He has two queens. I have one. Is it proper chess etiquette to check him non stop just to avoid losing?

What you are describing is Perpetual Check: http://en.wikipedia.org/wiki/Perpetual_check

It is covered in the rules of chess and the result of such a game is a draw. It is up to your opponent to try and avoid this situation if he thinks he can win. Conversely, if you might lose you should try to get into some kind of draw situation to avoid a loss.

Anecdote: A queen vs. queen, knight, and bishop did the same thing at the club quick tournament last night.


What should be defined as an en passant checkmate?

After some research I could not find  any "official" definition by a chess association/federation. This doesn't really surprise me, as there really is no need for a definition of "e.p. checkmate" to ensure correct play.

However the general internet consensus on the usage of the term seems to agree on the following requirements:

The game has to end with checkmate.
The last move has to be played en passant.

An exemplary notated move would be "29... cxd e.p. #" (although notating e.p. is optional under the FIDE laws of chess (C.9)) - regardless if the pawn capturing delivers check or not. The Wikipedia examples follow this definition.

As there is no opinion by a regulatory instance about this topic, it seems to be up to you to make up your mind on this topic or bringing it to the attention of said regulatory instance. I am taking the "democratic" approach with the above definition.


How much of the Principal Variation can I trust?

The answer is, of course, it depends:

Sometimes the engine will accurately calculate a very long sequence of forced moves and all of it will be correct (the more powerful the engine, the most likely this is to happen)

Other times, not even the first move will be correct. It may also occur that the computer plays "correctly" but still gives a wrong evaluation (this is often the case in positions with fortresses)

In summary, your question is too broad, as the answer will vary too much depending on what software you are using, on which machine it is running, and most importantly, what position they are evaluating.


Is Fritz 15 a better chess software than Deep Fritz 14?

While I'm not sure what exactly Fritz 15 will offer (because it hasn't been released), but it's almost certain that there will be a "deep" version. Look at this ChessBase online search, so it's pretty safe to assume there will be Deep Fritz 15. My suggestion: wait for the upcoming version.

However, I don't think Deep Fritz 15 will offer you anything that Deep Fritz 14 doesn't. If we're talking about the user-interface experience, there shouldn't be much because ChessBase always ship an almost-identical software every year.

The most obvious change is the engine, unfortunately, this is not very interesting because Fritz is quite far behind Stockfish and Komodo. If you're looking for the strongest possible engine to study opening theory, you might as well download Stockfish and use it with any compatible client. It's free and plays better chess than Fritz.

You'll need to decide what exactly you want: an easy but expensive bundle from ChessBase or the strongest free chess engine.

EDIT (after product release)

It's nice ChessBase finally drops the "deep" term and it makes perfect sense, who is still using 32 bits in 2015? There is no Deep Fritz 15, just Fritz 15.


What is the fastest way to reach a position in which one side is forced to choose between checkmate and stalemate?

12 moves (24 plies), adapting Loyd's classic 19-ply help-stalemate:
[FEN ""]

1. d3 a5 2. Qd2 Ra6 3. Qxa5 h5 4. Qxc7 Rah6 5. Qxb7 f6 6. Qxb8 d6 7. h4 Bf5 8. Rh3 Kf7 9. Qxd6 Bh7 10. Qe6+ Kg6 11. f4 Qxd3 12. Kf2 Qg3+

and White must choose between 13 Kxg3 stalemate and 13 Rxg3 checkmate.


What does "half-K" mean in the USCF tournament rating system?

As dfan mentioned in his comment, K factor, is a factor for changing convergence speed of ratings. When you win against a strong player, your rating converges to your opponents rating, after some consecutive wins, you will have the same rating with your opponent. K factor simply changes how many games you need to converge we can say. Situations where it is used:

High K used, in first few matches of a player, to let the player reach actual Elo quickly
Low K used, in some tournaments which has non-standard time controls
Low K used, in matches between masters, to stabilize Elo changes.

etc.

There is no absolutely correct K value, it's really open to question how fast it should converge. But when it converges slower, Elo points are more stable. When it converges faster, people can reach their actual ratings faster.

I caused a lot of trouble to people just because of this dilemma. I had an initial rating of 1100(for some riddicilous reason, long story). And at the time my actual strength was about 1500. In time, my strength went up to 1900 but my rating was about 1400. Just because of this, my opponents lost lots of points(unfairly). I remember a game when I was 1300 something, and I won against a 2000 player. He lost a lot of points, and was very sad. If I were 1900, penalty would be much more less.


Lc0 is fully compatible with UCI. It's strength depends a ton on what hardware it's being run on. On any hardware (tested down to Raspberry Pi), it will be superhuman (over 2900 elo). With a RTX 2060 ($200ish) it should be roughly even with SF on 8 cores (although you may need to mess with settings a bit to get it there). A 2080ti puts decently (20 or so elo) ahead of 24 cores of SF. The current MultiPV mode is only a display tweak. It isn't weaker, but it doesn't give as good analysis of the non-primary lines. If you have more questions, the best place to ask is probably the Lc0 discord.


First of all you have to distinguish which kind of error you made.

Opening error:

You should definitely study opening theory to avoid opening traps or get bad positions right out of the opening. On the other side when an opponent plays an unusual/bad move, you need to know how to respond and punish this move to get a better position.

Middlegame error:

Have you overseen some tactical possibilities for you as attacker/defender?

-> Try to solve tactical puzzles to get familiar with certain positions. This will also help you to spot tactics more easily the next time they occur.

Have you had the wrong plan?

-> Study positional topics like pawn formations, weak/strong points, etc. in a position and you will find the right plan straightaway.

Endgame error:

When you have no clue how to play certain theoretical endgames you will easily take a wrong step and lose drawish positions or draw winning positions.

-> Take a good endgame book to study some basics.

Also learning from mistakes you make, means you should not make the same mistake again. Thats especially true for opening errors and endgame errors in easy theoretical endgames.


The only variants I can think of that experienced chess players seem to have any interest in are Chess960 (aka Fischerandom) and Bughouse. Even Seirawan chess, which has the imprimatur of a grandmaster, has not really attracted any real interest.

Other variants are not looked on unfavorably but they are basically ignored.


Does playing chess with a real board help improvement more than play online?

I play most (>95%) of my games online, and when I play with a real board, I find a bit difficult to translate positions I already played and the visual pattern matching of tactical situations takes longer. Not to look at the board then, helps a bit.
So, I think, when you prepare for a board tournament, or something like this, preparing on a real board will help. When you only play online all the time, it doesn't matter.


Here is a link with informations you can get on chess program Wilhelm.

http://web.archive.org/web/20081208015339/http://www.geocities.com/rba_schach2000/overview_english.htm

Unfortunately, this chess program by Rafael B. Andrist stopped being developped in 2006.


You'd have some data structure, such as a 2-D 8x8 array, storing the current piece in each square of the board. Everytime you read a new move, update the array appropriately. Then, when you see a capture like "exf5", check what piece is stored in the "f5" square of the array.

You'll have to be careful with en passant captures. For example, in the case of 1.e4 c5 2.e5 d5 3.exd6, you should be checking the element in the array 1 row above (for d5). In order to detect when an en passant has occurred, see if a pawn captured on to an empty square. For example, 3.exd6 is White's e5-pawn capturing on to the empty d6-square, so it must be en passant.


Pros and Cons for black in Queen's Gambit Accepted

A super-abridged guide to the QGA (Queen's Gambit Accepted) is that Black temporarily cedes the center with dxc4, and hopes to develop rapidly while White recovers the pawn (you'll want to look up some key lines where Black suffers because he is greedy and tries to hold on to the pawn; personally, I found it instructive to look at the main line of an entirely different opening called the Noteboom Variation, where Black has better chances to hang on to the pawn, but White's tricks still recover it), and then—just before White can start to cash in on his central advantage—play c5 in an attempt to nullify the center.

For example, a sample line (not necessarily main line; it lacks some "professional subtleties" that, as others said, you really don't need to memorize as a beginner):

[FEN "rnbqkb1r/pp3ppp/4pn2/8/2Bp4/4PN2/PP3PPP/RNBQ1RK1 w kq - 0 7"]
1. d4 d5 2. c4 dxc4 3. e3 Nf6 (3... b5? 4. a4 c6 5. axb5 cxb5 6. Qf3 {Winning White material}) 4. Bxc4 e6 5. Nf3 c5 6. O-O cxd4

In the above ending position, White has the option to either cede the center himself with Nxd4, or give himself an IQP (isolated queen's pawn) where he accepts what could turn out to be an endgame weakness (an isolated pawn) in exchange for a middle game catalyst (the White pawn will serve as a powerful battering ram and outpost provider that Black must stop at all costs).

However, Black will have his work cut out for him trying to actually gain the upper-hand over White, whose spatial advantage allows him to develop relatively more comfortable than Black. If you want something that's a bit less of an "exposed" opening for Black, I might recommend the French or the Caro-Kann which has the same idea of ceding the center only to counterattack with c5 (unfortunately, of course, neither of these are likely with 1. d4).


I suspect you are looking for OpeningTree


Top players move order when playing QGD?

There is no real objective answer, both are playable at any level. Such variations in move order are decided primarily according to roughly 3 common criteria:

a) Comfort zone of the player: which structures they're more familiar with, and therefore, they may opt for lines that maximise the liklihood of ending up in those.
b) The types of variations and transpositions they want to prevent from occurring (depending on the opponent), which itself depends on various elements.
c) The kind of game they've envisaged: double edged, conservative, etc. (this is a subcategory of b) essentially), all of which influence how committal you're going to be with your starting moves.

Therefore, these matters tend to be quite opinion-based, that said, here's an attempt to shed some light on a handful of key differences between the two specific lines:

More particularly for the line you ask about, 1.d4 Nf6 2.c4 e6 3.Nf3 d5 ... often called the anti-Nimzo qualifies as one of the most versatile options for black as there still remain a diverse set of variations for black to consider, to name a few (assuming 4.Nc3):

On the solid side: 4...Be7[*] (leading to mainline QGD with Bf4...e3).
Or sharper variations such as: the Vienna 4...dxc4
Tarrasch 4...c5
Ragozin 4...Bb4

Note that white is also keeping many options open with 3.Nf3 instead of Nc3.

On the other hand, with 1...d5, well for starters, Nimzo Defence options are essentially ruled out, and assuming black is going to follow with e6...Nf6, white is left with early options to divert towards fundamentally different structures such as the exchange variation of the QGD: 1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.cxd5 exd5 5.Bg5 ..., compared to the move order with 1.d4 Nf6 2.c4 e6 3.Nf3 d5 where an attempt to transpose to an exchange variation with 4.cxd5 exd5 leads to poorer version of that system for white as the early Nf3 is almost a lost tempo since black has to pressure d5 (with early Nc3 and Bg5 pinning f6-defender) while including an early Qc2 to prevent black from creating a good light-square bishop with Bf5.
So the whole setup with early Nf3-cxd5 and without Nc3 allows only for a nonthreatening transposition to the QGD exchange variations.

