How do strong players react to being paired with a (much) weaker player in a tournament?

I think the best thing you can do when playing a player that is rated below you is forget about the ratings, and play the person across from you, not their rating.
The last thing you want to do is this:

Hmmm.... If i make this not very strong move, my weak opponent has an
opportunity to make this blunder (and I am sure that they will), and I
get to win a game right away with a pretty tactic, and if he or she
plays properly I'll outplay him or her later anyway because I am
stronger. So I will go for it.

The above is a recipe for disaster. I know from experience.
Also, I don't think that 200 point gap is very big. I believe that the weaker player is expected to score 25% (one win in four games or two draws in four games).


How to play a Grandmaster in a simultaneous?

I've answered a very similar question here

My take is that GM try to avoid calculating, and try to rely on their superior positional understanding. So striving for a tactical position, seems like a good bet. Your game seems to support this hypothesis.

Here is interesting story, that involved somebody I used to know over the internet and Kasparov:

  [Kasparov] rather nervously asked me if I had a rating. I replied 2084 and he, not looking very happy, asked why I didn't write it down in front of the board next to my name. I replied that no one asked me too and that the Belzberg people knew my rating and only today OK my playing since I am a client. He then stated that if he had known I was rated that highly he would have played differently rather than getting into a very theoretical line. Being aware of the 2000 cutoff I again appologized for the misunderstanding and we quickly realized that the Belzberg staff had erred in not telling people to write down their ratings (these were different people than from the NYC event). I simply stated "I'm sorry for the confusion, I won't play" and started to get up and Garry, reiterating that he'd have played differently vs a rated expert, started resetting the pieces to the starting position and said we can restart. Being rather shocked by this and what was over a minute of commotion and confusion I knew the gentlemanly thing for me to do was to step away and let someone else under 2000 play.

source

The position was a very sharp double-edged Scandinavian. Something even Kasparov wouldn't want to play against a high-rated player.


Is there a space between the move number and the move algebraic notation?

As you already noted, both are used. Either style is acceptable, and engines, pgn viewers etc. will usually not have any problems with either of them. The most common is probably without the spaces though, especially with long series of moves it can be argued it improves the readability a bit by not having unnecessary extra spaces. In books the notation will probably always be without spaces if for no other reason than to conserve page space over the length of the book.


How can I make my child interested in playing chess?

In my experience it is likely that kids get interested in whatever you are interested in.  So, play a couple of chess games with a friend or set up some chess problems and work on them yourself at a time where your kid can see what you are doing.  It is quite likely that your kid will start asking questions what you are doing and wants to play as well.

Whenever my sons sees me setting up the chess board he wants to play... unfortunately he is not even three years old, so besides learning the names of the pieces there is not much he can do yet. ;)


Difficulty of attaining USCF rating in different states.

Ratings are not exactly "given", but determined from the outcome of games.

If 1) there is enough mixing (players from Indiana play against those from California, etc) and 2) if many games are played, the ratings should be comparable between states.

Conversely if a group of players is separated because they only play among themselves, this can lead to distortion of their ratings compared to players outside their group.


Is it really possible to checkmate with two knights and king against a
  king?

Theoretically, the checkmate is possible, but you can not do it in practice unless the weaker side allows you to. This is related to a drawback in the way knight moves.

  There is a mating position with this but no extra tempo to do it in
  real game.

  What are the explanations, why knights cannot create an extra tempo
  around 64 squares on the board?

There are two reasons:

They can not do it because they can not move to another square while keeping the previous one in control ( like bishop and many other pieces can ) and because they need too much time to position themselves properly.

DEMONSTRATING KNIGHT'S INABILITY TO "LOSE TEMPO" :

Take the following position as an example:

[Title "This position is won with a bishop"]
[fen "8/8/8/8/4B3/8/P7/K1k5 w - - 0 1"]

This position is won for White because he can play with bishop and retain control over c2 square ( 1.Bh7for example ), which will create zugzwang. As you say in your question, White will "lose tempo" and force Black to move his king away.

Now analyze this position with a knight instead of a bishop:

[Title "If it is White to move this is a draw"]
[fen "8/8/8/8/3N4/8/P7/K1k5 w - - 0 1"]

Why is this endgame only a draw? Because White can not move and keep control over c2 square. This means that he can not create zugzwang, or as you say he can not "lose tempo" to force Black king away.

Without the ability to create zugzwang you are just not able to corner the opposing king.

DEMONSTRATING KNIGHT'S INABILITY TO POSITION ITSELF PROPERLY :

As for the positioning problem, we shall take a look at the below diagrams:

[Title "Agile and swift bishop"]
[fen "8/8/8/8/8/1K1N4/3B4/1k6 w - - 0 1"]

1.Nb4 Ka1 2.Nc2+ Kb1 3.Na3+ Ka1 4.Bc3#

Here, bishop needed 1 move to reach the mating square. Notice that the endgame would be drawn, just as the one with two knights, if bishop was not able to reach c3 in one move.

In the following diagram you will see that knight needs more moves to reach the mating square, which enables the weaker side to draw:

[Title "Clumsy knight"]
[fen "8/8/8/8/8/1K1N4/4N3/1k6 w - - 0 1"]

1.Nb4  Ka1 2.Nc2+ Kb1 3.Na3+ Ka1

and here Ne2 needs 2 moves to reach c2 and deliver checkmate.

Remember this: Knights experience great difficulties when they need to reposition themselves between short distant squares in a short notice. This is often impossible task for them. The following example demonstrates clearly what I mean:

[Title "Slow knight"]
[fen "8/8/8/8/8/1K5p/6N1/1k6 w - - 0 1"]

In this position we can see how hard it is for the knight to position himself fast to a square nearby like f3 or g4. Again he needs 2 moves to do this and thus he fails to save the game.

SUMMARY:

Knight's way of moving gives him ability to "do the impossible". He can "jump over" obstacles, his attacks can not be stopped, his line of fire can not be covered or intercepted, but all these beautiful features come with a price. He is slow and clumsy when he needs to reposition himself to a square in its proximity, and if player can not "buy" him enough time to do that then knight fails to accomplish this task.

Hopefully this post answers your question. If you have further questions leave a comment.

Best regards.


Chess tactics software which can read files

The format of the file is described here. According to this, the name of the columns are: PuzzleId, FEN, Moves, Rating, RatingDeviation, Popularity, NbPlays, Themes, GameUrl.
I do not know of any software to deal directly with this type of file. But (I see you're a software engineer) it's not difficult to write a snippet to convert the csv file (mainly columns FEN and Moves) to a pgn file that could be opened with any chess database manager.


Why increment isn't popular online blitz?

The main reason, I think, for online blitz sessions not including increment/delay is the possibility of premoving. You can't premove in OTB chess, so you will use the increment for the 'motion' time.

Personally, I feel 3+0, where you have to keep good track of your clock, is more challenging than 3+2, where you just have to liquidate to a winning endgame using your time more freely and then play on the increment until checkmate. In sudden death games, you can flag your opponent if you are losing, so once they get a winning position it is not game over :)


Good tournaments in 2017 to go for a sport holiday

I can recommend you the Faaker See Open in Austria,Carinthia.

http://www.faakerseeopen.at/faakersee_open.php#english

It is an lovely area close to a nice lake and mountains nearby.
I have played two times there myself and it is good organized, but if you go there don't book the bed and breakfast place called Pension Wrolich.(It might look cheap but it is not worth it)


Why do some players never accept a draw offer?

I'm going to assume here you're playing against people you don't know very well in a park somewhere.

While you both know it's a draw, he's assuming that you don't know how to play it out or that you'll lose your patience and make a blunder. After you both have played against each other some time, you'll both know what you can and can't win against each other and he will offer draws out of his own initiative. Unless, of course, your opponent is very stubborn then you just have to put up with it.


1. d4 Nf6 2. c4 c5 3. f3  The first two moves signify an A56 Benoni but 3. f3 does not show up in my database as a typical continuation.

1. d4 Nf6 2. c4 g6 3. f3 is a playable E60 King's Indian.  3. ... Bg7 is a good followup for Black.

1. d4 Nf6 2. c4 e6 3. f3  The first two moves signify an E00 Queen's pawn game and are very drawish.  3. f3 is not a typical continuation.  3. e3 gives White more chances for the point.

1. d4 Nf6 2. c4 d5 3. f3 The first two moves of this are also an A50 Queen's pawn game.  Again, 3. f3 is not commonly played.

I suspect 3. f3 isn't popular for good reason and would recommend you try another continuation.

EDIT - so, why is f3 bad?  In the first continuation, Stockfish believes it drops a 'pawns worth' of value:

[fen ""]
1. d4 Nf6 2. c4 c5 3. f3 cxd4 4.Qxd4 Nc6 5.Qd2 e6 6.Nc3 d5 7.e3 Bc5 8.a3 a6 9.b4 Ba7 10.c5 O-O 11.Nge2 e5 12.Bb2 Be6 13.Rd1 Re8 14.Na4 Rc8 15.Qc2 h6

We see that by after his 7th move, Black is having a splendid game.  After the moves above, Black controls the center and is doing fine.  White hasn't even castled yet.  The problem with f3, ultimately, is that it doesn't do anything to constrain Black.  It takes a good square from the Knight which will eventually deploy to the passive e2.  Further, f3 looks silly if it isn't followed by e4 sometime soon.  White only manages the passive e3. I don't like how f3 opens the e1-h4 diagonal and nor do I like how it allows a Queen or Bishop on the a7-g2 diagonal to look at the King which will likely be sitting on g1 in most variations.


What is considered a decisive evaluation of a board in chess?

You need to realise that any number given as answer (including the 1.5) is just a rough estimate which depends on many factors. Professional players were  mentioned because their play will be close to that of computers so that blunders/mistakes do not affect the statement. An evaluation around 1-1.5 in the midgame often means that the player can make use of his advantage further improving the evaluation. On the other hand in an endgame with few pieces on the board a similar evaluation can be a lot more drawish because there are few options to improve.

And there are many other reasons why you can't really give absolute numbers.

If you want to discuss the situation for amateur players it gets really vague as you need to make assumptions about the blunder rate. Perhaps the following is useful....

When analyzing a game in lichess, the engine knows three levels of error: blunder, mistake, inaccuracy corresponding to a change in evaluation of 3, 1, 0.5 respectively. So for instance if you start from an advantage of 5, you can make a blunder and still have a won position.


What's the most offensive opening for Black?

This is an incredibly general question, because obviously white is allowed to make some moves as well … there is no one fits all aggressive defence.
But to give an equally general answer: If you like to play aggressively playing gambits makes a lot of sense. So everything with "gambit" in its name is a valid choice.

