squares around the black king, giving white better attacking chances there.


Mistake in FIDE elo calculation? One of the properties of an elo rating system is that the sum of all elo changes is zero. When calculating the new FIDE elo ratings, the elo changes are added to the old ratings and the new ratings are rounded. However, doesn't the last step create rating points?

Say, player A has 110 ratings points more than player B and both players have a K-factor of 10. When player A wins against player B, he gains 3.5 points, while player B loses 3.5 points (see FIDE elo calculator). But after adding the elo changes and rounding the new ratings, player A will gain 4 points and player B will lose only 3. As a result, the zero-sum property is violated.

An example of such a case can be found here: the elo calculations of player 1 and player 2.

Am I overlooking something? If not, has this been noticed and pointed out before?

Wouldn't it be more correct if the elo changes are rounded first, before adding them to the old rating? (In the example, -3.5 would be rounded to -4.)

Or is this effect so small that it can be neglected, compared to other effects like the inflow of new players, different K-factors, etc...?

The effect is small. On average, once out of every 20 rating periods a person plays rated games, a person's rating will be rounded up instead of down. A rating period is one month. Assuming everyone plays every rating period (which of course is not the case), this will create 30 points every 50 years.

There are known deflationary effects from new players - they often enter near the bottom, then gain points, and usually never lose all the points they gain. It's possible the rounding is intentional as one way to insert an inflationary pressure to combat that.

I don't think they will institute decimal points on ratings, regardless. The USCF uses a rating system with a decimal point and a complicated formula. The FIDE rating system, in contrast, was designed so anyone could calculate their own rating change based on their results and the published ratings of their opponents.  Adding decimals would make the math slightly more complicated and would make it necessary to publish those decimals for people to calculate their ratings.  We've already seen a GM throw a game in protest at perceived unfair pairings; even though pairings are deterministic and were not manipulated in that case, the pairing rules are complicated enough that the GM couldn't easily determine this at the time. Perhaps FIDE doesn't want them questioning their ratings as well.


Can the king capture his attacker? Can the king get out of check by capturing his attacker? For example, if the queen comes right in front of the king, can the king capture the queen, or must another piece capture the queen?

There are three ways to get out of check.

Simply move the king away.
Block the check, or place a piece in between the king and the opponent's attacking piece.
Capture the piece that's checking the king.

All of these cases are dependent on the fact that immediately after you make your move, the king is not in check. Therefore, you may capture the queen so long as the king is no longer in check after you make your move.


ChessBase: how to efficiently use two reference database simultaneously In ChessBase I use the Mega Database as my reference database when in a board. However, I recently downloaded a Correspondence database and would like to look up positions in it as well. Is there a way I can easily use both reference databases when in a board?

So far what I'm doing is keeping the Mega Database as my default Reference, and for the Correspondence Database I: right click on it --> click opening reference --> and another board pops up where I can look up things in it. However, this is a bit inconvenient since I must keep tabbing between the two boards and manually making the same moves on each of them.

Is there a way I can easily use both reference databases when in a
  board?

The obvious way is to create a new database by merging MegaBase and your correspondence database and use this new database as your reference database.


Book recommendation on zugzwang I am looking for a book recommendation on endgames. More specifically, I want to know how to avoid zugzwang, and what to do in case it arises.

If you know of any book which has in-depth case study on endgames which end up in zugzwang, please give a suggestion.

If you are in Zugzwang, by definition, there is nothing you can do, because any possible move leads to a disadvantage.

Most typically Zugzwang appears in endgames with few pieces, particularly in pawn only endgames where is is used as a very common technique. I believe that if you study pawn endgames you should encounter it very often and get very familiar with it, so that you can keep it at the back of your mind when doing calculations.

I would not focus my endgame on avoiding Zugzwang as there are usually other things to take into account as well.


What constitutes a chess ecosystem? I'm been thinking about the metrics to measure to make a "Best Cities for Chess" list. Assume I'm going to call these cities as "Chess Ecosystems", what are some of the things that would indicate its health?

ex: Number of FIDE rated players, tournaments organized every year, coaches available, etc.

What will you add to this list ?

The parameters I can think of:

Number of

Chess club members
FIDE rated players
FIDE titled players
Grandmasters
Female players
Tournaments
Seminars / lectures

I'm not sure how to convert these parameters into a final score, nevertheless I'm curious how the list of best chess cities would look like. I would expect Moscow to be clear number one (many resident grandmasters, many tournaments). I'm also wondering how good Saint-Louis would score.


Is computer chess exhibiting the predicted "draw death"? At various times, even going back 100 years or more, people have been predicting the "draw death" of chess meaning that top players will get so good that every game will be a draw.

In the 1984 World Championship, this prediction seemed to be coming true when the players drew an exhausting 40 times. There was even one stretch in that match when 16 games were drawn in a row.