Instead, by not committing to d5 [**] on the first move and playing Nf6, black preserves the option of playing the Nimzo among other lines (and therefore, avoid QG's altogether if so desired), while transpositions to most variations with pawn on d5 remain open, which leads us to the natural conclusion that: not making early committal pawn moves in the centre tends to leave us with more options on the table.

So as you see, all these lines are possible but the decisions are made according to one's preferences (and the circumstance at hand) and neither option (1...d5 , 1...Nf6...) is generally better or worse.

Regarding your last question,

  Also, why is QID via 3. ..b6 almost never played?

it's not clear what you mean, the move 3...b6 is the defining move of the Queen's Indian Defense (QID), and it is frequently played (by e.g. Carlsen, Karjakin, Anand, Ivanchuk, ...).

[*]: This mainline followed by Bf4..e3 and 6...c5 also happens to be what Carlsen - Caruana had prepared for during the recent world championship event, see e.g. game 7.

[**]: Similarly, 1...d5 also avoids certain lines that 1...Nf6 doesn't, but there's not enough time/space to get into that.


Are computers playing good chess beyond what humans can see?

Do the strongest human see any value on those Stockfish-Houdini matches, do they give credibility to what those machines play, or it is simply crap nobody understands?

In many positions, computers play strange moves that no human would ever consider. People refer to moves like that as "computer moves." Some insanely deep tactic to reach a risky position that scores every so slightly higher than an obvious, safe move.

But, it's not crap. These computers playing these moves beat all human grandmasters. That's how we know the moves make sense, the computers would lose if their moves didn't make sense.

It's just that our human way of understanding the game is ultimately limited. Some moves just look like they go against all our understanding of positional play -- but they work. So it's our understanding that is wrong.


Why is the Budapest Defense considered not fully sound or even dubious? What theoretical difficulties arise for Black?

It's definiely not a "bad" option for Black. It can be played at high levels and still get decent results. However, it's not considered a "great" line for many reasons:

As you said, White has multiple set-ups to choose from most of them leaving them with a slight advantage.
The "surprise factor" that may give Black with an edge against an unprepared opponent doesn't exist (at least not so early in the opening) at the highest levels.
White only enters the Budapest if he wants. If he's worried that his opponent may go for it, he can just play 2.Nf3, most likely transposing later on to his favourite opening.

Database statistics should always be taken with a grain of salt, since there could be multiple factors biasing it (a particular player that uses it very often, or an opening being "the favourite" of weak players, or maybe an opening that is used as a surprise weapon against strong opposition). However I think the factors above prevent the Budapest from being a practical choice to build your repertoire around (specially reason #3: you'll still need something against 2.Nf3, say the King's Indian. You'll be able to use that against 2.c4 too, so you may just as well forget about the Budapest and focus on the King's Indian)


To be fair, I tried solving this manually.

Qb1 works.

Basic idea - We see that the Black king cannot move. All that is needed is to give it a check. But where to give it a check from? The Black queen guards many key squares like h4, e3, c3, e1. Thus, White should try to find other squares. Qb1 threatens mate with Qb4+.

This is what I calculated -

1...exd5 2. Bxd5#
1...e5 2. Qb4#
1...b4 2. Qxb4#
1...h1=Q 2. Qb4#
1...Qxa3 2. c3!#
1...Qe1 2. Qxe1#
1...Qe3 2. Rxe3#
1...Qb3 2. cxb3#
1...Nxg6 2. Qb4#

I also confirmed with a computer that Qb1 is correct.


Live statistics chess960 from chess.com?

Yes, it's possible to obtain the data you want. Chess.com has a REST API which is described in the following news post:
https://www.chess.com/news/view/published-data-api
You can use the following URL to get a list of monthly archives of a players games:
https://api.chess.com/pub/player/{username}/games/archives

In this list you will find URLs which look like this:
https://api.chess.com/pub/player/{username}/games/{YYYY}/{MM}

If you append /pgn to this URL, you will get get all the games in PGN format, which is probably simpler to parse.
Lets look at an example:
https://api.chess.com/pub/player/magnuscarlsen/games/2018/01/pgn
Here you will find games played by Magnus Carlsen in January 2018. This list contains a couple of Chess960 games, which are identified by the following tag:
[Variant "Chess960"]

The following tags will give you the UTC date and time of the game as well as the players ratings at the time:
[UTCDate "2018.01.03"]
[UTCTime "21:50:55"]
[WhiteElo "2706"]
[BlackElo "2940"]

Lichess has also an API to download games, which I already described here.
Code
Here's some simple Kotlin code to extract the data (you will need to change the file and user name):
import java.io.File

fun main() {
    val data = (File("ChessCom_magnuscarlsen_201801.pgn").readText().trim().split("\n\n\n").map {
        it.split('\n').filter { it.startsWith('[') }.map {
            val t = it.replace(Regex("[\\[\\]]"), "").split(' ', limit = 2)
            t[0] to t[1]
        }.toMap()
    })
    data.forEach {
        if (it["Variant"] == "\"Chess960\"") {
            println("${it["UTCDate"]} ${it["UTCTime"]} ${it[if (it["White"] == "\"MagnusCarlsen\"") "WhiteElo" else "BlackElo"]}")
        }
    }
}

Result:
"2018.01.03" "21:50:55" "2706"
"2018.01.03" "21:09:41" "2727"
"2018.01.03" "19:43:22" "2703"


Is use of the gambit the main way for black to win?

You ask whether gambit play is the main way for black to play for a win, but instead of gambit play specifically, the issue is more generally one of unbalancing the position (and this is true regardless of which color one has). Sacrificing material for some other type of compensation is certainly one way to do this, but it is only one of many. Generally speaking, the more unbalanced a position is, the more easily either side can end up playing for a win.

Consider the following two somewhat extreme positions. Position A arises in the Exchange Variation of the Slav Defense after the following moves:

[FEN ""]

1. d4 d5 2. c4 c6 3. cxd5 cxd5 4. Nf3 Nf6 5. Nc3 Nc6 6. Bf4 Bf5 7. e3 e6 8. Bd3 Bxd3 9. Qxd3 Bd6 10. Bxd6 Qxd6 11. O-O O-O

Position B arises in the Sicilian Dragon:

[FEN ""]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 g6 6. Be3 Bg7 7. Qd2 Nc6 8. f3 O-O 9. O-O-O

Note that material is entirely level in both positions, yet Position A is much more drawish than is Position B. In my database, 1264 out of the 1285 games which reached position A ended in a draw, or 98.4% of them! At the same time, only 2829 out of 10788 games reaching Position B ended in a draw, a mere 26.2%.

The reason is that in Position A everything is level: equal material, identical pawn structures and piece development, same-side castling, etc. In Position B, despite the material equality, the position is more unbalanced, in particular via the opposite-side castling, the differing pawn structures, and the fact that each side will need to develop pieces for defensive purposes near its own king and offensive purposes on the other side of the board.

In sum, I think it's a mistake to think that gambits are necessary in order to play for a win with black, any more than it's necessary with white, and instead one should strive to unbalance the position in order to create greater winning chances. But as with gambits, while unbalancing the position can decrease the likelihood of drawing, this is usually by increasing both of the individual likelihoods of your winning or your losing. So by upping your chance of winning the full point, you are also taking on greater risk yourself.

With that in mind, one should always take one's particular opposition into account. For instance, if one player is significantly stronger than another, he or she might even aim for something like Position A (maybe not quite that, but something like it) with every intention of playing for a win, and counting simply on greater skill and the opponent's inevitable mistakes in order to have very high winning chances without taking on any of the the risk of Position B, wherein the stronger player could have a bad day and make a mistake that, in that position, could be serious enough that even the significantly weaker player could then carry the day from the point when the mistake was made.

Even more to the point: despite what I wrote above, it's important to be aware that at the amateur level, absolutely any result can come out of absolutely any opening, no matter how crazy or how lifeless it may seem (or even objectively be). Almost every game at lower levels will involve swings back-and-forth throughout the game, in terms of where the objective advantage lies, as both players make mistakes. So whatever the outcome of the opening phase may be, the game is still there to be had in the middlegame, and then again in the endgame if it gets to there. Thus what is most useful in opening play at the amateur level is aiming for positions that you understand, and that you are comfortable with, as this makes it more likely that you will do better in the middlegame.


Is the bishop pair and a pawn equivalent to knight and a rook?

It's an oversimplification to think of the bishop pair to be worth 0.5 points on average. There are cramped positions where a bishop is barely better than a pawn. It's very difficult to generalize based on your question, it will vary greatly from position to position. But in case you're only interested in an "on average" answer, then the side with the rook has a slight edge.


Is this endgame (sort-of Q vs K) a draw?

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

One of the longest variations given is as follows:

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

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


You can go here: http://www.caissa.com/chess-tools/pgn-editor.php and select the tab "2. Game Moves", then make your moves. The fourth tab will show the fen and the pgn of the game.

As far as where to store them, create a folder somewhere named openings, and save each different set of fen/pgn as a text file with the output.


Structure-better structure or bishop pair in the endgame?

More often than not, the Bishop pair will compensate for doubled pawns in an endgame.
Your unopposed bishop would have to be pretty bad (and therefore your overall position) if it's influence did not compensate.

In general doubled-pawns are not that bad if you have active piece play.  Look at the games from the Kasparov-Short world championship match.  Nigel Short repeatedly had doubled crappy looking pawns but because his pieces were active Kasparov was not able to capitalize on their weakness; this fact was well commented at the time.


How to exercise an opening variation with a chess engine?

Chess engines use an opening book during the opening. The standard way of doing what you ask is to build your own opening book and point the chess engine to that so it uses your book and not the previously supplied one.
When you are done just switch back.


Online or Print Sources for Historical Games

In addition to a handful of games at chessgames.com, you may find the following links useful:

About 35 games played in first international women's chess tournament held in 1897 can be found here. Games are in digitized form, in algebraic notation. The sources of each game (chess magazines of the time) are mentioned at the end of each game. You might be able to find these chess magazine pages at the Chess archeology website or by searching for the name of the chess magazines on archive.org. Using a similar approach, if you know the year in which the women players you are interested in played the tournaments, you can dig the games out from the archived magazines. These games will be in old notation, though.

A nice series of articles on women in chess published in a chess.com blog; contains a few annotated pgn games by women players (including the players you asked in the question).

Also, in reply to a comment you mentioned above (where do chessgames.com get their games from?), you will find the following answer in the FAQ page of chessgames.com:

The database has been constructed over a period of many years from PGN files obtained from free, public domain sources. Primary among these sources are:
* University of Pittsburgh FTP - one of the oldest and most complete archives of chessgames online.
* La Regence - archive of recent chess games, organized by ECO code.
* Britbase - archive of British chess games from the 1920's to present.
* Rusbase - the Russian cousin to Britbase.
* The Week in Chess (TWIC) - Mark Crowther's world famous source for brand new chess games.
* Lars Balzer's Homepage - A very well maintained list of places on the internet where you can download chess games.