I'll give a few examples and will assume that you didn't specify whites opening because all your opponents play 1.e4. ;-)

This would be the Latvian Gambit against the Italian Game:
http://en.wikipedia.org/wiki/Latvian_Gambit

rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1

1.e4 e5 2.Nf3 f5

This is the Schliemann-Jaenisch-Gambit against the Ruy Lopez:

rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1

1.e4 e5 2.Nf3 Nc6 3.Bb5 f5

Generally the idea of these gambits is to speed up the development of your pieces at the cost of a pawn and to gain greater central control by diverting your opponents central pawns.
If you play well, central control and active pieces will lead to an attack.
If you play badly, you're just down a pawn ...


What's wrong with Long castle in accelerated Dragon being white?

In the normal Dragon, the most dangerous system is the Yugoslav attack.  Current theory shows that Black can resist the attack with a pawn sacrifice and maintain the balance.  In the Accelerated Dragon, Black saves a move by moving the d pawn to d5 in one move.  This allows Black to gain a dangerous initiative.  With a Rook on the c file and the Bishops on g7 and f5, White must defend carefully.


How would you play this position as White?

The elements which I notice are The strong knight on d5, the attacks on c1 and f4, the backward pawn on c7, and that white is down a pawn.
Since I can't do anything about the Nxf4 threat, which would ruin the pawn structure and create a weakness on d4, but also eliminates the powerful knight, my first candidate move would be Ra1 to try and regain the pawn due to the pin.  I'd have to consider the reply Nac3 followed by b4, which would sheild the c7 weakness, save the pawn, and the knight may prove to be strong on d3.
The second candidate is Rc5, Rc6 is bad due to Bb7, just to keep pressure on c7.  After Nxf4 and rerouting the other knight to d5, black just has a better game.
The third option is to sacrifice the rook and save the bishop by Bg3.  Being down 3 pawns worth of material and black protecting all of his weaknesses, white has no compensation.
With all considerations, I would choose Ra1 and, if black entrenches on c3, to go for an all out attack on the kingside while black's pieces are distracted on the queenside.  Due to white's lack of development and black's solid kingside, there is little chance of saving the game, but I believe that this is the best attempt.


Why did GM Kogan play such a bad opening in this 1997 game?

haha well, I was in inspired mode and played one of the MOST creative games of my career that brought me many compliments from genius creative GM as Benko (that watched the game LIVE) and few others too :-)  Not everybody can appreciate 'creative chess' or rather concrete chess with concrete ideas that created big problems and search for HARMONY (for a pawn gambit!)disturbing opponent's normal DVP, while fighting for big center etc and Josh was also shocked and even after the game didn't really appreciated what happened.. (he was 'too conservative' as a player and I could already feel he will never become a GM...) in one point I was with big edge close to winning, but did the old sin to enjoy the position too much and made a blunder... Greetings from Spain! Arthur www.olalachess.com


How about this website: http://database.chessbase.com/js/apps/database/

It's pretty good.


Are there any resources where one can view the popularity of a move by year?

SCID's Opening Report shows some statistics which may be useful here. From a given position, one of the things it does is generate a table which shows what moves are common from a given position:
4.2 Moves from the report position
    Move   ECO       Frequency    Score  AvElo Perf AvYear %Draws
 1: Nf3    E10a     8561: 50.8%   56.1%  2622  2665  2009   56%
 2: Nc3    E00d     6495: 38.5%   55.6%  2607  2654  2008   54%

The "AvYear" column there shows the average year in which the move was played.
And another table looks like this:
1.4 Current popularity

Year               1800-99 1900-49 1950-69 1970-79 1980-89 1990-99 2000-09
Once every X games   ---     24      19      13       6      33      12

Frequency in all years:   once every 12 games
In the 10 years to today: once every 13 games (down 7% from all years)
In the  5 years to today: once every 12 games (no change from all years)
In the  1 year  to today: once every 0 games (no change from all years)

which seems like it would be useful.


Duplicating the game analysis output on lichess

If you know a little python or shell programming you could try and use uci for each move and grab stockfish output, I will try and see if I can get this sorted at some point and share the code.

If just being offline is your concern, then try the stockfish app, there is offline analysis.

Again, from a programming angle, there is trying to add such a feature to scid.


Struggling to improve past intermediate level

Unfortunately playing against computers is a mistake amateur players often make.

There is not much to learn from computers as they are just that, computers. You will lose the psychological aspect which dominates a significant part of human chess. Computer's "plans" are based on brute calculation and not a  "feeling" for the position, as human players do. You cannot calculate to the level of a computer, nobody can, but you can obtain a "feel" for the position, and this can only be learnt by playing with strong human players.

That is the key, to play against strong human players, be it on the internet or in real life, preferably in real life. I myself never played against computers, and instead concentrated on playing on internet chess websites. But the greatest aspect of my improvement was my experienced gained from playing strong human players, in real over-the-board games. This helped me to absorb their ideas, their plans and to become an overall better player.

Keep solving tactical puzzles, your doing good, don't stop! Tactics is a crucial part of chess and can help in transforming advantages from one form to another and to decide the game in your favor. Tactical Awareness can also stop you from making blunders and seeing your opponents threats before he executes them...

 "My opening and end game skills I think are adequate for the level I am playing at"

The endgame is a crucially important part of chess which amateurs always disregard. I cannot stress enough the importance of it. The legend himself Capablanca stressed the importance of the endgame. Improvement in the endgame will guarantee improvement of your entire game. Do not just neglect study of it because your endgame skills are "adequate for the level" you are playing at (1400-1500). Move forward. You neglect study of the endgame, and you wonder why you are not improving, well...

For openings its not as serious at your level. You just have to know the basic principles (control the center, develop pieces, castle quickly). Restrict your opening choice as well to make study of it easier. For example, don't play all 1.e4 1.d4 1.Nf3. Don't respond to 1.e4 with all 1...c5 1...e6 1...c6. Play just one opening! This will make it easier to absorb the ideas of that opening and will leave you more time to improve other aspects of your game.

Jeremy Silman's Complete Endgame Course is the perfect book for the improvement of the endgame at your level. I recommend reading up and practicing until the 2000 level. Do not be intimidated by the rating, it's just a number. Some of the material is challenging but I'm sure with repeated practice you will absorb it easily.

OK I know I'm a Jeremy Silman fanatic but How to Reassess Your Chess is truly a great book which helped me to improve. Not trying to sell anything here, but it really is fantastic material.

To answer your question about creating positions that arise from puzzles

"is this a common pitfall in players around my level"

Well this just shows that you are at that level. Common pitfalls of players at your level is missing tactical combinations, implementing the wrong plan (bad judgement of the position) and ignorance of the endgame.

Relating to your previous question

"how do players usually break through this?"

Break through the common pitfalls of players at your level?

Perfect question to finalize my post, as I mentioned before.

1.Play against strong(er) players (preferably in real life)

2.Study the endgame

3.Continue practicing tactics!

4.Read How to Reassess Your Chess Or take a look at this

OK just going to recommend a bunch of websites to help you

Chess Tempo

The Chess Website

Chess

Internet Chess Club

Chess Network

Chessgames


The pattern starting from Nxf7 does not correspond to any known (opening) trap. It's to be expected as this does not really qualify as a trap for the following reasons:

The path up to the critical position 10.Nxf7 has major flaws, e.g. white is hanging a full knight on move 7.Ng5 (7...Qxg5), so objectively, white is already lost before any trap setup is reached. Therefore, this move order does not really belong to a branch of a known opening (here the Four Knights game: Italian var).
Opening traps usually occur when one side is baited/tempted towards a known losing variation, such as the Légal Trap. Sometimes the side attempting to set up a trap might have to make a non-optimal, nearly dubious move to force the desired variation, but (at least for most known traps) if the opponent spots the trap and plays a refutation the game remains about equal.

However, in your example, assuming black is indeed setting up a trap, white can [*] simply play 11.d4 instead of falling for 11.Nxd8, and white's completely winning as both dxc5 and Bxh6 are threatened and they cannot be simultaneously parried, therefore, black is lost and if anything, all this has been nothing but a last attempted tactical bait in an otherwise completely lost position.

[*]: other than the fact that white can simply play 9.Kd1 instead of Kf1 and be completely winning having also side-stepped black's combination along the f-file.


What is the solution to this mate in 2 puzzle?


What are the best repertoire books for White with the English Opening?

In the Grandmaster Repertoire series, there are three books covering the English opening from white's perspective, written by GM Marin in 2009 and 2010: Volume 1, Volume 2 and Volume 3.

More recently, in 2016, IM Cummings wrote a repertoire book based on e3 systems, rather than fianchettoing the bishop with g3.

Update: In 2018, a new repertoire series from white's point of view is published: The Modern English, written by GM Georgiev and IM Semkov. In Volume 1, the authors discuss 1.c4 e5.


From a full board to a pawn endgame in the shortest possible number of half-moves

Such a game more than likely doesn't. The game that you give is amazing enough in that 16 already exists. Without access to a database, however, I don't know for sure. Perhaps someone could try to do that, and search in one or two. But again, more than likely it doesn’t exist due to the extreme conditions and setup that a real game would have to arrive at the do it, not to mention that there are two minds involved.
Just for fun, as a related note that isn't an answer, here is the fastest possible game with such a sequence.
[Title "me, chess.stackexchange.com 7/3/2020, Non-Unique Proof Game in 15.0 Moves"]
[FEN ""]

1. e3 e6 2. Qf3 Qf6 3. Qxb7 Qxb2 4. Be2 Be7 5. Nf3 Nf6 6. O-O O-O 7. h3 h6 8. Kh2 Kh7 9. Qxa8 Qxa1 10. Qxb8 Qxb1 11. Qxc8 Qxc1 12. Qxf8 Qxf1 13. Qxe7 Qxe2 14. Qxf6 Qxf3 15. gxf3 gxf6


Is it possible to force checkmate with King, Knight, and Bishop vs. King?

Yes, mate can be forced in 33 moves from nearly any position, according to Wikipedia.

See the standard "w" maneuver cited in that article.