Now, that computers have exceeded human ability in chess, are they drawing more or less than top human players? Are they exhibiting draw death?

For what it's worth, here are the rates of decisive games of the TCEC seasons 4 'til 8 superfinals. Season 4 is a bit of an outlier (maybe a rule change?), but after that the percentage of decisive games drops consistently.

Season 4: 10/48 = 20%

Season 5: 18/48 = 37%

Season 6: 19/64 = 30%

Season 7: 11/64 = 17%

Season 8: 11/100 = 11%

Arguably at an even higher level are the games in correspondence chess which are played with engine assistance. I'm too lazy to count all the decisive games in the recent decades of the correspondence world championships, but in 2003 the rate of decisive games was 32% while in 2013 (two games still running) the rate has declined to 12%.

2003: 34/105 = 32%

2013: 17/134 = 12%

These numbers indicate that there is a draw death in chess, somewhere north of 3200+ Elo.


What if Stockfish had infinite computing power? If Stockfish had infinite computing power, or perhaps connected to all Google servers, etc. would it be able to solve the perfect chess moves after 10 moves? Or be able to create the perfect game directly? What would happen?

No.

What do you mean by "perfect" chess moves after 10 moves? We don't know they are perfect until the game ends in checkmate! You'll need go mucher deeper than 10 moves. You can't even solve King's Gambit in just 10 moves.
The Stockfish algorithm heavily skips stupid moves off the search tree. It will not search everything no matter what CPU power you give it. You're actually talking about a brute-force engine (search all the possible moves). No, Stockfish is much smarter than that.
Nothing really happen. You could publish a new paper, but your results would not change the world. We don't need to know what happens after 10 moves, we want to know what happens after 100 moves.


Is the Scandinavian Defence inferior? As Black, I have never played the Scandinavian Defence, nor have I ever liked the Center Game for White.  It seems like 1. e4 d5 wastes valuable time after 2. exd5 Qxd5 3. Nc3 and Black's Queen must flee, while White can comfortably develop:

The same drawback goes to White in the Center Game:

[FEN ""]
1. e4 e5. 2. d4 exd4 3. Qxd4 Nc6

But the opening, notwithstanding, appears to be still popular, and online players have often played it against me.  Is there some redeeming virtue that I'm missing in this defence?

Here are a few reasons one may take up the defense:

Despite having the Queen kicked by the Knight, the Queen is in no real danger of being trapped, its most common escape locations being to a5 and d6.
Black's pawn structure is solid, in similar ways to the Caro-Kann.
The number of lines Black needs to know are fairly limited, this makes it an easy defense to get into.
It's not played very often, so the Black player will likely have more familiarity with the positions than White.
Black is able to develop all the pieces and castle in relative safety; notable is the ability to develop with the Bishop on c8 before ...e6 is played.


Uniquely Satisfying Puzzle Here is a fun puzzle I found some time ago. It was created by Karl Fabel in 1952 and published in Rätselstunde.

Goal

[title "White to move and NOT checkmate in one!"]
[fen "B5KR/1r5B/6R1/2b1p1p1/2P1k1P1/1p2P2p/1P2P2P/3N1N2 w - - 0 1"]

This is honestly one of the most unique puzzles I ever saw.

It will take some time to find the solution but it is very satisfying once you do.

  Hopefully there is a way to post a comment with your guesses without spoiling the fun for others. Please use >! to hide your post and prevent spoilers.


Is there any UCI engine that presents DTZ information from syzygy in analyse mode? Many UCI engines that can read syzygy database put same score for every winning move (#1000 in komodo, +123.53 in stockfish, ...) and you have no idea how to make real progress when analysing root positions with them. Is there some UCI engine that scores move based on dtz value?

I understand that this dtz value is something new and that it doesn't fit very well to standard way moves are scored by engines, but without this dtz value engine becomes useless when material is reduced to 6 pieces.

Stockfish has an undocumented, non-standard command "d" which prints, among other things, the DTZ value. Some interfaces, for example, Arena, let the user give commands to the engine manually.


Can a player resign after checkmating their opponent? A friend of mine recently told me that once, he checkmated his opponent and then immediately resigned because he thought his win was unfair. This happened in a FIDE-rated tournament.
Searching the FIDE Laws of Chess, I found (emphasis mine):

1.2 The objective of each player is to place the opponent's king 'under attack' in such a way that the opponent has no legal move. The player who achieves this goal is said to have 'checkmated' the opponent's king and to have won the game. [...] The opponent whose king has been checkmated has lost the game.

5.1 The game is won by the player who has checkmated his opponent's king. This immediately ends the game, provided that the move producing the checkmate position was legal.

Is this possible in any way, for example, move the piece, don't press the clock, and then resign?

No, this is not possible.

for example move the piece, don't press the clock and then resign?