What is the maximum Elo rating that Magnus Carlsen could have if he loses the 2014 WCC to Anand?

In a hypothetical situation where Carlsen knew that he was going to lose the match and his number one priority was to preserve his rating points, then his best option would be to lose as quickly as possible. As pointed out in this question (EDIT: Values updated as per JiK's comment below), Carlsen will lose 1 rating points for each game he draws with Anand. The only way that he could extend the match and not lose points in the process would be to win as many games as possible before losing.

Assuming Anand wins with the minimum possible score of 6.5/12, Carlsen will lose a minimum of 17 points (11 draws x 1, 1 loss x 6). This does not change if draws are replaced by a win for either side.

However, if Anand was going to win with a draw and 6 wins, then Carlsen stands to lose
 37 points. If Carlsen somehow knew this would be how Anand would win, then he could attempt to interpose as many of his own wins (up to 5) as possible, ameliorating the loss somewhat. Even in this situation, Carlsen's best result remains a net loss of 17 points.

EDIT: And to answer the question as it is worded in the title: Carlsen's rating (assuming no results outside the WCC match are counted) would be no more than 2863.0 - 17 = 2846.0


This is a very well known problem in chess programming. You should consider use the numbers generated by Pradyumna Kannan. Dr Kannan had kindly produced open-source the magic numbers. It is being used by Crafty and a few other chess engines including my own.

You can read more by google "Crafty magic number".

I've prepared a zipped file for you here. This is the same files being used in the SmallChess chess engine app. Please read the documentation. Basically, you'll need to call Rmagic(square, occupancy) for rooks and Bmagic(square, occupancy) for bishops. You can XOR those into a queen mask.


Is there a database of endgame positions with known perfect play?

Yes, it is call Lomonosov table : link

It is all the positions with 7 or less pieces and the whole answer is known.


Is there a way to get MANY and FAST (but not deep) position evaluations in javascript?

Stockfish JS is a Javascript port of the Stockfish engine. It should be useful for your project. You might want to learn the UCI protocol.

Hint:

Use Stockfish JS. Consider:

Send MultiPV for a position. You will get an evaluation for the moves.

OR

For n legal moves, play them one by one. Ask Stockfish for an evaluation on each of those possibilities.

The second approach is slower but more accurate. If you just want shallow search, try the first one.

If you could multithread, do it. If you could run positions independently, do it.


What is the result of this pawn-endgame with perfect play by both sides?

Analysis of this general endgame appears in Staunton's Handbook, in the section "King and Three Passed Pawns against King and Three Passed Pawns."

In the preceding section of the book, "King against Three Passed Pawns," Staunton provides analysis indicating that a lone king battling the three connected passers in isolation (without assistance from their own king) can stop a promotion by getting to the so-called master square, which are here g3 for White, b6 for Black.

When considering these KPPP vs. KPPP endgames, he asserts a general rule about the kings' starting points for those positions in which one or both kings are within 3 squares of their respective master squares:

  Victory will be in the hands of the party who can first play his King into its master square.

Staunton goes into some detail explaining the general logic behind play, and gives some examples. I won't try to elaborate here, but instead refer the reader to Staunton's text if interested. According to the rule, the OP's position would indeed be a win for White.

Among the examples Staunton considers, one is "Greco's position," which is identical to the OP's but with kings on e1 and e8. According to Staunton, that position was long considered drawn, but analysis given by Szén revealed it to be a win (in accordance with the rule above). Staunton further considers the position with kings on d1 and e8, calling it "Szén's position," and presenting analysis he credits to Evans (consistent with bof's comment to the OP) showing this also to be a win for White (again in accordance with the master square rule).

For those interested in more beyond Staunton: there is a paper by Noam Elkies applying combinatorial game theory to chess endings, and which in particular considers cases where pawn endgames essentially reduce to distinct subgames wherein mutual Zugzwang might arise. It deals with some of these KPPP vs. KPPP endings near the end, including Szén's position and a nice study by Behting:

[fen "1k6/1P6/2P5/P7/5ppp/8/6K1/8 w - - 0 1"]
[White "White"]
[Black "to Win"]


To expand BKFM's comment, this article says:

  Verdoni, dessen Vorname und Geburtsjahr unbekannt sind, soll
  italienischer Herkunft gewesen sein. Sein schachliches Wirken vollzog
  sich in Paris und später in London.

This translates loosely as " Verdoni, whose first name and date of birth are unknown, was of Italian stock. His chess career was in Paris and later London."


What makes chess engines so good at chess?

Engines do use opening and endgame databases to help their play but that is only a small part of their strength. The strength of the engines come from what they do while they don't have a database move. The strength of engines come basically from two factors: evaluator and search.

The evaluator assigns a value to a position so that the search will know which positions to favor. Most engines nowadays evaluate on the order of 1 million positions in a second, so the evaluator needs to be fast. The evaluator may take into account for example material, pawn structure, king safety, mobility, just to name a few features. In state of the art engines, the parameters of evaluator function (i.e. how much a feature affects the total evaluation of the position) are tuned using thousands and thousands of CPU hours of testing.

As you mention, the number of possible variations grows very rapidly. The average number of moves in a position is around 35, so the number of positions already after 6 half-moves is more than one billion, which is clearly infeasible.

A simple improvement is using the alpha-beta search, which is based on the observation that, for example, if you have calculated that move 34.A wins a pawn, and you know that after move 34.B Black can reply 34...C after which White does not win a pawn, you don't have to check other responses to 34.B because clearly you already know that 34.A is better than 34.B. If you have a good heuristic such that best moves are always searched first, this reduces the number of positions required to search depth d to sqrt(35^d) instead of 35^d which is a huge improvement. Transition tables reduce the search tree even more.

But this is not even close to what top chess engines really can achieve! Using some smart and smarter tricks to decide which nodes (=positions encountered during the search) are important and which are not, they search some parts of the search tree deeper and cut some parts early, which allows them to reach depth d for important variations often in even less than 2^d nodes. A quite technical list of possible ideas for selectivity is given in the Chess programming wiki.


Is the FIDE International Organizer title required to organize high level FIDE tournaments?

It looks like the answer is "No" because Arkady Dvorkovich, who has no organizer title, was the chief organizer for the FIDE Grand Prix Series Riga- 2019, FIDE Grand Prix Series Riga- 2019 Blitz Tie-breaks and FIDE Grand Prix Series 2019 Rapid Tie-breaks tournaments.

However there is an additional paid position for "FIDE World Events" called a "FIDE Technical Director". The role is described here.

  FIDE Technical Director (FTD) is the overall observer of a FIDE
  World Event
  The FIDE Technical Director FTD is appointed by FIDE and must be a licensed International Organizer
  Main duties of the FIDE Technical Director"

  To be responsible for the communication with the Organizer after the approval and circulation of the tournament regulations.
  To check before the start of the competition if the organization adheres to FIDE standards.
  To check if the Organizer provides to the participants the conditions offered in the bid and described in the event invitation.
  To be contacted by the National Federations as the FIDE Representative.
  To ensure the contact of the competitions according to FIDE rules and regulations
  By the end of the competition to send his report to FIDE including and comparing the final evaluation with the bid-evaluation.

  Organizer provides the following conditions to the FIDE Technical Director:

  Single room (FB- 3 meals) 2 days before the start of the competition till departure
  Air-travel expenses & transportation to the venue

  FIDE pays to the FIDE Technical Director the stipend in accordance with the Financial Guidelines for the Technical Officials.


How can I learn combinations without a chess book?

Chesstempo has a tactics trainer with solving against the clock and a tactics rating. I think there are a bunch of other sites out there with similar features.

If you are rather old school WTHarvey has 10,000 chess puzzles, just as a collection of diagrams with mouse over solutions.

Chessgym also has tactics against the clock and some other features like playing endgame positions against tablebases.


Where is there a mate in four (pawn moves)?

1.d6+ Ke8

2.e6 a4 (pawn move 1)

3.Kf6 a3 (pawn move 2) [Note: 3.e7 Kf7!]

4.e7 a2 (pawn move 3)

5.Ke6 a1=Q (pawn move 4)

6.d7 mate


Sadly, yes. There were times I installed Windows just because of playchess.com doesn't support other operation systems. Your options are:

Installing Windows

with boot camp
in a virtual machine

Installing a compability layer

Wine (free)
Crossover (commercial)

Helpful links

http://www.howtogeek.com/187359/5-ways-to-run-windows-software-on-a-mac/
http://www.davidbaumgold.com/tutorials/wine-mac/


Did Kasparov refute over the board Karpov's 1987 novelty?

I recall these games from his Modern Chess series. Logically, if Kasparov was willing to return to the same position, Karpov believed that it was likely that Kasparov had found a line that resulted in a favorable position for White. Indeed, the moves 10. d3 and 11. Qb3 give White some advantage and Kasparov had a rather pleasant position throughout. Karpov probably didn't want to revisit this line as he knew he got lucky in the first game.


What is the piece value heuristic in atomic chess?

The answer is, as expected, "it depends". To answer directly first, 2016 Atomic World Championship (AWC) winner, tipau, put the values as:

Pawn - 1
Knight - 1.5
Bishop - 1.5
Rook - 3
Queen - 6

As a somewhat strong player myself (two top-8 finishes in the AWC) who has extensively analysed atomic chess endgames, I would tend to agree.
The king has no value, but outside of stopping passed pawns in endgames and a few other special zugzwang compositions, it is almost useless.

Now to go deeper into the topic, do note that the piece values change during the game. General experience would give the following points to support the piece values:

In an endgame, a minor piece is only slightly more than a pawn; if one side has N pawns + 1 minor piece while the other side has N+1 pawns, the side with the minor piece has a slight advantage (which may not be enough to win, depending on the position).
In the middlegame, a minor piece is worth more than a pawn, but usually less than two pawns.
A rook is generally worth more than a minor piece, especially when there are more open files for invasion. A minor piece + pawn can compensate for a rook in the endgame though, generally forcing the side with the rook to take a draw by perpetual check.
Knights are generally better than bishops in the very early opening and endgame, but not in the middlegame.
The bishop pair is much stronger than the knight pair or a knight + bishop.
The queen's value is hard to pin down. Depending on the position, she can be worth less than B+N, or more than R+B+N+P, as seen in several common opening lines. It largely depends on the solidity of both sides' positions.
Factors like piece activity, pawn structure, passed pawns and other non-material considerations also matter in any given position.

I would therefore recommend using the following rules of thumb instead of exact point values:

B ~ N (depends)
N/B slightly > P
B+B > 2 minors
R > N/B
R ~ N/B + P
R > P+P
R < B+N
Q somewhere between B+N and R+B+N+P


Why did Carlsen play 7. dxc5 in Game 7 of the 2018 World Championship?