Challenge: Create the longest set of moves where the game is able to be perfectly reproduced from only the current board state and move number

The current length record is an astounding 57.5 moves (115 half-moves).
[Title "Dmitri W. Pronkin & Andriy Frolkin, Die Schwalbe 06/1989, 1st Prize, PG in 57.5"]
[FEN ""]

1. a4 h5 2. a5 h4 3. a6 h3 4. axb7 hxg2 5. h4 d5 6. h5 d4 7. h6 d3 8. h7 dxc2 9. d4 a5 10. Bh6 c1=R 11. e4 Rc5 12. Ne2 Rh5 13. e5 c5 14. e6 Nc6 15. b8=R a4 16. Rb4 a3 17. Ra4 c4 18. b4 c3 19. b5 c2 20. b6 c1=R 21. b7 Rc4 22. b8=R Qa5+ 23. Rbb4 Bb7 24. Nbc3 O-O-O 25. exf7 e5 26. Rc1 Bc5 27. f8=R a2 28. Rf3 a1=R 29. Na2 g1=R 30. Rfa3 Rg6 31. f4 Re6 32. f5 g5 33. f6 g4 34. f7 g3 35. f8=R g2 36. Rf5 g1=R 37. Bf8 Rg7 38. Ng3 e4 39. Bd3 e3 40. O-O e2 41. Rcc3 e1=R 42. Bc2 R1e3 43. d5 Rdd7 44. d6 Rdf7 45. d7+ Kb8 46. Qd6+ Ka8 47. Qc7 Nge7 48. d8=R+ Nc8 49. Rdd3 Rhg8 50. h8=R Rae1 51. Rh6 R1e2 52. R1f2 Rce4 53. Kf1 Bd4 54. Rfc5 Ne5 55. Nf5 Nc4 56. Nd6 Nb2 57. Rbc4 Nb6 58. Qb8+

This length record was reportedly beaten in 2017 by Pronkin, Frolkin and Keym (to 58.5 moves) but unfortunately it turned that the longer problem had more than one solution. I do not know if the authors managed to make the problem sound.
Although this problem is not computer-checked, it has withstood human testing for 41 years, so it might as well be considered computer checked by the greatest computer of them all-the human mind.


Timeline of key historical changes to FIDE Laws & WFCC Codex?

Is there a timeline of "key" historical changes to rules (FIDE, USCF
and earlier)

Not so far although former FIDE rules commission member, Stewart Reuben, recently said:

To make it clear. I am writing a book, together with my co-authors Alex McFarlane and Sean Press. It is called A History of the Laws of Chess. Alex is dealing with the first section, from about 600 AD to the 15th century with the old rules. Sean is dealing with the introduction of the augmented powers of the queen, bishop and pawn 15th century to the formation of FIDE. I am dealing with the Laws since FIDE was formed IN 1924. That section is more-or-less completed.


Why does the computer want to undermine this pawn chain at the tip instead of at its root?

You would like an answer that does not "go into deep variations", but if all such questions could be answered just on general principles, chess would not be as interesting as it is. In this particular case 5.c5 is definitely premature and BOTH methods of undermining the center work well, transferring the initiative (but no more) to Black. The tactics are important. AS Glorfindel observes, after 6..a5 the chain cannot be preserved. If it could, the assessment would change. Usually, though, you either need to strike soon, or you must be able to see that a delayed strike cannot be prevented.

But computer assessments at early stages of the game do not mean much. Stockfish is just saying that both approaches are playable, and you cannot trust it more than that.


What if White declines the Volga Gambit?

The position you've shown looks at first glance to be a poor side-line of the Benko (Volga) gambit for white, both the timing of h3 and Nc3 seem out of place. For instance let's reach that position (somewhat sensibly) by the following line: (annotated)

 [title "A path to OP's Benko gambit sideline"]
 [fen ""]
 1.d4 Nf6 2.c4 c5 3.d5 b5 4.Nf3 g6 5.Bf4 Bg7 6.h3 {h3 is well unnecessary here, in Benko the c8 bishop doesn't target the g4 square anyway, and if the f6 knight wants to re-route to e5 it doesn't have to go via g4, but d7. Thus, h3 is a waste of a tempo when white is already behind in development} (6.Nbd2 O-O 7.e4 {is much more to the point if you don't want to accept the gambit}) (6.e3 {yet another possibility, Nbd2 Be2 O-O are in queue unless black does something active} d6 {black cannot allow d6}) d6 7.Nc3 O-O 8.e3 {this is your suggestion: it doesn't really work here as you c3 knight is misplaced if you don't want to accept the gambit, now b4 comes with a tempo and your knight will end up either on the rim or hindering your own pieces} (8.Nxb5 {seems to be the most sensible choice, not damaging your pawn structure and not offering black to play a6 getting rid of its weak pawn and activating the bishop via a6-f1 diagonal.} Ne4 9.Nd2 {Not giving black chance to take on b2} Qa5 {pinning the knight and preventing Nc3 and preparing to take on b2 again} 10.Qc2 {sure visually it doesn't look great for white, but we're holding for the moment.}) (8.cxb5 a6 {accepts the gambit again but allows for the usual follow-up with a6-bxa6-Qb6 etc}) b4 {when the knight is on d2, b4 is less dangerous because you'll still be able to challenge it with a3 in time} 9.Ne2 Ne4 {g7 bishop alone is dominating the position, white lacks in development and dark square control, without any real other compensation to speak of} 10.Nd2 Nxd2 11.Qxd2 a5 {I think at this point black's advantage is quite clear.}

To conclude the above analysis in short key takeaways:

This is generally not a desirable Benko line for white. 6.h3 seems well out of place, white should be pushing to complete development (so that you can quickly start challenging black's queen-side or creating play in the center, none of which is possible with your king still on e1.)
7.Nc3 is not the way to go if you don't want to accept the gambit, you're allowing b4 without any repercussions for black, and your knight will be mis-placed. 7.Nbd2 is a much better try. If you want to stick to 7.Nc3 then it's best to start considering accepting the gambit, either 8.Nxb5 or 8.cxb5 each with their own merit and far more playable than 8.e3.
After 8.e3 b4 white is objectively behind: the knights seem out of coordination, the bishop on f4 is staring at a wall, there are no clear pawn breaks for white, the queen-side is permanently weak and there are no quick ways of creating counter-play on the king-side as we're far behind in any attempt to challenge the g7 bishop (Qd2-Bf4 battery is not possible with e3, nor is there any re-routing for the bishop to return to d4-g7 diagonal). This also answers your main question: Black should not respond by Nbd7 after 8.e3, instead 8...b4 is the main move to consider, exploiting the mis-placed c3 knight while increasing your grip on the dark squares, leaving no real ways for white to challenge the g7 bishop (note b4 is also stopping any future attempts at Bd2-Bc3)
Small recommendation (for the white side): avoid the Bf4 side-lines, none of them are really interesting for white, in fact in many of the Benko variations the bishop belongs to its original c1 square for a long time as b2 is continuously under pressure. Instead consider the 5.Qc2 variation if you don't want to accept the gambit, which can roughly go as follows: 5.Qc2 Bg7 6.e4 d6 7.Be2 O-O 8.O-O. I think after going through some of the possible side-lines of this variation, you can convince yourself that this is a much more sound continuation for white. Alternatively, accepting the gambit is known to yield the best play for white, namely lines such as 5.cxb5 a6 6.bxa6 Bxa6 7.Nc3 (black does have a different kind of compensation now, but by accepting the gambit we've prevented b4 altogether and revived chances to challenge the dark-squares) 7...Bg7 and many ways for white to continue.

Welcome to ask additional questions, either regarding the analysis or more related to the black side of the Benko gambit.


Unless I misunderstand your question wouldn't that just be  (for every from square) the number of (to) squares that a knight can go to plus the number of squares that the queen can go to. As in the following diagrams which show to how many squares the respective piece can go.

You'd just need to add the two numbers from the diagrams for every square.

Depending on what you need all this for you might have to consider separately the special moves of castling, en passant and pawn promotion.


If you make a checkmating move before your flag falls, but then your flag falls before you press the clock, you win. The relevant FIDE rules (emphasis mine) are:

5.1.a. The game is won by the player who has checkmated his opponent’s king. This immediately ends the game, provided that the move producing the checkmate position was in accordance with Article 3 and Articles 4.2 – 4.7.
6.2.a. During the game each player, having made his move on the chessboard, shall stop his own clock and start his opponent’s clock (that is to say, he shall press his clock). This “completes” the move. A move is also completed if the move ends the game (see Articles 5.1.a, 5.2.a, 5.2.b, 5.2.c, 9.6a, 9.6b and 9.7).
6.3.a. When using a chessclock, each player must complete a minimum number of moves or all moves in an allotted period of time.
6.9 Except where one of Articles 5.1.a, 5.1.b, 5.2.a, 5.2.b, 5.2.c applies, if a player does not complete the prescribed number of moves in the allotted time, the game is lost by that player.


Principally I like your idea. I really like it. I could even imagine to implement something like that just for fun sake. However, there are some problems:

At a certain stage, an average player with a strength of about 1400 will just end up copying his engines moves in an extremely tactical position, which he doesn't understand.
If there is an ELO difference between the engines of only about 50 points (what's pretty common, especially in the higher levels), one could easily win by luck (since a higher ELO doesn't necessarily mean a 100% win chance) or even by just playing as white. This issue however can be fixed by giving opponents with about 200 ELO more, so one's not going to win by his engine itself.
Humans usually rather play with other humans, since they're more predictable. An average machine sees almost every trap in one or two plies, while humans may overlook it. "Playing for tricks" is essential, especially in quicker time controls.
One might struggle to proceed further at a certain level. It's unterstandable, that it becomes boring to play (and lose) to the same engine over and over again.

Sorry for my bad english, I'd appreciate any suggestion. (:


Is the Queen plus pawn versus Queen endgame always a draw?

My question concerns the Queen+pawn versus Queen endgame. Assuming that the pawn is on its initial square (second rank for white, seventh rank for black), are all these endgames objectively drawn? Second of all, what is the best strategy for the player with the material advantage to aim for a win?

Emphasis above are mine, and since you have 2 questions I shall answer both separately.

  are all these endgames objectively drawn?

No they are absolutely not!

  Second of all, what is the best strategy for the player with the material advantage to aim for a win?

Without seeing the exact position I can not answer that-your question is too broad-these endgames require thorough study as everything counts there ( the position of the kings, who moves first and so on ).

I can recommend you Yuri Averbakh-Comprehensive Chess Endings ( Volume 3 ) to learn how to win Q+P+K vs K+Q endgames. There you have described patterns for winning with the bishop/knight/rook/central pawn, queen and king vs king and queen.

I have just suggested the above book because it is written for all levels of play-from novice up to grandmaster-so with that knowledge you can not squander your edge, but if you find something else even better for you!

The key is just to learn how to recognize winning position and to learn how to win it.

All you have to do now, is to use this tablebase to see how can you reach the winning position.

If you have trouble finding exact winning moves you can always go through tablebase moves-just click on the notation.

SUMMARY:

Learn how to win Q+P+K vs K+Q endgames->input the position you are interested in into tablebase->if winnable, play through moves to see how to reach winning position.

I know that this might be too broad of an answer to you, but you ask for help in Queen endgames and these are the toughest to master. Just one imprecise move ( not to mention wrong one ) gives your opponent a draw and squanders your edge!

Hopefully this answer helped you a little.

If you have further question leave a comment and I will reply.