In particular, that loophole is explicitly covered by the rules:

6.2.1 During the game each player, having made his move on the chessboard, shall stop his own clock and start his opponent’s clock (that is to say, he shall press his clock). This “completes” the move. A move is also completed if:
6.2.1.1 the move ends the game (see Articles 5.1.1, 5.2.1, 5.2.2, 9.6.1 and 9.6.2)

and 5.1.1 is 5.1 in the version of the rules you quoted, so checkmate ends the game before the clock is pressed.
I guess both players could pretend the checkmating move wasn't made (or pretend they don't see it's checkmate), but this is considered cheating, and when discovered may result in both players losing the game and even being expelled from the tournament.


An interesting positional chess riddle I was thinking about a situation on a chessboard. You can call it a riddle, but I am not sure whether it is solvable or not.
Let's say that there are more than 5 pieces for both Black and White, including the kings, on a chessboard and it is White's turn.
The Riddle: Is it possible to arrange all the pieces on the chessboard, in such a manner, so that, for every possible move by White, the Black king gets checkmated? Can you construct such a position?

What I've thought so far:
Since King can't give a checkmate (apart from exceptional cases of a two queens/two rook mate), the White king should be immovable. Otherwise, the criteria of the riddle can't be fulfilled. But thinking about it this way, I can't set up any position that meets the criteria of my riddle.=

[FEN "K3k2n/7n/rr1R3N/7n/8/8/4BQ2/4R3 w - - 0 1"]

1. Bxa6#

Here is a much more simple situation where White only has only one legal move, which is a discovered checkmate.


How to beat King's Fianchetto Opening Modified (White) [fen "r1bqkbnr/ppp2ppp/2n1p3/3p4/3P4/6P1/PPP1PPBP/RNBQK1NR w - - 0 1"]

I have a few friends who I play with. Recently they have picked up on one of our better player's openings and it's surprisingly effective for development of the white pieces and positioning.

I can't figure out how to beat the opening effectively. I need to be able to shut it down where it starts. This should be noted, the pawn that was moved to d4 is there to help develop the Queen. After this the next step for white is to develop the dark-squared bishop to b2, and after that to move the knight from g1 to h3. After which comes a king side castle.

I'm unsure how to interrupt this opening other then to make an island on d5 and e6 to protect my rook. Is there any way to fully shut down this opening?

I know this opening relies on the bishops but I do not know how to get rid of them without suffering losses worse than gains.

You can develop your pieces pretty much any way you want and no big trouble can be caused to you by White.

However, I would postpone the ...e6 move, as your light-squares bishop gets blocked for no benefit (you could also try ...e5 with enough preparation). You may also want to break the center with a ...c5 push, so, although there is nothing particularly wrong with your play, my favourite move order would be

 [fen ""]

 1.d4 d5 2. g3 Nf6 3.Bg2 c5!?

now forcing White to make a choice


Are there any websites that allow standard correspondence chess time controls? I noticed that most websites that allow correspondence chess have time controls that are per move. I believe that historically correspondence chess was played with x days per y moves, which allows one to distribute time where it is needed most, while not making games excessively lengthy, and taking into account the length of a game. As far as I know, official international correspondence chess tournaments are still played this way.

Are there any free online websites that allow this, even if only to set up opponents who can play via e-mail (maintaining a ratings system)? If there are no free sites, what are the non-free options?

An answer to this question Best websites for correspondence chess? listed 5 sites, but I checked all of those and none of them seem to allow standard time controls.

http://ChessTempo.com offers a wide choice of correspondence time controls including a fixed number of days per game, or increment after a move. Just check it out.


Franco-Sicilian Defense Theory I am wondering what the main lines and point of the Franco-Sicilian Defense are for Black. I could barely find any theory about it online, and it' is my favorite opening as Black. As such, I am looking to improve on it. Any reference material will also do!
I also wonder why it is so rarely played. The engine doesn't hate it that much, and it fights the center very well, as well as allowing for a quick queen and dark-squared bishop battery in the midgame. So what is the effective response from White that makes it so unplayable? I have yet to encounter one.
[FEN ""]

1. e4 e6 2. d4 c5

It is certainly playable. The main drawback is that you give White the choice between two very different mainline openings:

3.Nf3 transposes to a Sicilian, where Black is already committed to e6 (Kan, Taimanov or Scheveningen, but no Najdorf, Sveshnikov, etc.).
3.d5 reaches a Benoni structure and may transpose to a mainline Benoni if White later plays c4. But in some lines White may profit from not having played c4, e.g. by posting a strong knight on c4 instead.

So you are giving White a pleasant choice, and you don't really gain anything in return. If you are prepared to play the Sicilian, then why not meet 1.e4 with c5 straight away? Sure, White could choose some Anti-Sicilian line, but most true Sicilian players feel that these are not as challenging as the Open Sicilian, so they have no need of a move order that tries to trick White into playing the Open Sicilian.
Additionally, the Benoni is of course far less popular than the Sicilian, which is another reason for your move order being played so rarely.