The same move order also occurred in game 2 (at least up to 9...Qa5). It's a good question that you're asking, though I'm afraid there's no intuitive answer in the way that you're looking for. Instead, these are very concrete lines well polished by computer analysis, which means the best way to understand a decision such as 7.dxc5 is to simply play through the lines a bit, and consider a couple of alternatives in order to draw close analogy between these QGD lines and pinpoint the main differences with and without dxc5.

That said, part of the answer also simply lies in the strategies that the players have adopted in this match (which ultimately stems from their exact preparations), e.g., Caruana seems to favour these rather more solid lines with 4...Be7 as opposed to the somewhat sharper variations such as the Vienna (4...dxc4), Tarrasch (4...c5) or Ragozin (4...Bb4) to name a few, most of which by the way Caruana has himself played previously. But then 4...Be7 essentially allows Carlsen to stay in the mainline theory of QGD with Bf4 and e3..., and from Caruana's point of view, it's the 6...c5 variation that he seems to have chosen to prepare for and play in this match against this line (so you should remember the line as Be7... c5, as the key defining moves of this variation), which he has followed similarly in both games with this Nc6 and Qa5-Rd8 or Qa5-Qd8 ideas.

Now here's my attempt to offer you a bit of intuition for the specific 7.dxc5 variation, but do take it with a grain of salt as these (like most other Queens pawn openings) are inherently very concrete lines after all: (annotations added to all variations and sub-variations)

 [title "London WCC2018 7.dxc5 in QGD games 2&7"]
 [fen "rnbq1rk1/pp2bppp/4pn2/2pp4/2PP1B2/2N1PN2/PP3PPP/R2QKB1R w KQ - 0 7"]

 7. dxc5 {What it achieves in short: i. leaves the bishop slightly misplaced on c5, often it has to return to e7 again e.g. to reroute to f6, or to side-step a3-b4 ideas. ii. prevents black from taking on d4 which would further enable black's development as white is essentially forced to recapture with a piece. On the same token, it keeps the knight on f3 where it is well placed controlling e5 and ready to re-route via d2 if needed. iii. Semi-opens the d-file with ideas to quickly play Qc2 Rd1 with immediate pressure along d-file, where d5 pawn still stands.} Bxc5 (7. Be2 {Let's make a quiet move and see what happens if we let black take on d4} cxd4 8. Nxd4 (8. exd4 dxc4 9. Bxc4 b6 {One line among others after exd4. But it already exemplifies why exd4 is bad for white: to play for any edge white has to maintain their IQP but black gets then an easy development with early b6 Bb7, target on d4 and a somewhat misplaced bishop on c4 which can be exploited to gain tempo. If white decided to resolve the IQP immediately it would lead to a completely liquidation of most pieces ending in a completely equal game.}) Nc6 {Thanks to the knight on d4 the Nc6 move comes somewhat with a bit of tempo as it forces white to react:} 9. Nxc6 bxc6 {and black has a solid grip over the centre, and partly solved their bad c8 bishop problem as now there are ideas to trade via a6, that is, Qa5 Ba6 ...} (9. Nf3 Qa5 {or dxc4, and black even has a slight initiative, Nf3 back is clear tempo given up by white.})) 8. Qc2 {As opposed to the more fashionable lines, namely cxd5. Qc2 side-steps the d-file to avoid queen trades and free the file for a quick rook move. Prophylactically stops Bf5 in certain lines because white will be ready to face it with Bd3, e.g. after Qa5 Re8 e5 Nd4 Bf5. It also controls e4 stopping any possible early Ne4 by black, and avoids immediate material trade that is common to cxd5. Finally, it also x-rays the bishop on c5 which is unprotected, forcing black to react to the potential discovery attack.} (8. cxd5 {still rather famous line, previously played by many including Carlsen, MVL, Grischuk, Caruana.} Nxd5 9. Nxd5 exd5 10. Bd3 Bb4+ 11. Nd2 {10. a3 also possible. And black is fine structurally because even the IQP is not permanent as d4 is playable in many lines that follow. But black has a somewhat slow play, because bishop is misplaced on b4, often it reroutes to f6-b2 diagonal via e7, and black still has to play Nc6 and develop c8 bishop. So it's decent for white but more committal which is maybe why Carlsen is not opting for it.}) Nc6 9. a3 {Still a highly theoretical line, still evolving as Carlsen and Caruana have been showing in the match so far, but it's one that suits both their styles of having a closed positional QGD game, with various continuation choices left for both sides.}

Hopefully, the above analysis (by no means exhaustive) offers you a glimpse of the kinds of ideas that underlie the dxc5 line. But bear in mind that, in general, to answer such questions for yourself, try to uncover not only the concrete aspects of what the move achieves, but also the sorts of ideas it prevents or side-steps.


Touch move rule when the opponent is not present on the board

Article 4.3 of the FIDE Laws of Chess (the touch-move rule) also applies if the opponent is not present. But let's split your question up a bit:

  Imagine this situation, the opponent is not present on the board (far
  away), you touch a piece and the opponent (or somebody else) claims
  that you have to move that piece, can you deny it?

In dubio pro reo. (When in doubt, for the accused.)

Unless there is any other evidence (e. g. the arbiter or a spectator observing you), if you deny having touched a piece, the arbiter should declare that there is not enough evidence to support your opponent's claim (the burden of proof is on the claimant).

Not admitting that you touched a piece when you have in fact touched it, however, is one of the most immoral things you can do in a game - exactly because of this issue.

  My idea is, while the opponent is not present on the board, it is OK to touch the pieces, but does the rule have anticipated this situation?

I would suggest a different approach that avoids all confusion: Call the arbiter to your board and tell him you intend to correct the position of some pieces - that's what the arbiter is there for. If no arbiter is in sight, a more practical approach would be to say "I adjust" clearly while e. g. making eye contact with a neutral bystander to make sure you can prove you did not intend to move a piece.


Did Stein really ridicule Fischer for grabbing the poisoned pawn in the Najdorf Sicilian?

Although it is hard to prove a negative, I don't believe that Stein ridiculed Fischer for taking the poisoned pawn. My evidence is:

An analysis on Chess.com of game 11 claims to source commentary of Stein's and others from Fischer-Spassky 1972 From a Soviet Point of View. Although I cannot find the original source, the commentary quoted on Chess.com is fair and balanced. In fact, 8...Qxb2 doesn't even receive a dubious mark
Googling leonid stein ridicule picks up no relevant articles on the first page
According to the Chessmaster database, Stein's co-comentators Bronstein and Korchnoi had grabbed the poisoned pawn before. I don't think that Stein would have been critical of a move that other top players had played before in a well analysed opening


There are a number of rules for what constitutes a proper problem / study which are extremely unlikely to be satisfied by a position arising in a real game -

there must be only one solution
there must be no superfluous pieces - i.e. if any piece is removed then the solution no longer works or is no longer unique

Sometimes positions arise in a game which come close, usually when there is only one solution which is also rather difficult. Then the position is called "study like" but usually not all pieces on the board are essential.


How to play against the inverted Philidor opening with Black

The basic idea with ...d5, ...Bc5 is just to gain some centre space. I wouldn't really compare this position's plans to the Italian, as they're not that similar. Black's pushed ...d5 early on, and the opponent's (White) knight is on d2 instead of c3.
Analysis for 8.b3: one move for Black in the database is 8...Re8 (or 8...Qe7), supporting the e5-pawn. Now playing ...d4 is an idea, since cxd4 can be answered with ...Nxd4 (as the e5-pawn won't hang). In the case of 9.Bb2, 9...Bb6 10.Re1 Bg4 11.Qc2 Qd6 looks nice for Black. Pushing ...d4 at some point is still in the cards. Black could also consider some ...Qc5 move, pinning the c3-pawn and targeting the f2-pawn. Adding more pressure on the d-file with ...Rad8 looks reasonable.
Analysis for 8.Qc2: 8...Re8 9.b3 could be met with 9...Ba7 (or 9...Bb6), preventing White's queen from x-raying the bishop. This makes ...d4 safer to play. After 10.Bb2 h6 (stopping Ng5 if Black decides to play ...Be6 at some point) 11.Rfe1 Qd6 12.Bf1 Bg4, we have a similar position to what was reached for the line looked at in 8.b3. The plans are similar to what they were there.


Bobby Fischer Teaches Chess - Visual Teaching of Chess

Since you have yet to receive any answers involving books, perhaps my earlier comment may serve as an actual answer: these days, for those like yourself working through obstacles like severe dyslexia, there is an ever-growing body of video-based chess instruction materials that could be well-suited visual alternatives to typical chess book fare.


The match with Kasparov was very close - 3.5 - 2.5 and it is arguable that Kasparov's loss was due to psychological factors. Until Carlsen's recent disastrous tournament where he went to pieces psychologically after over stepping the time control in round one I would have said that Carlsen is psychologically stronger than Kasparov but now I'm not so sure.

Modern day players like Carlsen have closed the gap that existed between Kasparov and the rest without opening up a big gap. I want to say that Carlsen would beat Deep Blue but I suspect the truth is that it would be a close match again.

Deep Blue was dismantled and parts of it can now be seen in two different US museums - http://en.m.wikipedia.org/wiki/Deep_Blue_(chess_computer).


Automatically claiming draw when low on time

I'm wondering if there is something of the sort for on the board games

The closest thing to this according to the latest FIDE Laws of Chess is article 9.6:

9.6 If one or both of the following occur(s) then the game is drawn:
9.6.1 the same position has appeared, as in 9.2.2 at least five times.
9.6.2 any series of at least 75 moves have been made by each player without the movement of any pawn and without any capture. If the last move resulted in checkmate, that shall take precedence.

However this process is not automatic. For either of these scenarios to play out then either the arbiter has to be watching and counting or the moves have to be recorded by at least one of the players and then brought to the arbiter's attention.
In general a game is drawn after 3 repetitions or 50 moves without a capture or pawn move only if one of the players makes a valid claim backed up by a recording of the moves.
See:

9.2.1 The game is drawn, upon a correct claim by a player having the move, when the same position for at least the third time (not necessarily by a repetition of moves):
9.2.1.1    is about to appear, if he first writes his move, which cannot be changed, on his scoresheet and declares to the arbiter his intention to make this move, or
9.2.1.2   has just appeared, and the player claiming the draw has the move.

and

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 the last 50 moves by each player 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.

but note:

9.4 If the player touches a piece as in Article 4.3, he loses the right to claim a draw under Article 9.2 or 9.3 on that move.

So, you can't retrospectively claim a draw under 3 fold repetition or the 50 move rule.
Note that if there are no increments then in special circumstances you may be able to claim a draw when low on time in endgames like KR vs KR.
Here is what the rules say:

III.2.1 The Guidelines below concerning the final period of the game including Quickplay Finishes, shall only be used at an event if their use has been announced beforehand.
III.2.2 These Guidelines shall apply only to standard chess and rapid chess games without increment and not to blitz games.