Best regards.


This is just an issue every engine has (although they may miss different moves). In this case, it just pruned (ie, didn't consider/didnt consider enough) Ne6. It's not common per se, but has to be kept in mind
Also note Lc0 is not NNUE, it is just a normal neural network not NNUE which is special.


Why is Apronus allowing the White king to castle through an attacked square?

I happen to be the author of the chessboard editor under discussion. Let me clarify the issue.

This editor is supposed to enforce legal moves but it has a bug which prevents it from being able to make a pawn capture onto the final rank. Therefore it cannot notice that a black chessman controls the f1 square. If you place a black bishop on the a6-f1 diagonal then it won't allow White to castle.

There is a newer chessboard editor that is free from this bug: https://www.apronus.com/chess/puzzle/editor.php?editpuzzle=0, which is meant as a powerful puzzle editor but it can serve as a PGN editor, too.

The "position setup" interface can be used to illustrate an arbitrary sequence of chessboards, not necessarily legal or illegal moves. If you tick the checkbox "Animation sequence" you will see that it keeps a record of all board positions like frames in a movie. It allows you to delete certain frames which effectively allows you to set up an arbitrary sequence of board position and generate an animated GIF diagram. I am the author of this tool.


In the Caro-Kann Panov-Botvinnik Attack which move tends to lead to the most solid, positional, slow, closed, and quiet positions: 5... e6, Nc6 or g6?

Let me quote very strong GM ( taken from Lars Schandorff-Grandmaster Repertoire 7 The Caro-Kann ) :

  The famous Panov variation has always attracted aggressive players with White, and it is easy to understand why. With an active pawn move, White immediately creates tension in the centre and shows that he values the initiative more highly than mere positional matters, such as pawn structure. The Panov often leads to double-edged positions where White has isolated queen's pawn in exchange for fluid piece-play and general activity.

Please note the The Panov often leads to double-edged positions... part. I told you this before, and sadly here is the same case : White chooses here whether the struggle will be sharp tactical encounter or quiet strategical "debate".

That being said, let us examine all 3 moves and let us start from 5...g6 :

This is not entirely correct, but may be playable. Black struggles to draw by regaining the sacrificed d-pawn. So far White has pleasant advantage in the main lines, but maybe somebody will invent some novelty that will make Black's play fully equal ( I still have my doubts but who knows... ).

As for 5...Nc6 :

This move gives White lots of options to sharpen the game. He can go into Endgame variation where he has small initiative and better piece placement, or he can go into sharp lines with 6.Bg5. Here lines are very sharp. You can transpose to more solid lines with 6...e6 which may be what you want but be warned that Schandorff still believes White is slightly better there. Playing similar positions as Black, I must agree with him -> these are very tough to play as Black, at least they were for me. He prefers 6...dxc4 instead.

As for 5...e6, it might be exactly what you look for, but you really need latest theory here. Schandorff says that in the moment of him writing the book ( 2010 ) the Nimzo-Indian plan Karpov invented that starts with 5...e6 lost its appeal. Still, if I were you, I would look thoroughly for these positions as they were solid before. I doubt White can improve the game, so all you will probably need are good opening moves and you will be ready to go! 90% of the time you should be battling against Isolated Queen's pawn which is easier to play as Black... Just "do your homework" first!

I wish I was able to offer you some sample lines with 5...e6 but I have no up-to-date books on that :(

Good luck!


What is the best way to solve chess puzzles?

I had hit a plateau like you. Probably spent about two years at the same tactical rating level until I watched a video on chess.com (it's a series, actually, by IM dpruess "Exercises to Become A Tactical Genius") that reshaped my thinking entirely.

What I used to do was analyze each of my pieces, one by one, and explore the possibilities of each piece. It was almost a guess-and-check type methodology. Often I'd get the puzzle correct, but I took so long at doing it that my tactical rating would only go up only one point. In a game, doing this, I'd surely lose on time before arriving at the correct combination.

The video I'm referring to got me thinking in terms of concepts first and only then explore those moves that would play to the concept that stuck out the most in the position.

My recommendation to you is to first familiarize yourself with a complete list of tactical concepts. Then, when you are looking at your next tactical position, see if you can spot the concept or concepts that might be featured in the position so that you can look for ways to exploit that feature. For instance, if you notice a piece is pinned, see if any moves jump out at you that will make good use of that fact. In my experience, this technique will save you a lot of time because you'll find yourself only analyzing a small subset of possible moves and the odds that the right moves are in that subset will be high.

As a word of caution, be prepared to see your tactical rating take a big dip while you get used to this new way of thinking, but I believe that once you get the hang of this way of thinking, you'll see your tactical rating shoot up. For instance, I found my rating plateau at 1900 for a couple of years, changed to this way of thinking and saw it drop to maybe 1800 and then shoot up to 2300. All the best to you. I hope this helps.


Removing engine thinking (variations) in Arena Chess

Go to Options → Appearance → Movelist and under View uncheck "Show comments in the movelist". This should hide the engine thinking variations.
Alternatively, you can right-click in a move → Display → Comments.


Could this kind of inaccurate sacrifice be countered?

When asking questions about tactics and sacrifices, chess engines are usually the most efficient and accurate way of determining the answer. The following is based on analysis from Houdini 6.03 in tactical mode:

By the end of move 24, in the following position, a forced mate (in 8) already exists for white

[FEN "2rq3r/1R6/p3kp1Q/4p3/2p1P1PP/P1N5/2P5/4KR2 w - - 5 25"]

1.Rxf6+ { #8/58 } 1...Qxf6 2.Rb6+ Rc6 3.Rxc6+ Kd7 4.Qxf6 Rh6 5.Qxh6 Ke7
6.Rc7+ Kd8 7.Qd6+ Ke8 8.Qe7#

And Rxf6+ was indeed the optimal move. Later on, Rb6+ was completely fine, but not optimal (see analysis above). As it turns out, you lose your mate in 7 and are tragically left with the following mate in 19:

[FEN "2r4r/4R3/p3kq1Q/4p3/2p1P1PP/P1N5/2P5/4K3 b - - 1 26"]

1...Kxe7 { #19/50 } 2.Nd5+ Kd7 3.Qxf6 Rhf8 4.Qe7+ Kc6 5.Nb4+ Kb5 6.Qxe5+ Kb6 7.Qd6+ Kb7 8.Qxa6+ Kc7 9.Qc6+ Kb8 10.Qb6+ Ka8 11.Nc6 Rxc6 12.Qxc6+ Kb8 13.Qd6+ Kc8 14.Qxf8+ Kd7 15.e5 Ke6 16.Qd6+ Kf7 17.Qf6+ Kg8 18.h5 Kh7 19.h6 Kg8 20.Qg7#

It turns out the best move for black (the one which holds off mate for longest) is in fact to take your rook and allow themselves to be forked.

On move 27, the played move Kf7 allows the mate in 3. The best option, Kd7 is shown in the mating line above. It delays mate much longer than 3 moves, but obviously still loses.


What type of hardware is the most important for analysing with Houdini?

You have not read enough of Houdini's online user manual. First look at the 2.1 Installing Houdini page.

Specifically, it says you'll get 30% faster performance with 64-bit over 32-bit. It says it's optimized to use up to 6 cores. And Intel i5 will run it faster than an equivalent speed AMD Opteron. Their home page says it will use up to 4 GB of RAM for hash memory. Obviously from that, you'll want to get the highest clocked Intel i7 you can find with a 4th generation CPU.

But if you get Houdini 3 Pro instead of Houdini 3 Standard, it supports up to 32 cores and 256 GB of hash memory and NUMA-architecture (whatever that is). Their example performance comparison shows on a 16-core dual AMD Opteron-6128 box that Pro has a 20% speed gain over Standard. With the Pro version, you'll want as many cores as you can get, because that's the number of threads you'll be able to run at once. Intel i7 will likely be better than AMD for the Pro version as well.

Definitely read everything in the online Houdini 3 User's Manual, especially section 3 about its configuration. That tells you how to optimize it.


How much do you actually learn from the book Modern Chess Openings by Nick de Firmian?

The best uses for out of date opening books are -

Doorstop
Decoration
Emergency toilet paper supply when Covid means the supermarket has sold out

how far in terms of opening knowledge and building my opening
repertoire will memorising every line of the book get me?

You will be an expert in historical opening lines, but you will understand nothing.
MCO, latest edition 2008 as far as I know, is mostly composed of chess lines with minimal notation. Each line usually finishes with an evaluation like "=", "+=", "-+", etc.
I have the 11th edition from somewhere round about 1970. The last time I looked up a line in it was sometime in the 1970's. The main reason I still have it is that it is where I keep my signed scoresheet of my 1972 draw with Victor Kortchnoi - in a simul, obviously.
According to Amazon:

Best Sellers Rank: 874,393 in Books


What is the idea behind Schuhler Gambit?

Trades off time and space for a side pawn that loses more time for black if they try to keep it.
c6 was not a good response for black on move 1
in the position shown master results show an 80% win rate (draws =1/2)
for white with zero losses
black would do far better with 1 ...   d5 e5 or nf6


Is there chess software to play against that rates your skill through actual games?

I realize what I'm about to suggest isn't exactly what you have in mind, but still, it is technically software, and it rates your skill through actual games: play games online against other people, e.g. at FICS, Playchess, ICC or chess.com.

Instead of using some software that would have you play games against an engine (perhaps with various "levels" that are supposed to reflect various Elo levels), and then has some algorithm or other that tries to convert your results against it into your own estimated real-world rating, my suggestion cuts out the middleman and throws you right into a real-world pool. This way seems more efficient if nothing else (and probably more fun).

Now any rating you get at one of the sites I mentioned will be on a somewhat different scale than that for, say, actual FIDE ratings, and they will differ from site to site as well. But you will usually have some way to translate your rating there into a percentile (within that site's playing pool), and that would give you better information about your playing strength than any purely algorithmic guess about it will.


As we come out of lockdown, how much FIDE rated chess was played in June 2020?