Learning the hypermodern style Which openings and middle game tactics are highly used when a player utilizes a hypermodern style of gameplay? What particular tactics are most effective when playing hypermodern?

One of the early pioneers, if not the actual founder of the Hypermodern style was Richard Reti, early in the 20th century. An example of this kind of play is his own Reti Opening.

The theory behind this is that center pawns on the fourth rank (or further) can become weak as well as strong. So the idea is to move out knights first, then pawns to the third rank, followed by bishops, etc. Then wait till the opponent commits his pawns to (his) fourth rank (your fifth) before deciding when to move yours to your fourth rank.

An "extreme" example is Alekhine's defense, when Black plays 1... Nf6 in response to 1. e4, to provoke further White advances, and (presuambly), weaknesses. The disadvantage to Black of moving the knight around seems to offset whatever disadvantages White may incur by advancing his pawns. Alekhine's Defense variation, understanding white's overextended pawns, black's multiple early knight moves

But if White opens 1. Nf3, he deters ...e5, and limits Black to playing ...d5 (or ...d6, if he wants to enforce ...e5). Hence, "hypermodern" openings beginning with knight moves seem to work better for White, who has the advantage of the first move. This advantage does give White a number of options, including playing "colors reversed" openings with an extra move that Black doesn't have.


How do you analyze master games? One of the pieces of advice (usually from masters) that I see over and over is that I should be analyzing master games. But how do I do that?

Most of the tactics are over my head (obviously the simpler ones I can see). I can see strategical ideas all over the place, but my ideas are probably wrong. Without someone walking me through what to look at it's hard to understand.

What should I be looking for? What should I look to learn?

It really depends on where your skill level is at. If you play rated Federation chess or happen to be buzzing around your favorite online server, you'd probably fall into a rating class or have a rating that serves as a great predictor of your skill/strength level.

With that being said, here's a category-based answer to your question (using the USCF classes and typical online server ratings).

( I'm only going up to class C as I'm currently a B player who's done his time climbing the ladder => is therefore somewhat qualified to make these recommendations :) )

USCF E (1000-1199) or 1200-1400 ICC/FICS with Slow Time Controls:

Avoid just looking at Master games with no textual explanations.  There is ZERO value for somebody at your strength level.
Avoid game books that contain no annotations/text descriptions for each move.
Avoid player game collections (e.g. My Best Games - Vishy Anand) and focus on the few Instructional + Annotated game collections out there.
Totally avoid any book containing games played AFTER the 1900s.
Avoid game books that don't print out a diagram every 2-3 moves.
Always go over the game with a board or a computer.
A lot of these books mean well but often drown you in a ton of variations. It is fine to skip over this part and just get to the move that was played! :)
If you are using a computer, keep the engine off. You don't need it at your current strength level.
Get used to covering up the next move and playing "guess the move". You'll want to do this for every game you ever look at going forward.
Pay attention to the opening PRINCIPLES, don't even dare try to memorize openings or worry about the nuances. It really doesn't matter at this stage ... the principles alone are sufficient.
Write things down on paper or use a database application. The minute something feels vague or does not make complete sense to you, write down your question. Don't immediately read the author's explanation. Come up with your best answer. Then .. and only THEN read the text. You'll be able build a great foundation and start thinking for yourself. It will also boost your confidence when your own ideas are in sync with what was played.
Go back to this game a week later  and review it again. It should feel like a grocery store you've visited in another city a year or so ago. You'll feel comfortable but not enough to not notice something or find a new question worth asking.  Review your previously asked questions ... do the answers now seem obvious? If so, you're making progress!
Finally : Always find a strong-er player or ask a credible forum about a position that stumps you. Even some well written instructional books may not completely explain why a certain move was played in a given position.

Recommended Books: A First book of Morphy (Rosario), Chess Master vs. Chess Amateur (Euwe)

USCF D (1200-1399) or around 1400-1600 ICC/FICS with Slow Time Controls:
Same as above, except now:

You can and should use a computer engine to look at other tactical possibilities that the book did not go over.
You can start looking at pre-1950s games, but still avoid contemporary games/the modern era.
Practice finishing off the game vs. a computer from the position at which one of the Masters resigned. For fun, try to win it at blitz time controls! If this is becoming a struggle, seek help from a stronger player to show you the correct technique (which was bloomingly obvious for the Master who resigned :))
There are some very famous games in chess history that every "Russian schoolboy" knows. Google them out and play through them.

Recommended Books: Chernev's Logical Chess and his Most Instructional Games of Chess.