Important to note that these rules never apply to blitz games, only standard and rapid. Also important to note that they only apply if announced beforehand. This will rarely happen.
Then:

III.4 If the player having the move has less than two minutes left on his clock, he may request that an increment extra five seconds be introduced for both players. This constitutes the offer of a draw. If the offer refused, and the arbiter agrees to the request, the clocks shall then be set with the extra time; the opponent shall be awarded two extra minutes and the game shall continue.
III.5 If Article III.4 does not apply and the player having the move has less than two minutes left on his clock, he may claim a draw before his flag falls. He shall summon the arbiter and may stop the chessclock (see Article 6.12.2). He may claim on the basis that his opponent cannot win by normal means, and/or that his opponent has been making no effort to win by normal means:


How do I make my opening reportorie stronger, specifically my Grand Prix Attack against high level competition?

As resource:

Please check Lawrence Trent's analysis from White's perspective and Andrew Martin's's from Black's perspective.

About line:

I don't find it correct to say anything about this line without studying state-of-the-art. So, you better check experts analyses for suggestions.


How should I defend against this sacrifice in the Two Knights Defense?

I almost always play 4. d4 instead of 4. d3, to keep that line open for the bishop, and open up the game a bit as well. That's not to say d3 isn't ok.

Without computer analysis:
That said, once they make the mistake of sacrificing that knight, you should quickly play Be3 to defend against them double attacking your pinned knight. Once that is accomplished, you can play Qe2 with the plan of castling queenside and evacuating your destroyed kingside pawn structure. Your goal should then be to carefully simplify by trading down until you get to an endgame where you're up a minor piece.

With computer analysis:
Stockfish recommends playing 9. Nd5, with the plan of playing 10. Ne3 for most responses, attacking the bishop on g4 (causing him to retreat with ...Bd7 or ...Be6, probably. The great thing to notice here is that 9... Nd4 is not actually a threat, even though at first glance it appears to lose the knight on f3. After 9... Nd4, White's tactic is as follows: 10. Nxd4! Bxd1 11. Bb5! Qd7 (there is no other option to prevent mate, either 11... Qd7 or 11... c6 12. Nxc6 bxc6 13. Bxc6 Qd7). Bad news for black. After the dust settles it probably looks something like this.

Back to the main line: 9. Nd5. Black can respond with a dozen reasonable moves (...Na5, ...Be7, ...h5, ...Qd7, ...Qc7, ...Qc8, ...a6, ...Rc8, ...a5, ...Rb8), all of which follow with 10. Ne3 (except for 9... Bxf3, in which case 10. Qxf3 is rather necessary). After this, you can start a kingside attack somewhat with Rg1, and getting your pieces out of the way for a castle queenside. You can turn your destroyed kingside pawns to your advantage by starting the attack there. Plenty of options from here on. You end up with something like:

For your second line, after you've already castled, I would not play h3 + g4, which weakens your king's defenses (even if they don't sacrifice a piece there). If you really want to play g4, you can still recover with Be3, defending against ...Nd4. They'll probably bring out the queen to attack (...Qf6), and you need to get your king out of there, undoing your castle to get your rook back outside of the king: Kg2 followed by Rg1 or Rh1. This situation isn't nearly as good for white; you'd be better off just avoiding g4 after castling, at least at this early stage.


Castling long in the King's Indian Defence (for white)

The most common way to end up with queenside castling for white in the KID is via the Saemisch Variation 5.f3. Black often attacks on the kingside in the KID, and the Saemisch is typically a way to avoid that, and ideally to attack on the kingside oneself. Of course, whole books have been written about what's going on in this variation, and I don't play either side of it myself, so this answer only addresses the last part of your question, concerning well-known practitioners.

The link above notes that

  The Sämisch has been played by numerous grandmasters, including world champions Mikhail Botvinnik, Mikhail Tal, Tigran Petrosian, Boris Spassky, Anatoly Karpov and Garry Kasparov.

True enough, and so did Alekhine. But if my database is to be trusted, none of these champions has all that many games on record in the Saemisch, and even less against serious competition. For instance, Karpov played such a setup twice in his 1990 world championship match against Kasparov, scoring a draw (round 21) and a win (round 23), which is a nice endorsement. But he seems not to have played that way often; in my database, the only other classical game for Karpov in this setup against a player who is truly a peer of his is a draw against Timman from round 18 of their 1993 FIDE championship match.

The late Svetozar Gligoric has 18 games on the white side of this in my database (scoring 12.5 points), and his games could be particularly enlightening since he was a well-known proponent of the black side of the King's Indian; in fact, I also see him scoring 22.5/37 on the black side of this, so there's plenty of Gligoric games from boths sides to chew on.

But the most frequent assayer that I find is Florin Gheorghiu, and he's also a very successful one, with a phenomenal 35.5/43 score. So if you want a "hero" to follow for this kind of setup, Gheorghiu might fit the bill nicely. (Or conversely, if you want to know what might be coming at you as black.) To whet your appetite, what follow are two of his wins, each with Gligoric playing black in fact. The first is from the 1966 Havana Olympiad:

[FEN ""]
[Event "Havana ol (Men) fin-A"]
[Site "Havana"]
[Date "1966.??.??"]
[Round "4"]
[White "Gheorghiu, Florin"]
[Black "Gligoric, Svetozar"]
[Result "1-0"]
[ECO "E87"]
[EventDate "1966.10.25"]
[PlyCount "81"]

1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.f3 O-O 6.Be3 e5 7.d5 Nh5 8.Qd2 f5 9.
O-O-O Nd7 10.Bd3 Ndf6 11.exf5 Bxf5 12.Nge2 Qd7 13.g4 Bxd3 14.Qxd3 e4
15.Nxe4 Nxe4 16.gxh5 Nc5 17.Bxc5 dxc5 18.hxg6 Rae8 19.gxh7+ Kh8 20.Nc3
Bh6+ 21.Kb1 Re3 22.Qg6 Qg7 23.Rhg1 Rfxf3 24.d6 cxd6 25.Rxd6 Rf8 26.Nd1
Ref3 27.Qxg7+ Bxg7 28.Rg5 b6 29.a4 Kxh7 30.a5 Bd4 31.axb6 axb6
32.Rxb6 Re8 33.Rg2 Re4 34.Rc6 Rh3 35.Rd2 Kg7 36.Nc3 Re1+ 37.Kc2 Kf7 38.Nb5
Be3 39.Rd7+ Ke8 40.Rb7 Re2+ 41.Kb1

And the other is from the 1968 Lugano Olympiad:

[FEN ""]
[Event "Lugano ol (Men) fin-A"]
[Site "Lugano"]
[Date "1968.11.03"]
[Round "10"]
[White "Gheorghiu, Florin"]
[Black "Gligoric, Svetozar"]
[Result "1-0"]
[WhiteElo "2520"]
[BlackElo "2575"]
[ECO "E87"]
[EventDate "1968.10.17"]
[PlyCount "95"]

1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.f3 O-O 6.Be3 e5 7.d5 Nh5 8.Qd2 f5 9.
O-O-O Nd7 10.Bd3 Ndf6 11.Nge2 fxe4 12.Nxe4 Nxe4 13.Bxe4 Nf6 14.Bc2 Bf5 15.
Ng3 Bxc2 16.Qxc2 c5 17.dxc6 bxc6 18.h4 Qa5 19.Kb1 e4 20.h5 Qe5 21.Nxe4
Nxe4 22.Bd4 Qe7 23.Bxg7 Kxg7 24.h6+ Kf7 25.Rhe1 Rae8 26.Rxe4 Qf6 27.Qa4
Rxe4 28.fxe4 Rc8 29.Qxa7+ Qe7 30.Qd4 Re8 31.Rf1+ Kg8 32.Rf4 g5 33.Rf5
Qxe4+ 34.Qxe4 Rxe4 35.Rxg5+ Kh8 36.Rg7 Re6 37.Rc7 Rxh6 38.Rxc6 Kg7 39.c5
Rh1+ 40.Kc2 dxc5 41.Rxc5 Rg1 42.Rg5+ Kf6 43.Rg8 h5 44.Rf8+ Kg5 45.Rf2 Kg4
46.Re2 Kg3 47.a4 h4 48.a5


Which type of openings generally lead their users not to waste much time on the clock: sharp/aggressive/tactical or positional/solid/quiet openings?

First I would like to preface that both the positional/solid/quiet openings and sharp/aggressive openings can be played quickly without using much clock time by simply being very knowledgeable about your opening.

Quiet openings, particularly systems, tend to require less time. This is because sharp openings are dynamic, that is to say that every move makes a big difference, something big is on the line. Take the kings gambit for example. The opening could quickly become complex white may have a strong attack; black would be advised to use his time because one misstep will cost the game. White also should take his time to make sure that he/she executes the attack effectively.
Quiet openings, even when played incorrectly, will usually only result in a positional disadvantage, which of course is much less devastating than material advantage that often is in the air when we talk about sharp aggressive lines.
In conclusion, sharp aggressive openings, by definitions, require precise calculation in a forest of complexity and tactics. Positional openings require analysis of positional motifs in the position; this usually requires less time than long strings of calculations that sharp positions such as the sicilian often get.
I draw attention to systems, which almost by definition are openings that the user is able to use in almost any situation. Take the london system, for example. This opening can be played practically against all black openings and quickly as well.


Is there retrograde analysis puzzle like "Point on the incorrectly drawn chess piece"?

Raymond Smullyan's Chess Mysteries of the Arabian Knights has some problems where one of the pieces is actually a different piece; you have to figure out which piece.

The problems there which fit this description appear to be these:

3 5 23 28 29 30 39 41 42 43


After 20 ... gxf6 21 Ne4 black is in serious trouble. The threat is 22 Nxf6+ followed by 23 Qh7 mate, and in avoiding this she will have to make serious concessions. An example and not unreasonable line:

[Event ""]
[Site ""]
[Date "????.??.??"]
[Round ""]
[White ""]
[Black ""]
[Result "*"]
[FEN "r4rk1/2p2pp1/pqp2R1p/8/8/P1N5/1PQ3PP/5R1K b - - 0 1"]

1...gxf6 2.Ne4 Rfd8 3.Nxf6+ Kf8 4.Qh7 Ke7 5.Re1+ Kxf6 6.Qxh6+ Kf5 7.g4+
Kxg4 8.Qg7+ Kh4 9.Re4+ Kh5 10.Re5+ Kh4 11.Qg3# *

As a  just below 1900 player I can't claim to be able to see all the variations, but over the board Ne4 is obvious enough to give me enough worries not to take the rook.To see all the glorious details stick it in an engine.


Forced checkmate examples where engines fail

Positing this answer in addition to the answers/comments on tablebases and endgames with ridiculously long forced mates.