I downloaded the latest July 2020 rating list and loaded the data into my database and ran a few queries.
First one to show the number of players who played standard, rapid or blitz per federation sorted by standard players descending. I also included the number of active players in the federation to give an idea of which federations were more active. I excluded federations where the number of players playing was less than 4 on the grounds that they were likely living and playing in other federations. That still gave an impressive list of 33 federations which look as if they are back playing chess.
Code    ActivePlayers   Standard    Rapid   Blitz
CZE 10838   2543    17  16
SVK 6704    1357    54  0
SWE 5331    449 1   0
CRO 7654    351 14  54
GRE 20595   338 0   0
DEN 5496    134 0   0
SRB 7436    112 75  69
ISR 4104    96  0   1
NOR 5165    93  0   0
POL 21407   85  38  40
HUN 7928    80  6   1
LAT 2758    69  86  99
MNE 822 69  0   0
SUI 3170    66  6   1
BUL 3038    60  1   0
ISL 1842    36  54  60
FIN 1308    36  0   0
LTU 3813    32  59  22
SLO 4320    31  44  82
NCA 712 23  0   39
GER 22613   22  1   2
EST 1517    22  0   6
BEL 5602    14  0   1
RUS 68077   8   3   1
ITA 18332   6   10  1
AUT 5640    4   2   0
UKR 11853   4   2   22
FRA 55783   4   1   2
TUR 36523   4   0   0
ESP 45444   4   0   1
IRQ 1515    2   47  0
THA 1082    0   14  0
KGZ 2688    0   10  0
What stands out as quite remarkable in that list is that over 20% of Czech and Slovak active players played last month!
Next a query to show the sum of standard players, rapid players and blitz players.
That gave for June 2020:
Standard = 6171
Rapid = 551
Blitz = 524
By comparison for June 2019:
Standard = 35708
Rapid = 18712
Blitz = 10569
Two things stand out

More than 60% of standard chess played in June 2020 was played in the Czech and Slovak republics
Standard accounted for far more of the chess played in June 2020 than in June 2019.

Next a query to show the sum of standard+rapid+blitz games per federation. Here is the top 20. Click on the federation link to see the list of tournaments reported for that federation in June 2020:
Code    Total   Standard    Rapid   Blitz
CZE    16002   7899    100 204
SVK    4848    2424    132 0
LAT    2625    599 672 1427
SRB    2097    435 560 1227
CRO    2074    719 80  636
GRE    1834    917 0   0
SLO    1663    138 300 1387
POL    1221    441 401 339
HUN   1213    601 8   11
SWE   1108    554 7   0
ISL   869 93  330 683
NOR   776 388 0   0
DEN   754 377 0   0
LTU   714 230 404 254
BUL   708 354 9   0
MNE   606 303 0   0
NCA   575 167 0   241
SUI   503 246 36  11
EST   354 144 0   66
ISR   319 155 0   9
The sum of games for June 2020:
Standard = 17562
Rapid = 3774
Blitz = 6844
For comparison the same figures for June 2019:
Standard = 247057
Rapid = 148693
Blitz = 121143
Digging deeper into the data for the Czech republic, you can see the tournaments reported for
June 2020 for the Czech Republic here and for
June 2019 for the Czech Republic here
43 Czech tournaments reported in June 2020 against 21 in June 2019. It looks very much like in June they aimed to catch up with all the matches and tournaments they missed during the lockdown.


Are the board positions of the 4 players of each country determined by Elo rating in chess olympiads?

Look for fixed board order in the FIDE handbook's Regulations for the Chess Olympiad. The essence is that the board order cannot be changed between rounds for the purpose of getting a strategic advantage.


Which chess position requires the most moves to reach?

This was published about in the latest entry of Tim Krabbé's Chess Diary. Harry Goldsteen has put some research into this and came up with a position which is reachable only in 185 moves:

[FEN ""]
[StartPly "371"]

1.a4 g5 2.Ra3 g4 3.h3 g3 4.Rh2 gxh2 5.Nf3 h1=R 6.d3 d5 7.Kd2 e5 8.Nh2 a5 9.Ke3 d4+ 10.Kf3 e4+ 11.Kg3 e3 12.Qd2 exd2 13.Rb3 d1=B 14.Bf4 b5 15.Nd2 bxa4 16.Rb7 Be6 17.Ne4 Ba2 18.Nd6+ Kd7 19.Nc8 Kc6 20.Nb6 Kb5 21.Be5 Bb1 22.Bf4 a3 23.Be5 a2 24.Bf4 a1=B 25.Be5 { As in the 183- and 184-move games, White makes many waiting moves. Black ´leads´, as Goldsteen puts it - he must play optimally, although some changes in move-order are possible for him, too. } 25...Kb4 26.b3 Kc3 27.Nd5+ Kd2 28.Nb6 a4 29.Nc8 a3 30.Nb6 a2 31.Nc8 Bb2 32.Nb6 a1=B 33. Nc8 Bc1 34.Nb6 Bc3 35.Nc8 Bcb4 36.Nb6 c5 37.Na4 c4 38.Nb2 c3 39.Kf3 cxb2 40.c3 Bdc2 41.Ke4 Ne7 42.Bc7 Nd5 43.Be5 Ne3 44.Bc7 Nd1 45.e3 h5 46.Be2 Qh4+ 47.Kd5 Na6 48.Bg4 hxg4 49.Kc4 g3 50.Rb5 gxh2 51.Rb7 Re1 52.Rb5 h1=R 53.Rb7 Nc5 54.Bh2 Ne4 55.Rb5 Ng3 56.Rb7 Rhf1 57.Rb5 Nh1 58.g3 { Now White has created the smallest possible box in which Black´s promoted Rooks and Bishops manoeuver like tar through a sieve. } 58...Ke2 59.Rb7 Kf3 { The black King makes room for the white Rook so it can go to g2. In the next phase, the black Rooks must leave the box, otherwise the white Rook cannot pass. } 60.Rb5 Bfc5 61.Rb7 Re2 62.Rb5 Ba2 63.Rb7 Bcb1 64.Rb5 Rc2 65.Rb7 Re1 66.Rb5 Ree2 67.Rb7 Bd2 68.Rb5 Be1 69.Rb7 Rc1 70.Rb5 Bc2 71.Rb7 Ra1 72.Rb5 Bcb1 73. Rb7 Rc2 74.Rb5 Rc1 75.Rb7 Bc2 76.Rb5 Bab1 77.Rb7 R1a7 78.Rb5 Ba2 79.Kd5 Ra1 80.Kc4 Bab1 81.Kd5 R1a6 { Now the white Rook can enter via a5. } 82.Ra5 f5 83.Ra1 Ba2 84.Rc1 Bcb1 85.Rc2 Qh5 { Or Qg4; the Queen must be able to reach e2 in one move. } 86.Re2 Bd2 87.Re1 Bc2 88.Rg1 Bab1 89.Rg2 { The Rook has arrived. } 89...Ra1 90.Kc4 Ba2 91.Kb5 Rc1 92.Kc4 Bab1 93.Kb5 Ra1 94.Kc4 Ba2 95.Kb5 Be1 96.Kc4 Bcb1 97.Kb5 Rc2 98.Kc4 Re2 99.Kb5 Bc2 100.Kc4 Rc1 101.Kb5 Bab1 102.Kc4 Ra1 103.Kb5 Rha8 104.Kc6 Bd2 105.Kb5 Re1 106.Kc4 Rg1 107.Kb5 Ba2 108.Kc4 Bcb1 109.Kb5 Rc2 110.Kc4 Bc1 111.Kb5 Re2 112.Kc4 Ree1 113.Kb5 Ref1 114.Kc4 Bc2 115.Kb5 Bd2 116.Kc4 Rc1 117.Kb5 Bab1 118. Kc4 Ra1 119.Kb5 Ba2 120.Kc4 Be1 121.Kb5 Bcb1 122.Kc4 Rc2 123.Kb5 Ke2 { The black King must enter the box now; his first goal is a3. } 124.Kc4 Kd2 125.Kb5 Kc1 126.Kc4 Re2 127.Kb5 Kd2 128.Kc4 Bc2 129.Kb5 Rc1 130.Kc4 Bcb1 131.Kb5 Rc2 132.Kc4 f4 133.Kb5 Kc1 134.Kc4 Rcd2 135.Kb5 Bc2 136.Kc4 Kb1 137.Kb5 Ka1 138.Kc4 Bab1 139.Kb5 Ka2 140.Kc4 Ka3 141.Kb5 Ba2 142.Kc4 Bcb1 143.Kb5 Rc2 144.Kc4 Rc1 145.Kb5 Bc2 146.Kc4 Ra1 147.Kb5 Bcb1 148.Kc4 Rc2 149.Kb5 { Only now can the black Queen treacle into the box. } 149...Qe2 150.Kc6 Qd2 151.Kd5 Qc1 152.Kc6 Re2 153.Kd7 Qd2 154.Kc6 Bc2 155.Kb5 Rc1 156.Kc6 Bcb1 157.Kd7 Rc2 158.Kc6 Qc1 159.Kd7 Rcd2 160.Kc6 Bc2 161.Kd7 Qa1 162.Kc6 Bcb1 163.Kb5 Rc2 164.Kc6 Bd2 165.Kd7 Bc1 166.Kc6 Ree1 167.Kd7 Rce2 168.Kc6 Bd2 169.Kd7 Bc2 170.Kc6 Qc1 171.Kd7 Bab1 172.Kc6 Ka2 173.Kd7 Ka1 174.Kc6 Ba2 175.Kd7 Bcb1 176.Ke8 Qc2 177.Kd7 Bc1 178.Ke8 Rd2 179.Kd7 Ree2 180.Ke8 Rfe1 181.Kd7 Rgf1 182.Bg1 f3 183.Rh2 Ba3 184.Ke8 Bcb4 185.Kd8 Ba5+ { and the diagram has been reached. }

This is the current record, but

  Goldsteen does not have proof that 185 is unsurpassable - in fact, he thinks it is likely that it can be surpassed.


Can pieces follow different paths from one square to another in a single move?

For queens, bishops and rooks moving from square A to square B there is only one way that move can be made and all the squares in between must be empty for that move to be legal.
For a knight moving from square A to square there are generally two ways but that is irrelevant because knights can jump over pieces in the way.
For castling there is only one way the king can move from A to B and the intervening square must be empty for that move to be legal and the king must be moved first. For castling there is only one way the rook can move from A to B and all the squares in between must be empty apart from the king for that move to be legal.


How to counter 3. Nf3 f5 in the King's Gambit Declined

3...f5 is not a very good move, but it's not a terrible one; there's no immediate refutation. White's best response (verified with the chess program Houdini) is probably to deal with the pressure on his e-pawn by playing 4.exf5 Bxf5 (4.d3 would be passive; 4.Nc3 fxe4 5.Nxe4 d5 gives Black a nice center), then continue to develop, say with 5.Nc3 (covering e4 so that fxe5 is a real threat; if 5.fxe5 dxe5 6.Nxe5 now then 6...Qh4+ 7.g3 Qe4+ double-attacking the knight and rook). White's position is more pleasant but Black is certainly not lost.


Confused about timing of cxd5 and dxc4 in the Queen's Gambit Declined (QGD)

In the various standard variations of QGD, the answers to this question are somewhat different, but you should keep in mind Black's main goals.  Black's main problem is that they don't have enough good places for all of their bishops and knights.  The worst piece is the light-square bishop, but the other minor pieces are also problematic.  Hence Black's main goal in the latter stages of the opening are first to exchange off some minor pieces and second to free up the light-square bishop in some way.