USCF C (1400-1599) or around 1600-1800 ICC/FICS with Slow Time Controls:

Same as above, but you can finally start poking around at what the big boys of modern chess are doing.  You still want to read books that are intended to be instructional, not just a showcase of somebody's favorite games.
You should have a set of pet openings (repertoire). Seeking out games of Masters who play your opening makes sense.
Make sure you now work through the variations those books tend to spit out. They are quite insightful and show you how much calculation is often needed in critical positions.
Focus on players who often play very natural and beautifully elegant games without tons of complexity. (Capablanca, Fischer would be good examples)
Start focusing on the endgame aspect of their games. Especially how the winner strategically transitions into the endgame he WANTS, making the correct piece trades at the right time.

Recommended Books: Weeramantry's Best Lessons of a Chess Coach.


What's the benefit of using books during correspondence games? I'm playing daily games on chess.com and read that it's officially allowed to use books or databases during the game.

My question is: How does it help me getting better (if it's the purpose of this allowance) to use theory sources in daily games?

What you get from the books/databases during your correspondece games is the same as what you get when you read them generally. You can make use of

Opening lines, which become more important as the games get slower and slower
Tactics, which you may encounter during your games
Positional concepts and maneuvers, which play the most important part of a correspondence game
Endgames, though usually tablebases (7-man) are allowed in correspondence games.

All of these (not including tablebases) are allowed because they are simply undiscoverable in a cheating investigation (for example, you can expect perfect opening play from any player), as well as to help you, as you stated.


Kings gambit for white I'm just a beginner at chess and am just starting to get into the king's gambit but there seems not to be much information on this line probably because I'm not very good and the same with my opposition. I'm used to this line

[FEN ""]
1. e4 e5
2. f4 exf4
3. Nf3 g5

and so on but recently I have been running into this

 [FEN ""]
1. e4 e5
2. f4 exf4
3. Nf3 Nc6

I have run through this on Stockfish but I'm curious if anyone could explain the theory behind the next move.

I remember reading about it in an old Chessbase Magazine edition (circa 2010 I believe). They examined a game where White played Bb5 at the right time, pinning the Knight then later exchanging it for weak queenside pawns, kinda like in the Ruy Lopez. I've used this idea fairly often, at least it's another option to Bc4, the normal development move that might later run into ...Be6 in this case, and it's not like exchanging and playing on the queenside is forced then.

If Black also develops their f8 Bishop, c3 and b4 also take space on the queenside, threatens b5 to kick the c6 Knight, and restrict both the Bishop and the Knight's activity.

In any case, there's nothing wrong with taking the center with 4.d4. As the f1 Bishop might want to go to b5 later, the first question to answer is how should the queenside be developed? c3 reinforces d4 and allows a Qb3-Bc4 battery, but Nc3 brings the Knight to a more active position (controls d5 in particular) than Nd2 where it would block the c1 Bishop. Take back the pawn with Bxf4 at some point (if ...g5, h4), and at this point, it should be clear where your light-squared Bishop can or should go.

At that point, White has completed development and has the center, whereas Black has trouble finding active play for his pieces. White should have a slight, lasting advantage, which should be converted in the long term. The rest is up to what themes you want to play around, but keep in mind the Bb5 idea.


What was the biggest chess tournament held in the world? Which chess tournament and venue has brought in the most people in the world?

According to the USCF, the record holder for largest attendance at a rated chess competition is the SuperNationals V with 5335 participants. Link

The SuperNationals III also had over 5000 participants, so this must be the recurring tournament that brings in the most people.


Why do players in the past play much longer tournaments than today's top players? Looking through the history of chess we find tournaments that are significantly longer than today's, e.g.

London 1899 - 15 players, double round robin
New York 1924 - 11 players, double round robin

Today we get tournaments such as:

Tal Memorial 2018 - 10 players, single round robin
Dortmund Sparkassen Chess Meeting 2018 - 8 players, single round robin

For comparison, the players in the London 1899 tournament played a full four times as many games as those in the Dortmund 2018 tournament.

Why such a large difference? Why can't today's players play tournaments as long as those in the past? Alternatively, if they can, why aren't today's tournaments organized to be as long as those in the past?

There is nothing in principle preventing players from long tournaments. Or maybe yes if they are way too long, like the first Karpov - Kasparov match (had to be postponed for health reasons), but these cases are far from the norm.

If we stick to the elite games, I would say that the main reasons why tournaments have become shorter is that there are many more tournaments to choose from! Every organizer wants the best players to play at them, at making the event longer would result in the players occupying a larger fraction of their calendar, so they will either request more prize money or go play somewhere else.

In short, top level chess has professionalized and players will try to maximize their "paycheck"


Opening book for stockfish I am looking for a relatively up to date opening book for stockfish5 chess engine. I do not need it to be created by a stockfish team (only to work together with stockfish).

Up till now the only thing I was able to find is really old book (it was updated during the time of version 2).

Is there anything newer?