White to move and win (I do not know the author of this study, unfortunately). The engines will tend to fail on this and similar problems.
As far as I tried, all recommend to move hxg8=Q. Some show 0.00 and are soon thereafter putting black in a stalemate; some show slight advantage for white and are trying to play the game out by letting black to activate his pieces. Further explanation (and hint to the solution) given in the spoiler block below the diagram.

6r1/p1p1p1pP/P1PpP1P1/8/2P1B3/2K3pp/3P2rq/R5bk w - - 0 1

Explanation spoiler:

   The forced mate is not found because the engines use pruning heuristic. It removes certain branches from search tree, after deeming them as irrelevant to the search result (see: http://chessprogramming.wikispaces.com/Pruning). In case of this puzzle, the solution consists of many subsequent sacrifices and its branch tends to be discarded when searching. Note: Possibly, with tweaked parameters and mate-search heuristic when exact number of moves required is provided, they could find the solution, but I have not tried that.

Solution spoiler:

   Depending on black's move choices, a few solutions exist (the idea is always the same, though and up until move 12 the line is always the same, too). Here's an example: 1. hxg8=N d5 2. Bf3 d4+ 3. Kb4 d3 4. Nh6 gxh6 5. g7 h5 6. g8=N h4 7. Nf6 exf6 8. e7 f5 9. e8=N f4 10. Nd6 cxd6 11. c7 d5 12. c8=N dxc4 13. Nb6 c3 14. dxc3 d2 15. Kb3 d1=Q 16. Rxd1 axb6 17. a7 b5 18. a8=Q b4 19. Be2 bxc3 20. Bf1 c2 21. Rc1 f3 22. Qxf3 Bf2 23. Bxg2+#


Until you reach 14-1500 strength, opening theory is not very important.
One of the best coaches in the world for beginners, National Master Dan Heisman, said:

  It does not matter who gets the advantage out of the opening if one of
  the players is likely to lose a piece to a simple tactic in the
  middlegame. Losing a piece from an advantageous position will almost
  always result in a lost position. So study tactics, not openings,
  until you almost never lose pieces to simple tactical motifs.

However it is good to know the ideas behind opening moves, such as controlling the center, developing, etc.

So 1...Nf6 and 1...d5 are both good moves. They both control the d5 and e4 squares and aid development.


In this famous problem by H. Hultberg (1944), the white king castles to prevent Black from castling:
[FEN "r3k2/1p1p2p1/2pP3p/8/8/5R2/PPPP4/4K2R - - - 0 0 "]

White to mate in two moves.
According to chess problem conventions, castling is presumed to be legal unless it's provably illegal. In this position, you can prove that at least one player has lost the right to castle, but you don't know which one. (If the white rook on f3 came from a1, the white king must have moved to let it out. If the rook on f3 is a promoted piece, it must have visited a8, e8, or f8 before escaping the 8th rank, so the black king or rook must have moved.)
1.Rhf1? fails to 1...O-O-O.
1.O-O! and 2.Rf8#, as Black is now unable to castle.


Why 2.d5 is much less common than other responses to the Mikenas Defense(1.d4 Nc6)?

Just the opinion of a 2000 player.

[fen ""]

1. d4 Nc6 2. d5 Ne5 3. f4 Ng6 4. e4 e6

The idea of this opening, and others like the Alekhine and the Two Knights Tango, is to lure the white pawns forward to make them easier to attack.  Black gets a very cramped game, but it is playable.

[fen ""]

1. d4 Nc6 2. Nf3 d5 3. c4

The main purpose of Nf3 is to prevent black's knight from using that square.  After normal moves, black will find that blocking the c-pawn advance is considered bad.

One of the general objectives in openings is to control the center.  White can attack black's center with the c-pawn, yet black can't support this with his own pawn.  This leads to a small increase in white's advantage.


Sicilian defense : what's the best answer to 2.Qh5?

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

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

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

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


Of course, promoting all the pawns to queens must be done. Creating sixteen passed pawns requires sacking eight pieces, four per side. The sacked pieces should be the knights and bishops to preserve the higher value pieces. From there, it's merely an "Onward, ho!" to a total point value of 182, which comes from the nines queens and two rooks on each side.
Here is one example game in 51 moves, or 102 plies. Since getting 18 queens alone takes 48 moves, or 96 plies, this is almost optimal, I feel.
[FEN ""]
[startply "102"]

 1. c4 f5 2. c5 f4 3. c6 f3 4. b4 g5 5. b5 g4 6. h4 a5 7. Nh3 Na6 8. bxa6 gxh3 9. g4 b5 10. Bg2 Bb7 11. cxb7 fxg2 12. h5 a4 13. h6 a3 14. Bb2 Bg7 15. hxg7 axb2 16. a4 h5 17. a5 h4 18. e4 d5 19. e5 d4 20. Nc3 Nf6 21. exf6 dxc3 22. d4 e5 23. d5 e4 24. f4 c2 25. f5 e3 26. f7+ Kd7 27. f6 e2 28. d6 c5 29. Kd2 c4 30. f8=Q c3+ 31. Kd3 e1=Q 32. g8=Q b1=Q 33. a7 Rc8 34. Rf1 Qde7 35. f7 g1=Q 36. Qh7 Ke6 37. d7 b4 38. a6 b3 39. a8=Q h2 40. a7 Qa2 41. b8=Q b2 42. Qab7 c1=Q 43. a8=Q Qf4 44. g5 c2 45. g6 b1=Q 46. g7 h1=Q 47. d8=Q Qhg2 48. g8=Q h3 49. Qfg7 h2 50. Qge8 h1=Q 51. f8=Q c1=Q+


Trapped by this strange opening line, how to proceed?

I have never seen this idea before, but it is not as stupid as it looks.

There are basically three options for white:

Play the Veresov, i.e. 4.f3. In that case black will argue that he has the black side of a Caro-Kann-Fantasy variation and that he will at one point play c5 in one move, regaining the tempo lost with d6-d5.
Play exd5. In that case black will say that he has a Scandinavian defense and that compared to the line 1.e4 d5 2.ed Nf6 3.Nf3 Nxd5 there is no 4.c4 kicking the knight from d5 and establishing a nice space advantage.
Play e5. In that case black will probably play 4...Ne4 and you can try to be tricky with 5.Nce2, trying to catch the knight with f3. Taking the knight directly with 5.Nxe4 is also possible, but there is probably no way to quickly assault the weak pawn on e4.

I think 4.e5 is the most principled option, but it is no refutation. You'll get a very complicated fight were the most you can hope for is that your opponent has to be more careful than you.


I'm not certain what you exactly mean with it is considered next to the Sicilian. However, first of all, I would like to state that the Sicilian Defense is not always aggressive. It depends on the line you play. Often, if White castles Queenside, the game becomes very sharp. However, if White castles Kingside, the game often becomes less sharp.

The biggest problem with the French Defence is the development of Black's White Squared Bishop. The French has either very sharp lines and less sharp lines, such as 1. e4 e6 2. d4 d5 3. exd5 exd5, known as the Exchange Variation.

But in general, both openings can be really aggressive. You could take a look at:

For the Sicilian Defense:

Sicilian Defense, Dragon Variation, Yugoslav Attack

Sicilian Defense, Dragadorf Variation

Sicilian Defense, Najdorf Variation, English Attack

And for the French Defense:

French Defense, Winawer, Poisoned Pawn Variation.
French Defense, King's Indian Attack.

Again, I'm not sure what answer you're looking for, but I believe that these (aggressive) lines may be very helpful comparing them. Seeing games (especially of higher-rated players, such as GMs, makes the opening-ideas a lot more clear, so I suggest doing that.


What is the disadvantage of the move 3. ..h6 in the Queen's Gambit Declined?

I suspect that a good try for white here is to go into Colle-Zukertort system: http://en.wikipedia.org/wiki/Colle_System#Colle.E2.80.93Zukertort_System

Then 3...h6 is not only a tempo loss, but also a unpleasant weakness of the king side.


What is the difference between an inaccuracy, a mistake and a blunder on lichess?

Blunder: 300 centipawns

Mistake: 100 centipawns

Inaccuracy: 50 centipawns

This is sourced from http://en.lichess.org/qa/75/how-are-these-determined-blunder-mistake-and-inaccuracy

It is the first thing that appears when you google "lichess inaccuracy mistake blunder".


What are some good books on the Caro-Kann which propose a Black repertoire based on positional, strategic, solid, boring and quiet variations?

I would suggest The Caro-Kann: Move by Move. The author, Cyrus Lakdawala, is very lucid & seems to play in the style that appeals to you. Specifically:

He advocates same side castling in the classical variation
He gives an alternative to the ...c5 break in th advance variations, namely the ...f6 break
He advocates ...e6 in the Panov

The move by move series goes through top level games with question and answer format. Many of the games covered were played by Karpov, so if you like his style of play, then you'll like the book. Smyslov, the endgame virtuoso, has a significant number of games too, seeing as the first few chapters cover the Smyslov variation of the classical lines.

PS. I have no affiliation with the author - I'm recommending the book because I'm a Caro-Kann player who likes the book.


https://decodechess.com/ advertises this kind of service but I doubt if it's really useful.


What are some good podcasts to listen to?

The Full English Breakfast by Stephen Gordon, Laurence Trent and Macauley Peterson was always fun. It has been discontinued 2 years ago but it might still be worth a look.


How many 2200+ FIDE rated players are there?

According to FIDE, there are 20,763 players rated 2200 or above (as of May 2021). 9,460 are currently active


My bishop is attacked by a rook-pawn, now what?

Usually the bishop doesn't end up by chance on this square, so why did you move it there in the first place? I can think of three reasons:

pin the knight in order demobilize it (e.g. an indirect attack on a pawn)
pin the knight in order to take it (e.g. to give the opponent a doubled pawn)
provoke a weakness in the opponent's pawn structure

Be clear which of these motives apply in your case before you move, then you know what to do afterwards. Obviously "development" isn't a motive, but just an excuse here.

By the way, if your bishop is on b5 and the bishop on c8 isn't developed, sometimes Qa4 is an option (axb5 Qxa8).


Queen's Indian Defense question that has me stumped

The simple reason is because 3...b6 doesn't prevent 4.e4! when White immediately grabs the center.

   [FEN ""]

   1. d4 Nf6 2. c4 e6 3. Nc3 b6 4.e4!

The bishop on b7 isn't very effective in the kind of pawn structure that arises after e4. Often, White may play f3, strengthening the e4 point and completely blunting the bishop on b7.

Consider this structure -

   [FEN "4k3/pbpp1ppp/1p2pn2/8/2PPP3/2N2P2/PP4PP/4KB2 w - - 0 1"]
   [Event "Bishop on b7 is blunted by White's pawns on e4 and f3"]

Black may want to break White's center with a move like d5, but that allows White to play e5, driving away the knight on f6 with tempo and also establishing a strong pawn on e5, which may enhance White's attacking prospects on the kingside, as I discussed in point number 4 of this post.