Let me start with the Tartakower (1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Be7 5. Nf3 h6 6. Bh4 0-0 7. e3 b6)  In this variation, Black tries to put the light-square bishop on the long diagonal.  Naturally, black wants to play dxc4 so that the d5 pawn isn't blocking their own bishop.  White doesn't want to allow this, so the standard continuation is 8. cxd5 Nxd5 9. Bxe7 Qxe7 10. Nxd5 exd5.  The light-square bishop is now free, and Black has managed to exchange one pair of bishops and one pair of knights, but white has managed to prevent Black from putting their bishop on a dangerous open b7-g2 diagonal.  (This argument also applies to the Capablanca variation of the Orthodox.)

Next consider the main line of the Orthodox (1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Be7 5. Nf3 0-0 6. e3 Nbd7 7. Rc1 c6 8. Bd3 dxc4 9. Bxc4 Nd5)  In this variation, Black is achieving the exchange of a pair of bishops and a pair of knights by moving their knight to d5.  They need to move their pawn out of the way in order to achieve this.  However, they delay taking this pawn until White has moved their bishop.  The point is that this bishop now has to move a second time to retake the pawn, wasting one move.  White delays moving the bishop as long as possible, and Black delays taking the pawn as long as possible, but it turns out White runs out of other useful moves before Black does.

In the Lasker (1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Be7 5. Nf3 h6 6. Bh4 0-0 7. e3 Ne4 8. Bxe7 Qxe7), one plan for white is to retake on c3 with the b pawn and exchange off the pawn on c4.  This in effect exchanges the b pawn for the e pawn and gives White more pawns in the center, at the cost of giving Black pieces more space.  There are some variations with 9. Rc1 that see the pawns stay around for a while.  On the other hand, if White plays Bd3, Black can take the pawn and force White to move their bishop a second time.


Examples of recent early opening novelties at the top level

Aronian vs Anand at Candidates 2014 (http://www.chessgames.com/perl/chessgame?gid=1751406) was out of theory after Black's 3rd move, but only because White played an extremely odd opening which will probably never be repeated at the top level.

Aronian vs Leko at Morelia-Linares 2008 (http://www.chessgames.com/perl/chessgame?gid=1486033) featured a strong novelty on White's 9th move.


What ambiguities remain in the laws of chess?

This is purely academical, but there is an ambiguity whether the position after 1.Nf3 Nf6 2.Ng1 Ng8 is the same as the position at the beginning of the game.

Indeed, article 9.2.2 of the laws of chess states that:

  Positions are considered the same if and only if the same player has the move, pieces of the same kind and colour occupy the same squares and the possible moves of all the pieces of both players are the same.

Indeed, the second and third requirements are met. The problem is with the first one. After 1.Nf3 Nf6 2.Ng1 Ng8 there is no doubt that white "has the move" since her opponent's move has just been made, and law 1.3 defines "having the move" as:

  A player is said to ‘have the move’ when his opponent’s move has been ‘made’.

But who "has the move" in the starting position ? If we follow textually the rules of chess and the definition above, noone "has the move" in the starting position, since noone's opponent's move has been made.

Law 1.2 just says:

  The player with the light-coloured pieces (White) makes the first move

This confirms that the possibilities after 1.Nf3 Nf6 2.Ng1 Ng8 are exactly the same as in the starting position, but doesn't define "having the move" in the starting position. So, can we say that the two positions are identical in respect to article 9.2.2 ?

Well, that's where the ambiguity lies.

Obviously, this problem can only be relevant if someone claims for a threefold repetition when reaching a position 'identical' to the starting position. Which shouldn't happen too often. And such a claim might be denied anyway for lack of affrontment. So I suppose this should not prevent us to play chess with a free mind.


Is it possible to improve by playing mostly blitz?

Blitz is good for working out the kinks in an opening repertoire and reinforcing themes that you already know, but it won't help if you want to learn new tactics or ideas.

Blitz is too fast to be conducive to figuring out new plans, especially 3 0.

There are some upsides to blitz, though.  First and foremost, blitz is fun!  If you have 20 minutes, a few blitz games are probably going to be more enjoyable than digging up an old master game and slogging through that.  If you go over blitz games afterwards, you'll definitely learn more about your openings as well.

In terms of reinforcing themes and working on tactics, if you make an honest effort during the game to look for the best move and work out the complications (as opposed to just making speculative sacrifices), then yes, it can be useful.

So to summarize, nothing quite compares to going over games between two grandmasters, but blitz isn't terrible.  Make sure that when you do end up playing slow games you settle down and think long enough on every move.


When should you trade off a piece that's defended by two pawns?

Then only strategically relevant reason, that could reasonably be attached to the concept you presented, is in my opionion, that the subsequent change of the pawn structure is unfavourable for the defender. Reasons would vary wildly with the concrete pawn structure. E.g.:

In the maroczy structure white may play Nd5 after preparation and if
black captures the knight, white can capture with the e-pawn and make
the e7 pawn backwards. Or white captures with the c-pawn, opening the
c-file because he suddenly can invade over it.

In the stonewall structure black plays often Ne4 and if white would
take, black would normally recapture with the f-pawn, having a half open
f-file and driving a knight on f3 away. This may lead to an attack or
if not that could force white to take prophylactic measures with f3,
leading possibly to simplifications. Hence white often avoids the
exchange altogether and prepares to kick the knight with f3 and a
further e4.

If white has an isolani on d4, he often play Ne5 or even Nc5. If the
knight is taken on c5, this leads to a passer. If the knight is taken
on e5, white strenghten his pawns and again may become attacking
chances.

Your questions makes absolutely sense to me, but if you want to study chess seriously you can only answer it in on a case by case basis. Stockfish is your friend.
Old FM Roese at your service (https://lichess.org/@/fiskaren)


Yes the characterization is correct, and there are 58,084,310 legal collections in total.
To make headway, we need the right level of discourse, avoiding loss of accuracy while avoiding diving into trivialities.
Necessity & sufficiency of the deletion moves
Two kinds of operation were suggested to be necessary & sufficient to reach all legal collections:
(1) Delete a (non-K) officer & promote at most 1 wP and 1bP
(2) Delete a P & promote at most 1P of that color and at most 2Ps of the other color.

Firstly, the two criteria are necessary. To unblock a file a capture must take place. Capturing an officer will allow both pawns from a file to promote. A pawn capturing a pawn from a neighbouring file is more efficient, as it allows three pawns to promote.
The condition is also sufficient, as can be seen by dividing up the board into 4 pairs of files. We have to make assumptions that the kings can keep out of the way of the action. See later for an example which explores the validity of this assumption.
"Supply & demand"
Maybe worth moving on to the question of which collections are achievable in this way:

Count the number of visible "non-starting officers" for each side (queens beyond the first; other officers beyond the second of that type): N_w & N_b
Count the number of "awol pawns" on each side: (pawns morphed into NSOs aren't counted): A_w & A_b
Count the number of "missing officers" for each sides (missing queen, or other officers less than the second of that type): M_w & M_b

Then the following elegant "supply & demand" inequalities are necessary and sufficient criteria for a legal collection:
M_b + 2*A_b >= N_w - M_w - A_w
M_w + 2*A_w >= N_b - M_b - A_b

Grouping the terms by White & Black, the left hand side is the "supply", the right hand side is the "demand". The supply is always non-negative, so if the demand is zero or less, it's always satisfied. Similarly, a supply of 8+ will meet any demand that can occur.
Here's an example. Can we have 18 queens on the board? Yes!
N_w = N_b = 8
(because 8 promoted pawns on each side)

A_w = A_b = 0
(every missing pawn was promoted)

M_w = M_b = 6
(all Rs, Bs & Ns were captured)

M_b + 2*A_b >= N_w - M_w - A_w
translates to:
6 + 2*0 >= 8 - 6 - 0
6 >= 2

So this is legal. Similarly for White supply for Black demand. Even if we had the knights still on the board, so M_b = M_w = 4, the inequality would be 4 >= 4, so still legal.
Aside on mate/stalemate
Some wonder if such a position can be achieved without mate or stalemate, which is a fair question. The answer is yes. It's like asking to prove that 450g of cornflakes will all fit in a box. It's a matter of common experience that one can just shake the pack and the cornflakes settle down. There are not too many cornflakes in the box. Although it's obviously illegal, it's possible to arrange the kings and up to 34(!) white queens on the board without mate or stalemate looming. At this density, it getting a bit tight, but this thought experiment shows that when we are dealing with merely 18 queens, where moreover friendly queens can shield against enemy ones, there a vast amount of slack, and no need to worry about forced mates or stalemates. Even with 18 queens, the chessboard is a very empty box of cornflakes :-)
Counting the collections
Let's focus on just the White units first. How many legal White collections are there? 8,694. Here's a quick proof.
Let k be the number of visible promotions to rook, knight or bishop (i.e. officers beyond the original complement of 2 for any of these types). (For symmetry reasons, queens are dealt with in a couple of paragraphs instead.)
Let v(k) be the number of different combinations of R,N,B which achieve this.
v(0) = 27:
because there may be 0-2 remaining of each of R,N,B.

For k>0, v(k) = (k^2 + 15*k + 38)/2
e.g.:

v(1) = again 27:
3 ways to pick one of R,N,B to be 3;
& 0-2 possible for each of the other two types.

v(2) = 36:
27 ways to have 4,0-2,0-2;
& 9 ways to have 3,3,0-2.

Then the other 8-k pawns may still be Ps, or turned into Qs, or captured.
Let q be the number of visible queen promotions (i.e. queens beyond the original complement of 1).
Let u_k(q) be the number of different combinatorial ways we can achieve this (in terms of surviving pawns, queens and captured pawns)
u_k(0) = 2*(9-k)
because we can have 0 to 8-k pawns, and the rest are captured,
independently we have 0 or 1 queen.

For q>0, u_k(q) = (9-k-q)

s(k) = sum(q=0,...,8-k) [u_k(q)]
= 2*(9-k) + (8-k) + (7-k) + ... 1
= (9-k)(12-k)/2.

Check:
s(8) = 2: 0-1Q
s(7) = 5: 0P,0-2Q; 1P;0-1Q
...
s(0) = 54: = 55-1

So the total number of of legal White collections is:
sum(k=0...8) [s(k)*v(k)]
= 8,694

All of these white collections are indeed achievable, e.g. if Black has only bare king remaining, but in fact in many other situations too: the supply/demand inequalities are not very demanding.
The next exercise involves counting for each combination of N_w, M_w ,A_w how many White collections exist.
I computed the following table of numbers of collections, sorted according to the total number of pieces on the board, as shown in this table:

For each number of units from 2-32, this shows

v_0: the number of basic candidates without worrying about supply-demand,
v_1: the number who have a single fail against supply-demand,
v_2:  the number who have a double fail against supply-demand.