This github post has links to polyglot books; the Komodo book looks especially enticing to me: https://github.com/michaeldv/donna_opening_books

Direct link to Komodo downloads: http://komodochess.com/downloads.htm


Detect pinned pieces code This post is a follow up of this one: C++ vs Java Engine move generation performance

My goal here is to improve the performance of my move generator, which finishes perft (start_pos, 6) in 8.5 secs.
That's too slow for C++ code (the same Java code runs in 11 secs).

The bottleneck is the check for validity, which in turn tests if the king is in check. This is running for every move,
and given that most moves are legal, it's a total waste of time. As pointed out by Student T, we should restricted
this test for king in check, pinned pieces and en passant captures.

The king in check or walking to check cases are easy, this post is about pinned pieces  code.
So, the  cpwiki code goes like this:

pinned = 0;
pinner = xrayRookAttacks(occupiedBB, ownPieces, squareOfKing) & opRQ;
while ( pinner ) {
   int sq  = bitScanForward(pinner);
   pinned |= obstructed(sq, squareOfKing) & ownPieces;
   pinner &= pinner - 1;
}

pinner = xrayBishopAttacks(occupiedBB, ownPieces, squareOfKing) & opBQ;
while ( pinner ) {
   int sq  = bitScanForward(pinner);
   pinned |= obstructed(sq, squareOfKing) & ownPieces;
   pinner &= pinner - 1;
}

And here's the code for xrayRookAttacks():

U64 xrayRookAttacks(U64 occ, U64 blockers, enumSquare rookSq) {
   U64 attacks = rookAttacks(occ, rookSq);
   blockers &= attacks;
   return attacks ^ rookAttacks(occ ^ blockers, rookSq);
}

Questions:

a) What is obstructed() doing?

b) After getting the pinned set, how exactly do I use it to test for a valid move?

Thank you all!

A: Let's use bishop for our example. xrayBishopAttacks works if we have the following position:

but it doesn't work if you have this:

The f3 knight is not pinned because there is something else behind it. obstructed takes this into consideration.

B: Once you get the pinned pieces, you can just do XAND to check if the piece you want to move is pinned. If it's pinned, you can't move it.

************** EDIT **************

You won't find obstructed() because it's just a pseudocode function. You're expected to implement pinning in obstructed() yourself.

Forget the pseudocode, you should study Stockfish. Goto https://github.com/official-stockfish/Stockfish/blob/master/src/position.cpp

Find bool Position::legal(Move m) const

Check the following:

// A non-king move is legal if and only if it is not pinned or it
// is moving along the ray towards or away from the king.
return   !(pinned_pieces(us) & from)
    ||  aligned(from, to_sq(m), square<KING>(us));

This is exactly what I'm talking about.


50-move rule: only the last 50 or any consecutive 50? Suppose that, as a result of White's move, there have now been 100 single-moves (50 full moves) since the most recent pawn move or capture. White didn't claim a draw because they're going for the win. Every option for Black's next move is a pawn move or a capture. Does this mean that Black has now lost the opportunity to claim a draw under the 50-move rule?

(Art. 9.3 of FIDE's Laws of Chess (2018) suggests that they have, but I wanted to check. If I've understood correctly, the opportunity does not just occur on the 100th non-pawn non-capture and then vanish forever --- you may claim at any point from the 100th onwards in a series of more than 100 --- but there must be a series of at least 100 including the very turn in which you make your claim. That is, retrospective claims do not stand.)

This question was prompted by my reading up on Art. 9.3 of FIDE's Laws of Chess (2018) to respond to this question.

She can claim a draw. Article 9.3 of the FIDE Laws of Chess, 2018, emphasis mine:

9.3 The game is drawn, upon a correct claim by a player having the move, if:
9.3.1 he writes his move, which cannot be changed, on his scoresheet and declares to the arbiter his intention to make this move which will result in thelast 50 moves by eachplayer having been made without the movement of any pawn and without any capture, or
9.3.2 the last 50 moves by each player have been completed without the movement of any pawn and without any capture.

9.3.2 is the case you describe, where the moves have already been completed. 9.3.1 is the case that counts the move the player is about to make.
Edit: but you link to the other question. In real tournament chess, checkmate would certainly trump this -- checkmate ends the game, so the other player would never get another turn to claim a draw in. But problems are not tournament chess and they use their own conventions, like the famous rule that castling is allowed unless you can prove it isn't.


Why do players resign after accidentally giving their opponent a free queen? Whenever I verse players in Live Chess (30 minutes) on Chess.com, sometimes I am able to threaten their queen because they brought it out too early in the game. In the opening/beginning to midgame, if I threatened their queen with a simple move, and they forgot to move it away or block the attack, and I take their queen on the next move, they resign. Why?

Material (i.e. basically who has more and better pieces) is a very important factor in the objective evaluation of a chess position. The queen is the strongest piece on the board, roughly equal to two rooks or three minor pieces (knights or bishops).