  [FEN "4k3/pbpp1ppp/1p2pn2/8/2PPP3/2N2P2/PP4PP/4KB2 b - - 0 1"]
  [Event "The threat of e5 is always looming after d5"]

  1... d5 2. cxd5 exd5 3. e5

Black may also want to play c5, but in those positions, after a move like d5, the position transposes into Benoni type positions where the bishop is completely misplaced on b7, thus Black loses at least a tempo. Besieds, b6 might also be a waste of time in some Benoni positions.

   [FEN "4k3/pb3ppp/1p1pp3/2pP4/2P1P3/2N2P2/PP4PP/4K3 b - - 0 2"]
   [Event "Unfavorable transposition to a Benoni type position"]

Recommended Games -

The following games in this line are quite instructive -

Harry Nelson Pillsbury vs Heinrich Wolf, 1902 1-0

   [White "Harry Pillsbury"]
   [Black "Heinrich Wolf"]
   [Date "1902"]
   [Result "1-0"]
   [FEN ""]

   1. d4 Nf6 2. c4 e6 3. Nc3 b6 4. e4 Bb7 5. Bd3 d5 6. cxd5 exd5 7. e5 Ne4 8. Nf3 Be7
   9.  O-O O-O 10. Qc2 Nc3 11. Bh7 Kh8 12. bxc3 g6 13. Bg6 fxg6 14. Qg6 Qe8 15. Qh6 Kg8
   16. Ng5 Bg5 17. Qg5 Kf7 18. f4 Ke6 19. f5 Kd7 20. Qg7 Kc8 21. e6 Rg8 22. Qh7 Rh8
   23. Qg6 Ba6 24. Qe8 Re8 25. Re1 Nc6 26. Bg5 Nd8 27. Bd8 Kd8 28. f6 Rh8 29. Re5 c6
   30. Rae1 Rc8 31. Rg5 Bd3 32. Ree5 Rh6 33. Rg8 Kc7 34. Rc8 Kc8 35. e7 Bg6 36. e8=Q 1-0

Efim Geller vs Mark Usachyi, 1957 1-0

   [Event "UKR-ch"]
   [Date "1957"]
   [White "Geller, Efim P"]
   [Black "Usachyi, Mark"]
   [Result "1-0"]
   [FEN ""]

   1. c4 Nf6 2. Nc3 e6 3. d4 b6 4. e4 Bb4 5. Bd3 Bb7 6. f3 O-O 7. Nge2 d5 8. cxd5
   exd5 9. e5 Ne8 10. O-O c5 11. a3 Ba5 12. b4 cxb4 13. Na2 Nc6 14. Rb1 bxa3 15.
   Bxa3 Ne7 16. Ng3 g6 17. Nc1 Bc6 18. Qe2 Ng7 19. f4 Re8 20. f5 Nexf5 21. Bxf5
   gxf5 22. Nb3 Qg5 23. Rf3 Rac8 24. Rbf1 Ba4 25. Nxf5 Rc3 26. Nxg7 Qxg7 27. Nxa5
   Rc2 28. Qxc2 Bxc2 29. Nc6 Qh6 30. Rg3+ Bg6 31. Ne7+ Kh8 32. e6 Rxe7 33. Bxe7
   fxe6 34. Rc3 Be8 35. Rc8 Qe3+ 36. Kh1 Qe2 37. Rxe8+ Kg7 38. Ref8 h5 39. Bd6 h4
   40. Be5+ Kg6 41. h3 a5 42. Rg8+ Kh5 43. Rf7 1-0

Phillip Viner vs Elias Castrillon, 1964 1-0

   [Event "Tel Aviv ol (Men) fin-D"]
   [Site "Tel Aviv"]
   [Date "1964"]
   [Round "5"]
   [White "Viner, Phillip"]
   [Black "Iniguez Castrillon, Elias"]
   [Result "1-0"]
   [FEN ""]

   1. d4 Nf6 2. c4 e6 3. Nc3 b6 4. e4 c5 5. d5 d6 6. Bd3 Nbd7 7. f4 exd5 8. cxd5
   Be7 9. Nf3 O-O 10. O-O a6 11. a4 Bb7 12. Bc4 Qc7 13. Re1 h6 14. e5 Nh7 15. b3
   Rfe8 16. Bb2 Ndf8 17. Qd2 Ng6 18. Rad1 Bf8 19. Ne4 Qd8 20. Nxd6 Bxd6 21. exd6
   Qxd6 22. f5 Nf4 23. Be5 Rxe5 24. Rxe5 g5 25. fxg6 Nxg6 26. Qxh6 Nf6 1-0


How can I set up en passant in the Popeye engine?

The github page lists several help files in various languages: English, French and German. These are text files which can be downloaded. English is clearly not Thomas Maeder's mother tongue, I'm guessing German. Perhaps the German help file is clearer than the English.

As far as I can tell from the English file there is a long list of options you can pass to the program to define the problem you want it to solve. For en passant it defines the "EnPassant" option as follows:

  EnPassant  - Must be followed by 3-4 squares which indicate the  pawn
  move just played:

  departure square
  avoided squares
  arrival square


Why aren't there any women super Grandmasters (GMs)?

I don't know a lot about chess or even gender differences in cognition, but I do know enough that chess involves certain aspects of cognition and that there are gender differences in cognitive ability. For your question, about the number of super GMs, the average abilities of men and women is more or less irrelevant. You need to look at the tails of abilities. Again, there are differences in the tails. Men are better (both on average and at the extremes) for some abilities and worse at others. Women tend to excel at verbal and social cognition while men excel at spatial aspects of cognition.

In addition to cognitive differences, men and women react differently to competition and my guess is you cannot be a super GM without a strong competitive side. There are also social and cultural differences between men and women. Even if there were equal numbers of recreational players, that doesn't mean there would be equal numbers of competitive players (or similar rates of individuals willing to dedicate their lives to chess).

The popularity of competitive chess may well stem from its emphasis on male dominated traits (i.e., spatial cognition) and its lack of emphasis on verbal and social cognition.

The source of these gender differences (i.e., nature/nurture or intrinsic/learned) does not really matter, as the end result is that there are differences. As to whether these differences can explain the lack of women super GMs, it is not clear. That said, given there are measurable differences in cognitive abilities, reaction to competition, and social and cultural influences, it seems wrong to conclude that the lack of women super GMS means that men are smarter than women or that there are more male geniuses.


Is it allowed to talk to your opponent in a tournament game?

In this case, is it allowed to warn your opponent of the potential
  danger of flagging?

Yes. The rule which limits talking to your opponent is the one which forbids annoying the opponent, article 11.5 -

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

If your opponent has left the board and you remind him of the time control this cannot be interpreted as distracting or annoying. It is helpful.


The new, munged* FIDE rating website still has the old "Advanced Search" option, but the page doesn't have its own URL. There you can search for GMs from all countries sorted by rating ascending and then you get that the Russian GM, Vasily B Malinin, born in 1956 is the lowest rated GM with a standard rating of 2100.
Looking at his individual calculations shows that his rating has been in steady decline since 2004 which would suggest some life-changing event happened then, perhaps a health problem, which affected his chess playing ability.
*mung = self referential acronym = Mung Until No Good


My intuition might be totally off because this is very different from real chess, but I don't see why you wouldn't still want to try to control the center with pawns as white. You can develop all your pieces quickly this way but black can make a couple pawn moves (say, e5 and d5 while you are bringing your rooks out) then develop his own minor pieces to defend them. I wouldn't go with this opening strategy.


You don't seem to know the kind of plans that arise out of the way you played the opening. You lined up the Be3/Qd2 "gun" and then never fired it! You needed to play Bh6 at an early stage and look at the possibility of h4,h5 and maybe even sacrifice the exchange if conditions are right if he plays Nxh5.

"Winning" is another question, but you never really made him struggle and fight. Your hand was never anywhere near his windpipe!

Ne2 isn't great. I know you are already a pawn down at this stage, but leave the knight there to protect the pawns and instead look at Ra2-h2 to build a rook battery on the h file. It's a much quicker attempt to get at his exposed king while he is still a bit disorganized.


Here's a link to the fide calendar: https://www.fide.com/calendar

Also, this link includes the tournaments which will feature some of the top super GMs (e.g., the Olympiad, Sinquefield Cup, Altibox Norway Chess): https://chess24.com/en/read/news/2020-chess-calendar


There is an issue with the syntax you are using. According to the UCI protocol you should use position startpos moves e2e4, i.e., the moves keyword is missing in your command.


The chess.com Chess Clock app has a big pause button right smack dab in the middle of the screen and pauses itself when someone calls. (Just tested it to verify)


No. Rule 9.1.2.1 of the FIDE rules says it all:

  9.1.2.1 A player wishing to offer a draw shall do so after having made a move on the chessboard and before pressing his clock. An offer
  at any other time during play is still valid but Article 11.5 must be
  considered. No conditions can be attached to the offer. In both cases
  the offer cannot be withdrawn and remains valid until the opponent
  accepts it, rejects it orally, rejects it by touching a piece with the
  intention of moving or capturing it, or the game is concluded in some
  other way.

(rule 11.5 is about not distracting the opponent during his move)

It's expected that the opponent takes his time to think about the offer, just as he probably spends time on thinking about his next move. He isn't required to actually refuse the offer, just making a move is quite normal too (once he touches a piece to move the offer is over, see above).


If the situation is as in the diagram below, it is stalemate. You correctly noticed that white has no legal moves: any potential move would put the white king into check, which is not allowed. Furthermore in the position the white king is not attacked, so it is stalemate (not mate).

       8/8/8/6rk/8/5qPK/7P/8 w - - 0 1


How do I learn to visualize algebraic notation?

I think that improving your analysis and visualization skills is very important. I posted a question on this topic recently as well (How can one improve their over-the-board analysis skills?).

But your question is more specific and I think you need to NOT try and study the Reassess Your Chess book in your head. The material he covers is too complex to be followed mentally for a class player. Also, because your visualization skills are not well developed you are going to waste far too much time and energy on firming up the image of the board and not be able to dedicate enough of your mental CPU to actually digesting the ideas in the book.

Notice that I use the Chess Success book in my visualization training. McDonald's book has diagrams every 5 to 8 moves and his analysis is very direct with shallow trees. It's really a great tool for doing visualization training. And even though I am fully able to follow the moves in this book and accurately draw the images I still go over each game with his analysis using a board after I do my training so that I am certain I have understood everything he has said.

You need to separate the idea of study and training. When you are studying a book like Silman's or Pachman's you need a physical chess board and a computer board as well to get the full benefit. Those types of books are for study. Use something simpler for visualization training.

Here is some advice from USCF Life Master A.J. Goldsby on how to study a chess book (from his Training Program page).

  Many people think studying a chess book can be done by reading and
  occasionally looking at the diagrams. Nothing could be further from
  the truth!

  The only correct way to study a chess book requires  AT LEAST  one
  chess set.  And a good little analysis set on the side. Maybe a
  magnetic set to boot.