To avoid double counting, the number of legal positions is computed as v_1 - 2*v_2 + v_3. My calculations match Kryukov's prior results  exactly.
Note that there are no fails until one reaches 25 units. That's because with 8 captures, all candidate promotion collections can be achieved.
An "extra credit" open question (work in progress)
Retro enthusiasts further distinguish between the colour of squares the bishops are on, since that is an invariant. This has a major, visible impact on potential legality, is part of the essential classification for chess tablebases, and is also an aesthetic concern in composition. The corresponding term then is "non-standard officers" (queens or "tinted" bishops beyond the first; rooks or knights beyond the second). The count of missing officers is based on the same 5 types. The determination of which additional inequalities are necessary and sufficient to characterize legal collections is now substantially more complicated.
The best approach may be to first apply the adapted supply/demand inequalities. Then can ask how many extra pawn captures are required to "nudge" certain bishops to the correct tint?
A pawn capture of an officer/pawn will result in a batch of respectively 2/3 pawns all promoted on same tint squares, but it seems that for each such batch, we are free to choose the tint independently.


This puzzle needs more love, so I post my best position (46):
[FEN "8/8/2PN4/1PKB4/2PRNB2/2PRQ1P1/3PPP2/8 w - - 0 1"]

Since just a record attempt is hardly an answer, here some tips for those who want to beat it:
R (and less so Q) are no problem, just put them in the mid of the fray. B can easily have at least 3. K should also have a crowded place. Critical is to have many covers by N and especially by P. Do not bother to count how often a piece is protected when moving around stuff, rather count how many pieces it protects!


Is short castling dangerous in Bughouse?

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

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


Why not solve more Chess puzzles? That will definitely help you.
There are many freemium model chess sites out there..

My favorite is Chessity
Others in this list are:

Chess.com
Chess Tempo

[This list is endless. Other may have suggestions too.]

I'm afraid that playing against computers might defeat your motivation, because they are very good and beat humans without mercy.

I would also recommend playing online with other human folks.
I use Playchess


A tactic on the Chekhover variation of the Sicilian?

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

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

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

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


When you state that you are quite a decent player, exactly what do you mean by that? Do you mean that you have been producing relatively good results in actual chess tournaments, or do you mean that you usually win when playing against casual players? If the first description fits you, then studying opening theory may bring some value. In this case, you should try to understand why the moves are played in the opening instead of just memorizing variations, as the latter won't prepare you if your opponent steps out of theory. Look at famous games played in the opening and reflect over the moves that are played.
(Edit: And as r4 pointed out in his answer: don't be afraid to play the opening a lot!)

In the other case it will probably be completely pointless to study specific opening theory, as there are other things you need to learn first to become stronger. In this case it's better to review the basic opening principles about development, center control, piece activity and king safety, and follow them. In the vast majority of cases they are sound enough to give you an advantage against weaker tournament players, if you master them.


I think the best approach is what I call live annotated chess.  In this case you basically play normally but provide live feedback on the student's position and why you are doing the things you are doing.  This allows you to understand where the student needs additional help and allows them to learn from you.

This approach also allows you to adjust your play according to student needs.  If the student is making a lot of careless errors and doesn't seem too into it, you can tone down the annotation and your game and let them play more for fun.  If the student seems really motivated in a given game, you can introduce more challenge by upping your game and your discussion.

You can even do this within a game if you sense the student getting frustrated or bored.

I would also say that not all chess needs to be played by "chess rules" kids at that age get a kick out of manipulating the world around them. Let them make up new games that still teach chess principles but are not so rigid.  Let the bishops move like queens, or allow them to win back material for consecutive captures, etc...  I don't think these types of things teach bad practice because they let the student experiment with the "world" and understand how it reacts.


Yes.

The search, evaluation, etc., are almost identical to Stockfish, with the notable exception of being rewritten in Dutch. A number of Stockfish developers, including former maintainers, have noted as such. To hide its origins, code was included that multiplied the node count by 8/7. Exploiting modular arithmetic tricks and archived Houdini games, this exact code was shown to be present in the release version of Houdini. The alleged performance improvements over Stockfish go away after removing this trick.

The leaked source code was compiled by Ed Schroder and found to have a 1:1 correspondence with Houdini in a vast number of test positions, while others, like Simon Guenther, have found that the leaked code behaves identically in the start position even up to high depths.

There were changes, but Mark Lefler, developer of Komodo, noted that a number ofaa changes were simply adding features reverse engineered from Komodo. In fact, in one file, evaluatie.cpp, you can spot the naming conventions used by the Hex-Rays decompiler.

Other features were unique, but minor. For example, the licensing system was not from Stockfish. However, the code came from TurboPack and was translated into C++, so it's not clear that that was original work, either.

Adjusting for the time of release, the version of Stockfish on GitHub at the time of Houdini  5's release was more or less equal in strength to Houdini 5. Later, when Houdini 6 was released, this was also true. (Source: nextchessmove's elo data + CCRL data)

In other words, Houdini did not notably build upon Stockfish in any meaningful way. The main reason it looks different is because of the Dutch translation and the fact that Stockfish has evolved significantly since Houdart last touched the Stockfish codebase.


Looking for a good and non main line variation against the Sicilian

It's a bit difficult to recommend an aggressive line that doesn't fall into the variations that you listed. However, I believe there is an option that may suit your tastes. The Rossolimo with 2. Nc3 is venomous choice that's played at the highest levels and contains many lines that are quite dangerous for black. Here's one of the opening traps:

[FEN ""]

1. e4 c5 2. Nc3 Nc6 3. Bb5 Nd4 4. Bc4 e6 5. Nge2 Nf6 6. d3 a6 7. O-O d5 8. exd5 exd5 9. Nxd5 Nxd5 10. Nxd4 cxd4 11. Qh5 Be6 12. Re1

I recommend that you look more into the opening yourself and discover some more interesting lines.


Embedding chess games from PGN in markdown

Well, on this site, you can use the 'replayer'. Basically, you just paste the PGN as a code block; for more details, see Can we implement a replayer for chess analysis on the site?.

For example, the following code will display the first three moves of the Ruy Lopez opening:

    [FEN ""]
    1. e4 e5 2. Nf3 Nc6 3. Bb5

(it doesn't work right here because of the <pre> block in the post source)

But this isn't really converting the PGN into Markdown, it's just Stack Exchange's rendering engine detecting the PGN and converting it into a JavaScript widget. There is no 'official' way of converting PGN into Markdown, just like there is no official way to convert it into HTML.


Can someone explain this endgame puzzleto me with words?

To solve this you need to ask yourself 2 questions:

1) How could the position change so that Black can draw? White must try and avoid this.

2) How could the position change so that Black can no longer protect his pawn(s)?

1) Suppose White just pushes g5. Then Black can never be forced away from the defence of f7. Either the white king will move between e7 and e8 when the black king can just move between g7 and g8 (opposition doesn't matter) or white king will come to f6 when the black king can just oscillate between g8 and f8 and white can make no progress. White must avoid this.

Also if the f pawns end up on f7 (black) and f6 (white) and black can stop white's king getting to e7 then white will not be able to make progress. For example white king on d6 black king on e8 black to move plays Kd8 taking the opposition preventing white progress. On this side black has the space to always keep the opposition. White must also avoid this.

2) If white can achieve a position with the f pawn ahead of the g pawn with the king advanced to the e file one square ahead of the f pawn then black can be continuously zugzwanged into undefending his back pawn and white will win. This is because the white f pawn takes away a square from the black king and stops it triangulating when the white king triangulates.

The same applies if the g pawns come off, the f pawns are locked and the white king reaches the same position.

Another possibility is if the white king can reach the eighth rank and get behind the black pawns because his pawns will be more advanced.

So, the way to start is with Kd5. The aim is to get the king to e7 and then push the f pawn to try and get it to f6.

If black responds with Kf6 then after Kd6 from white black is in zugzwang and we get in Ke7 next move. Then white just pushes the f pawn up to f6.

If black responds with Kf8 or Kg8 then white plays Kd6 and if black keeps his king on f8 and e8 keeping the white king out of e7 then white pushes the f pawn. If black exchanges then white can push up to f7 when black will be zugzwanged into allowing Ke7 when white will win. If black pushes his pawn to g5 then white must not push f6 immediately or black will gain the opposition and it will be a draw. Instead white should outflank the black king with Kc7 aiming for Kc8. Then white can gain the opposition and play f6 if black defends the eighth rank with Ke8. If black abandons the eighth rank with Kd6 then white moves along the eighth rank and takes the f pawn winning.

A cunning ploy by black would be to reply to Kd5 with Kh6 with the aim of f5 if white continues on with Kd6. Then either white swaps pawns and black gets the opposition or white pushes g5+ and black comes round the back with Kh5 and they take each others' back pawn and it is a draw. White must instead reply to Kh6 with Ke5. Then black must play Kg7 to stop the white king coming in to f6. Now white plays Kd6 and we are back to plan A.

So, the problem relies very heavily on zugzwanging black in positions where the advanced white f pawn takes away a key square from the black king and also the idea that once the white f pawn is advanced if black abandons the eighth rank then white takes it and wins the black f pawn and will queen well before black.


It doesn't work because there's a bug. If you open the console (F12 → Console) you'll see some errors. It seems that an essential file is missing from the server. Until it is fixed, you should probably use another analysis board.


I believe it helps to focus more on enjoying the game rather than learning. If you enjoy the game, you learn a lot in the process.

So, my advice would be to enjoy your chess. Find players that are roughly your skill level and play many games. Once you've played a few dozen games, you will gain some experience and then you will be ready to start learning chess in a formal way - reading books, articles, listening to video lectures, etc.

As of today, I am about as strong as a Candidate Master. I will tell you how I learned the game. At first, as a kid, me and my dad would just play for fun. My dad would often let me win and I would enjoy it. Then, when I was about 9 or 10, my dad took me to a few tournaments (no age group) and I was surprised that I could beat a few players who were older than me. Up until this point, I had no formal training (my dad was just an amateur player), but then one of the arbiters of the tournament offered to help me learn and then I would go to his place quite often and play a few games with him. After each game, he would show me the mistakes I made and what I needed to learn from that game. He told me about general opening principles, but his main focus was the endgame. He told me that it's very important to know the endgame. After that, I also learned a few openings, mostly by going over the games of stronger players and observing the types of moves they made. I didn't simply copy their openings, but I tried to play like them and incorporate their ideas into my game, as I understood them.