If you really drop a queen in an otherwise equal position you are going to lose 99.9% of the time. Rarely you have situations where you have compensation for being a full queen down, like for instance you have a very strong mating attack or perhaps the queen is bound to protecting a pawn from queening, etc.

If there is no such compensation it is very reasonable to resign. There is not much point (and not much fun) playing a queen down. In fact most slightly advanced players would resign being a minor piece (knight or bishop) down in otherwise normal position (no attack, etc going on).


Can you checkmate with rook vs knight? Is it possible to checkmate if all you have is a rook and your opponent only has a knight? If both of you play without mistakes or blunders?

When you have a Rook & King vs Knight & King then in most cases the Game would be a draw if played with Best play . Now the Person who has got the Knight he is to make sure that the Knight does not get separated from its King . The Rook should try pushing the King either on the 1st or 8th Rank or a-file or h-file. The Opponent King should try centralize himself . If also the King reaches any of the four Corner ranks or files then the Knight should stay close with the King . The Knight always hinders the Checkmate pattern and comes between the Rook & King .

In this kind of play it is the focus & attention of the Knight Player that plays the role because he is to make sure that Knight does not go far from the King where sometimes it gets trapped and the Game gets Lost.


Chess Olympiad statistics I have watched some matches played in the chess Olympiad in Tromsø. The majority of the games I watched, one player played the English opening, and usually he won, I haven't seen any French opening game.

That makes me wonder if there's any site that has statistics about what is the most played opening, what opening has the highest winning rate and so and so forth.

I don't know of any site that specifically does this for particular tournaments. But its very easy to do this yourself! Here's how you do it:

a) Download Scid vs Pc software (http://scidvspc.sourceforge.net/)

b) Download pgn for the Olympiad in Tromso 2014 from TWIC (http://www.theweekinchess.com/assets/files/pgn/olym14.pgn)

c) Open a new DB in SCID vs PC software and import this PGN.

d) Go to Tools > Opening Report

or

Windows > Tree Window

to get the opening tree and the percentages

Here's the output from Olympiad 2014 taken from Scid vs PC:

4.2 Moves from the report position

 Move        Frequency     Score  AvElo Perf AvYear Draw ECO
 1: e4       1649: 43.6%   52.5%  2275  2313  2014  23% B00a
 2: d4       1404: 37.1%   52.7%  2327  2343  2014  29% A40a
 3: Nf3       363:  9.6%   60.0%  2346  2405  2014  24% A04
 4: c4        248:  6.5%   52.0%  2319  2324  2014  27% A10
 5: [end]      45:  1.1%   35.5%  2197  2058  2014   0% A00a
 6: b3         17:  0.4%   55.8%  2329  2202  2014  18% A01
 7: f4         15:  0.3%   33.3%  2152  2127  2014  13% A02
 8: g3         12:  0.3%   66.6%  2411  2399  2014  33% A00t
 9: Nc3         8:  0.2%   62.5%              2014  25% A00l
10: b4          7:  0.1%   78.5%              2014  14% A00p
11: e3          3:  0.0%   33.3%              2014  67% A00k
12: d3          2:  0.0%    0.0%              2014   0% A00j
13: f3          1:  0.0%  100.0%              2014   0% A00b
14: Na3         1:  0.0%   50.0%              2014 100% A00h
15: h3          1:  0.0%  100.0%              2014   0% A00d
__________________________________________________________________
TOTAL:       3776:100.0%   53.1%  2304  2326  2014  26%

4.3 Positional Themes

Frequency of themes in the first 20 moves of each game:
   Same-side castling:             73%    White Isolated Queen Pawn:       8%
   Opposite castling:               8%    Black Isolated Queen Pawn:       8%
   Kingside pawn storm:            15%    White Pawn on 5/6/7th rank:     52%
   Queens exchanged:               40%    Black Pawn on 2/3/4th rank:     34%
   Only one side has Bishop pair:   6%    Open c/d/e file:                50%


Can Black win this bishop endgame? [Title "White to move"]
[fen "8/p3k3/1p2b2p/2pBPpp1/7P/P1P1K1P1/2P5/8 w - - 0 1"]

Computer played 1.c4?after which I played 1...Bxd5!and the pawn endgame was lost for White. I wonder if there was a way for Black to win this game, with best play from both sides?