  Basically, to really get any real instruction from ANY chess book, you
  must set up the position and play through the example. (More than
  once.) NEVER (!)  (Even if you can play blindfold chess like me!!);
  think you can follow a series of moves in your head. Set up your board
  and  play through  every example  and every single variation!

  When I study, I often set up a chess board on my table. I have a
  little peg set off to one side, that I keep the current position on.
  And I also usually utilize one magnetic set. I play over every single
  move, line and variation. Often I will question a line, and spend a
  lot of time analyzing lines the author may not have even looked at.
  (As a Master, I have an obligation to try to find as many mistakes in
  analysis as I can. And on top of all this, if it is a very complicated
  game, I more often than not will have the position set up on at least
  one chess computer, analyzing the game and the variations.)

Even though we live in a very digital age I think it is important to use a real board as well as to keep another board with the current position so that you can quickly go back to the original position and consider it at the same time as you are looking at another position for analysis on your main board.


Is CT-Art better for tactic training than chesstempo tactics?

The answer to the title question is "No, they're both excellent for tactics training and are good at different things."

Chess Tempo:

problems are a random selection of positions taken from actual games (chosen by computer to be good chess problems)
over 100,000 problems and growing
problems are served to you based on your rating
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Page 5 in the paper has your answer:

  ... AlphaZero compensates for the lower number of evaluations by using its deep neural network to costs much more selectively on the most promising variations - arguably a more "human-like" approach to chess ...

"selectively" is the key word. What does that mean? Let's use this following position for our example:

  https://chess24.com/en/read/news/london-classic-5-caruana-shows-how-it-s-done

This is a recent game won by Caruana in 2017 London Chess Classic. The White bishop is under attacked, and you know you have to move it. But where?

Possibilities (not losing a piece):

Bh4
Be3
Bd2
Bc1

What was Caruana thinking?

  I felt like I would lose at some point, but when I saw, 25.Bc1 I suddenly
  started to get a bit more optimistic about my chances. I realised my
  position is bad, but at least I had a plan and that was really all I needed
  for some confidence in this position. When I saw this b3, c4 the position is
  double edged and I have some chances.

This is human thinking, and a "human move". Caruana hadn't considered Bh4, Be3 and Bd2 because they "looked" bad. He had been focusing only and only on the Bc1 move.

Humans play chess very selectively, we discard unreasonable moves because we don't have time to examine all possibilities equally.

We discard Bh4 because it release the tension on the h6 pawn
We discard Be3 because it blocks the two white rooks on the third rank
We discard Bd2 because it blocks the White queen to the king side

That's what AlphaZero trying to claim in the paper. They claim their algorithm, although slower than Stockfish, is able to selectively pick better moves than Stockfish in the search. While Stockfish is faster, it wastes time on bad moves. AlphaZero is slower, but it's more precise (like what Caruana was doing).

For example, AlphaZero might spent 80% resources on Bc1, and 20% on all other bishop moves. Stockfish might give 25% for each move (Bh4, Be3, Bd2, Bc1).


Where can I find a large collection of random chess positions?

The easiest way I can think of is to write your own scraper (say) in Python.
I'd use beautifulsoup and aim at several sites, including Google Images (within whatever limits they impose)

If you are familiar with Python, this SO question is all you really need.

Start with Google Images, chessbase.com, and then make a round of the numerous chess websites that have tons of position images that you can scrape.


The Elo rating system is a rating system for two-person, zero-sum games based on the assumption that performance is normally distributed. That is, a player's performance is expected to follow a normal distribution. For FIDE the mean = the player's rating and standard deviation = 2000/7 = 285.7.

It was developed by Arpad Elo and first implemented by the USCF at a meeting in St Louis (where else?) in 1960. So, the USCF rating system is the original Elo rating system. It was later adopted by FIDE in 1970. Many other federations also implement Elo rating systems and it is also used in other sports, for instance soccer.

It has since been discovered that players' performances are not strictly normally distributed. Lower rated players have a better chance of an upset result against higher rated players than their ratings suggest and so the basic system has been tweaked by different federations (including FIDE) over the years. Varying k factors are one variable that is changed.

Elo rating systems predict relative performance, not absolute performance. Hence FIDE, USCF, Lichess, Chess24 ratings, although all elo rating systems, are not comparable. All you can say is that if player A has a higher rating in one implementation than player B then you expect that in a different implementation player A will again have a higher rating than player B although it is not certain. The likelihood will depend on the difference in ratings and the standard deviations of the systems.

So, the bottom line is that Elo rating is a system of rating and FIDE rating is a particular implementation of Elo rating.


How should white continue after 5...Qf6 in the Scotch Game?

First, I'd note that the most popular move after 4... Bc5 (according to the game databases of both Chess Tempo and Chess Games) is actually 5. Be3, and I suppose there's an argument to be made that it's both the more ambitious and the more principled move because it attempts to maintain control and/or occupation of the d4 square rather than immediately ceding it. In those main lines, Black is generally seeking to play a freeing ...d5 pawn break, when White's center is either liquidated or White is forced to push his pawn to e5 (typically supported by a pawn on f4), creating a structure where Black must blockade and aim to attack the head of the White f4-e5 chain while White seeks to bolster and ultimately advance it.

It's typical of most variations in the Scotch that Black gets a slight lead in development in exchange for White's superior pawn structure and has to use piece play (combined with timely pawn breaks like ...d5) to avoid the dreaded "Scotch ending" where White has a mobile king-side pawn majority while Black's queen-side pawns can be blockaded (due to the pawn doubling that normally takes place on the c-file in many lines).

In the line that you specifically refer to, the only two common and respectable continuations are either 6. Qd2 or 6. Qf3. (I have seen 6. Qe2 played, presumably with the idea of not blocking the dark-square bishop and intending on castling queen-side, but it's comparatively rare and, statistically, its practical success rate looks abysmal.) Of these, I've always preferred 6. Qf3, precisely because it doesn't impede White's development in the way that 6. Qd2 does by blocking the dark-square bishop.

In those variations, if Black does capture on f3 (which he almost always does relatively quickly, except in the lines with 6... Qxc6, which are the least common), White's pawn structure is not as compromised as it might superficially appear after the obligatory g-pawn recapture, and in fact gives White a solid central presence and open files and diagonals for his pieces. Those lines lead to relatively standard endgames where the dark-square bishops also normally get traded very quickly and White seems to do well. 6... Qxc6, which is rare, may be a good reply, where Black again aims for a ...d5 pawn break and extremely symmetrical positions arise in which piece play dominates and major strategic themes don't particularly present themselves with any force or consistency.

If none of this sounds appealing, the only other (semi-)respectable way to play the Scotch is as a gambit line with 4. Bc4, appropriately but boringly called the "Scotch Gambit." Notably, this was recommended in the book Chess Openings For White, Explained. Unfortunately, none of the major lines are particularly forcing, and if Black is reasonably familiar with classical open games, he can transpose into lines of either the Giuoco Piano or the Two Knights Defense where he returns the pawn and easily equalizes (in fact, I'd say Black has a more pleasant position in the best of the Two Knights Defense lines than White does).


What are the goals for white and black in the Caro Kann exchange variation?

From that position, both sides will finish development and most likely castle kingside. Then...

White's goals/plans:

Put pressure on the e-file in the interest of forming a kingside attack. This is often done by playing Rfe1 (or Rae1), followed by Ne5. White could then move the d2-knight to f3, bringing it closer to the kingside. After that White will try to continue building up the pressure around the kingside, perhaps even with a Rook lift (i.e., Re3).

Another possible plan of White's is to play c4, accepting an isolated d-pawn in order to open up the game. This plan isn't so common, but it could work if Black's unprepared in the centre.

Black's goals/plans:

Begin a minority attack on the queenside by playing ...Rb8, ...a6, ...b5, and eventually ...b4. By doing this, Black plans to exchange on c3, leaving White with a backwards pawn after White captures back.

Black may also play ...e5, which is the converse of the aforementioned plan for White of playing c4. Black rarely plays the ...e5 plan though, mainly because White just has too much control over that square.

Finally, an important defensive motif for Black often involves maneuvering his light-squared bishop to the g6 square. From here, it blocks the b1-h7 diagonal, neutralizing White's d3-bishop and safeguarding the Black king from attacks.


Photographic memory is closely related to board vision in Chess, where in you instinctively and instantly know something is wrong with the position ( yours or your opponent's) or it clicks to you that you've seen this or a similar position before.

Though memory capacity might seem like an "in-born" talent, I would argue it can be developed to some degree with practice. Play as many professional games as possible. By professional, I mean tournament games with real humans face-to-face. Tournament games build the seriousness that is necessary for forming long term memories. I've seen in my experience that when I am playing a lot of serious chess, I can easily detect board patterns and tricky positions than when I am out of touch with chess.

One more technique to improve board vision and memory is to try NOT to write down the moves while playing but replay the whole game from memory after the game. I've seen that over a period of time, you are better at remembering your own games. Even though you will not be able to remember every game you play, it will improve your memory in general.

Regarding the notations, start speaking in terms of them whenever you describe a game to a friend or whenever you self-analyze a game. It is tricky. Especially the 4th and 5th ranks. I always say Bg4 from White when its supposed to be Bg5 and vice versa.

Keep practising and I am sure you will get good at both board vision and notations.

EDIT
To answer your edited question,

  Finally, if you are born with a photographic memory, does that mean it
  will help you to WIN in chess?

Winning in chess has to do with many more things than just photographic memory. Tactics, Strategies, Staying calm under time pressure are just a few things that are vital to success but hardly have anything to do with memory. Having a good memory helps in chess but there are still a lot of other aspects to master to become a master!


Play chess in Python programming language?

Yes. You can use the package to play against yourself and an engine. While I don't think there is one function that can do everything for you, but I can give you hints:

To setup up a game against an AI:

Read UCI documentation (you can find on Google)
Read the UCI functions for python-chess here
Spawn an engine thread by engine = chess.uci.popen_engine("/usr/games/stockfish")
Start a new game by engine.uci()
Send a move by engine.position
Start analysis by engine.go
Get engine results by command.result()

You will need to read the documentation carefully.

To setup a game against yourself (copied from the package documentation)

>>> import chess

>>> board = chess.Board()

>>> board.push_san("e4")
Move.from_uci('e2e4')
>>> board.push_san("e5")
Move.from_uci('e7e5')
>>> board.push_san("Qh5")
Move.from_uci('d1h5')
>>> board.push_san("Nc6")
Move.from_uci('b8c6')
>>> board.push_san("Bc4")
Move.from_uci('f1c4')
>>> board.push_san("Nf6")
Move.from_uci('g8f6')
>>> board.push_san("Qxf7")
Move.from_uci('h5f7')


Are there any engines that present evaluations based on probability of finding moves?

No engine do what you describe because it’s too hard to code a imperfect human brain. Estimating positional complexity at humans level is also quite hard.