It seems that member Dag Oskar Madsen was right, ...Kd7!, cutting off the White bishop's access to c8, is the winning idea. The only trap Black must evade is to lose the bishop after ...Ba2. Below is my analysis:

[Title "White to move"]
[fen "8/p3k3/1p2b2p/2pBPpp1/7P/P1P1K1P1/2P5/8 w - - 0 1"]

1.Bb7 $8 { Every other move lose the pawn on e5. } ( 1.c4? Bxd5 2.cxd5 b5!-+ ) 1...Kd7! { As member Dag Oskar Madsen pointed out, this move offers best winning chances because it cuts of bishop's access to c8 square. Now when Black bishop moves White will not be able to stop Black king to reach e6 and the e5 pawn will fall. } 2.Kd3 b5! ( 2...Ba2 3.hxg5 hxg5 4.c4 Ke6 5.a4! Kxe5 6.Kc3 f4 7.gxf4+ Kxf4 8.Bd5 $8 g4 9.Kb2 Bxc4 10.Bxc4 Ke4 11.Kc3 g3= ) 3.Ke3 $8 { Otherwise Black plays Bc4+ and gets time to play Ke6, winning the e5 pawn and with it the game. } Bc4 4.Ba6 Ke6 5.hxg5 hxg5 6.a4 Kxe5 7.Kf2 { There is no need to fear axb5 because White can not keep that pawn in the long run because his bishop is badly placed. White will need to reposition the bishop in order to fight Black passed pawn, after which Black bishop takes the b5 pawn. } Ke4 8.axb5 Ke5 9.Kf3 Bd5+ 10.Ke2 Be4 11.Ke3 Bxc2 $17


Resources on chess variants While posting this question, I stumbled on this list of variants from Wikipedia, which I must admit is totally awesome.
I know a few online servers allow a few variants, but am not aware of places where many variants players would gather, which would they be ?
Are there famous clubs for on the board variants play ?
Collections of fairy chess problems ?
This list of fairy pieces is not at all bad, but could use a few more easy-to-understand diagrams, and some art for representations.
I guess there's enough to say on this topic for books to be published on the subject ?

Unfortunately I don't know of a chess server where they play chess variants, (see update below) but I have a few other resources.

The program Winboard has several variants, including Shogi, Xiangqi, Shatranj and Atomic.

I also found a very cool blog, the guy there goes over a lot of chess and checker variants.  Its pretty cool!
Here is a article he has about Fairy Chess.

There are also several books written on the subject including:

Chess Variants & Games
Popular Chess Variants

And the Encyclopedia of  Chess Variants

Update
In my ramblings I ran accross this page, indicating that the ICC allows chess variants.
Quote:

  ICC offers a number of chess variants.

I also found a book on Fairy Chess. Unfortunately it appears to be out of print.


Can white still win this? Is it possible for white to turn the tables and win this game or is it "almost" over?

[FEN "1r4k1/2p2pp1/5r1p/p1p1p1bq/P1PpP1b1/1P1P1NP1/2N1QPKP/1R1R4 w KQkq - 0 1"]

1. Nce1

What would you do if you were white?

White can do nothing right now, because he made the last move (Ne1). Black can simply sacrifice the exchange on f3, keeping the pin intact, and aim the other rook at f3. Then, White's position will collapse entirely.

There's no way White can escape the pin, e.g. after h4, Black can just ignore the attacked bishop:

[FEN "1r4k1/2p2pp1/5r1p/p1p1p1bq/P1PpP1b1/1P1P1NP1/4QPKP/1R1RN3 b - - 0 1"]

1... Rxf3 2. Nxf3 Rb6 3. h4 Rf6 4. hxg5 Bxf3+


Suggestions for endgame training I am an unrated player. I am looking for ways to improve my endgame. I am currently using:

Dvoretsky's Endgame Manual
Pandolfini's Endgame Course

(I am personally finding the former to be tough. So I am planning to revise the second first).

So here are my questions:

Please inform me about other sources I should check?
I have heard about endgame table bases on several occasions. But I felt them to be too much information and not enough wisdom. So I have ignored learning more about them. Please advise me about how to have a systematic principled way of assimilating the endgame tables.
I want to read more about mathematical expositions on chess. I am familiar with works of Shannon and Victor Allis. I want to read what Combinatorial game theorists have to say about chess. I for example know about this research group at UC Berkley. Please share if you know any interesting lead along this direction. (I am aware these efforts digress from the real problem of playing tournaments, but I am of the opinion these would help make a stronger player. Please tell me what do you think).

Thanks!

The kind of book you need depends on your level and what you are looking for. Dvoretsky's book is of high quality, well-researched, magnificently analysed and ... pretty much useless if you are under 2400. Well, OK, maybe not useless, but I prefer my chess study to be a little more enjoyable than studying advanced theoretical mathematics.

For something more engaging and accessible, I prefer "Fundamental Chess Endings" by Karsten Muller and Frank Lamprecht. It covers the same topics as Dvoretsky, but with less emphasis on highly theoretical analysis and more on problem solving and practical considerations. But I'm below 1600, so my needs may be different than yours.

End game tablebases, as far as I know, is a complete tree of chess positions that have been solved using a brute force technique by evaluating every possible move. There is no practical way for a human brain to remember the terrabytes of data that it contains for use in OTB games. It would be like learning to play Call of Duty by simulating every possible action of every possible player. The data will only be interesting to people trying to create bots.