Then, I continued playing in tournaments and gradually my playing strength improved because my tactics improved, my endgame knowledge improved, my knowledge of chess strategy improved and so on. I also began to analyze my own games with the help of a computer. Before I had a computer, I would analyze them by myself (believe me, this helps you become a better player even if your analysis is actually wrong!). Overall, I enjoyed the game and in the process I learned quite a bit and now I'm aspiring to be a FIDE Master in the near future.

Here are a few books I recommend that you get hold of (this is after you have first played a lot of games and gained some experience)-

Understanding Chess Endgames by John Nunn

Winning Chess Openings by Bill Robertie

The Most Instructive Games of Chess Ever Played by Irving Chernev

Good luck to you!


What is a good, aggressive response against the Sicilian Defense?

The Open Sicilian (2.Nf3 and 3.d4) is the most aggressive way to attack the Sicilian, as white immediately opens up the position for all his pieces and gets a nice knight on d4. Black has trumps, but first he lags in development and his advantages typically only start counting if he survives white's attack. It is also the best reply, or at least it has consistently been the most popular reply to the Sicilian on higher levels since forever.

So I think that it's really the only correct answer to your question, which asks for the most aggressive and best response to the Sicilian.

That said, it is not the easiest. Black has like ten different ways to react to the Open Sicilian, and although white gets great chances of an attack in almost all of them, they are all different and often black knows them better than white. Spending loads of time learning everything is probably not the most efficient way to improve your chess right now. That is a general thing with chess, and life -- ambitious, good and easy, choose two.

You say "I have had good wins with this system but also crushing defeats". That is good, that is exactly what you expect from aggressive openings, it seems to me.

You also say "I am looking for a more aggressive response, since it fits best my style." That is less good. At top level, having a style at all is a sign of weakness, as it means you are biased. But you're 1500, you don't have a style. You simply have some parts of the game that you are bad at and some parts that you are less bad at. You should be busy identifying things you're bad at and working on them, not worrying about your style.

And, last, losing some games is the worst reason to switch openings! You'll just lose some more games in the next variation you chose, switch again... The Grand Prix is a decent variation, it didn't cause your losses. You made mistakes later on. Find out where, and do better next time.

Understand what happened more generally -- what plan did you choose, how did you expect it to work, why didn't it, is that a problem in general or is it just because of the moves he happened to play this time, in what kind of situations would it work? What other plans are there? Find example games. Regularly switch variations inside the Grand Prix attack, that way you'll see more typical positions and if your opponent does something unexpected, you'll have broader experience to draw from.

Become an expert in your Grand Prix.


The type of complex tactic you are thinking of is called a combination. A combination is a forcing series of moves to create some sort of advantage; some would also say that a combination must begin with a material sacrifice, but this is besides the main point. If you are interested in combinations, look at the games of Mikhail Tal, for one, who has been called "the wizard of combinations" for his daring, speculative sacrifices which often led to his opponent cracking under the pressure of searching out the one saving defensive resource; or Alekhine, "the genius of combinations", whose combinations, if not as daring as Tal's, were perhaps more sound.

Wikipedia gives the following example of a combination:

r1b2r2/p2p2kp/1pn1p3/8/1PP5/P2K1P2/2Q4P/R4B2 b - - 0 1

1... Rxf3+ 2. Ke4 (2. Ke2 Nd4+) (2. Kd2 Rf2+ 3. Be2 Rxe2+! Kxe2 Nd4+) d5+!! 3. cxd5 (3. Kxf3 Nd4+)  exd5+ 4. Kxd5 (4. Kxf3 Nd4+) Be6+ 5. Kd6 (5. Kxe6 Nd4+) (5. Kxc6 Rc8+) (5. Ke4 Bf5+) Rd8+ 6. Kc7 (6. Kxe6 Nd4+) (6. Kxc6 Rc8+) Rf7+ 7. Kxc6 Rc8+

In light of the impending disaster, White in fact resigned on move 3 (Move 22 in the actual game between G. Stepanov and Peter Romanovsky).


how do some players focus better by thinking on the first move?

Two big reasons:

At higher levels, a lot of preparation may be done for a game, especially if you know in advance whom you'll be playing. You'll want to prepare responses to all of their most common or strongest lines. You might also have novelties or uncommon ideas in certain lines to throw your opponent off-book. There is a lot to remember, and using five to ten minutes at the start of the game, when you're not under any pressure, to recall all your preparations can be very helpful.
Somewhat related, when you sit down for a game, you're often coming from some very different activity: eating, chatting, or kibitzing other games, for instance. You don't want to start playing while you're still distracted or thinking somewhat of other things, so you can take some time--again, while not under pressure--to get into a "chess mindset". This sounds to me like what your colleague was referring to.

I think there's a decent analogy to more typical "physical" sports, here. Before a basketball game, the teams take several minutes in their locker rooms, stretching out, going over the game plan, and "getting in the zone". They need to make sure they're properly warmed up and ready to hit the floor at full speed when the game starts.

The first move of a Chess game can be used in the same way. Just as basketball players need to warm up their muscles, Chess players may benefit from "warming up" their visualizations and calculations, by reviewing lines and tactics and so on.

As with any pregame routine, the exact techniques will vary widely from person to person, but the goals are always the same: get warmed up, get in the zone, and get ready (mentally) for some fierce competition.


Are you looking for setting up two engines playing against each other? In that case you can use the following in Arena 3.5: Engines > Tournament.


What is the strategic significance of the English Opening?

Since I was playing the English myself, I can tell you why I have found it a good opening for me:

Transpositional potential of this opening is stunning! You can lead your opponent out of his/her opening and draw them into the variations they do not know. One small example: 1.c4 c6 Since Black reveals to us that he plans to play Slav/Semi-Slav/Queen's Gambit we can steer the game into Caro-Kann with 2.e4!?. Now, this means nothing objectively--we just left one opening to enter into another--but the psychological effect can be devastating! It can lead to such consequences like deflating their will to play the game since the game is "boring", or you can actually transpose into an opening your opponent does not know and quickly demolish him.
The center remains fluid for a long time. This is truly gold in the hands of the experienced player and answers this part of your question:

  why it leads to fantastic games?

You see, since White restrains himself in the center, it is usually safe to play on the wings. Black usually responds by playing on the wings too, but inexperienced players forget about counter attack in the center. This possibility requires good calculation and accurate evaluation of the current position in order for a player to be able to execute this properly. Action on one wing + counter-attack in the center = crazy game. Launch your counter-attack in the center at the proper moment and you will win the game most of the time.

These are the beauties of this opening:

Its intolerance for "robotic play" and opening memorization--it requires of a player true knowledge. You must know how to play chess--opening, middle game and end game--no opening book can save you if you do not know how to play chess.
Its main feature is to give so much space to a "true" player for creating winning chances. If you are creative enough you can win in the opening, middle game and even an endgame. By "true" player I mean player who plays every game with 100% of his strength. The player who plays with knowledge and does not rely on safe patterns/30+ memorized opening moves and so on. The player who is willing to fight for victory to the very end.

Whether you play "normal" lines, or you play some side-line/transposition, the English opening will never be dull and sterile for a player who is prepared to invest all of his mental capacity to win the game.

Hopefully this answer will help you.

If you have further questions leave a comment.

Best regards.


Looking for website for organising private tournaments with swiss system?

The related question How to organize a chess tournament appears to have several suggestions; I'm not personally familiar with any of them, but most of the links seem to still be active.


Can you claim an illegal move in Blitz after pressing your clock (but without making a move)?

This is correct. You cannot continue to play (press the clock) and claim a win in blitz. Furthermore in the new rules pressing the clock without making a move counts as an illegal move and so loses (if your opponent claims). This is really just another twist on the old error of taking your opponent's king when he leaves it en prise which again results in you losing for an illegal move instead of your opponent.

In other words, if your opponent makes an illegal move in blitz just claim the game. If you start doing other move-like things (touching a piece, pressing the clock) your claim goes away.

The problem in your case is the same, by the way. An illegal move is only punishable once it is completed by pressing the clock. When you pressed the clock you removed the evidence for the illegal move.


Why does the FIDE rating table go beyond 400?

Why are they there in the first place if they cannot be used?

They were there in the first place because they were used. The 400 point rule came later.

  What use are those entries?

They provide interesting historical context which makes it easier to answer questions like this.

Perhaps a better question would be, why are they still there, or why weren't they removed when the 400 point rule was introduced. There are two obvious answers:

Inertia. It would take effort to remove them
Efficiency. If the 400 point rule is rescinded at some stage then the entries required are already there.


Komodo 9.3 evaluates the position after 1.Kd5 (after searching to 31 ply) as +2.32 for White. Playing out a few lines, White usually ended up with Q+2P vs Q+P. It's not necessarily winning (Q+P endings have lots of resources for the defender due to all the checks) but I am comfortable asserting that the position is more pleasant for White.

For what it's worth, the position has occurred 6 times in my database, with 4 White wins and 2 draws.


Notable decisive grandmaster-level games where only pawns were captured?

Last week GM Nigel Short tweeted:

  Not sure I have won too many games without a single piece or pawn being captured. Short-Derakshani, Beautiful Minds Krulich Cup, rd 10.

I can't find PGN of that game yet and am at work, but you can replay it at https://chess24.com/en/watch/live-tournaments/krulich-cup-2016/10/1/1 - all 32 pieces still on the board, until at move 20 black removed the last escape square of his own queen. After 21.Ng2 attacking it, black resigned.

Moves, taken from here:

[FEN ""]
1. c4 e5 2. e3 Nc6 3. a3 Nf6 4. Nc3 g6 5. d3 Bg7 6. g4 h6 7. Bg2 d6 8. h3 Be6 9. Nd5 Qd7 10. Ne2 Nd8 11. b3 Nh7 12. e4 c6 13. Ne3 Qe7 14. Bb2 Bd7 15. d4 O-O 16. d5 c5 17. Qc2 Qh4 18. Nc3 b6 19. O-O-O Nb7 20. Bf1 Ng5 21. Ng2 1-0


How do I politely ask a spectator to stop watching my game?

Inform the arbiter that it's affecting you, that's more or less all you can do.

Other players in the playing hall and spectators if they're allowed in are allowed to watch your game. But not to interfere with you or distract you.

So if the spectator goes over the line, the arbiter can tell him to take more distance, or leave the playing area. But by itself the fact that he is watching isn't enough, I'd say.


How old was Judit Polgar when she learned to play chess?

In her TED talk Giving checkmate is always fun, Judit Polgar says (t=0:59):

My mother taught me the first moves when I was about five years old...


Why does Stockfish suggest capturing a bishop in this position when my opponent can fork my king and rook?

White does indeed fork the king & rook after Nc7+ - but after Nxa8, the knight is not escaping, so Black is at worst even on material.

 [FEN ""]

 1. d4 c5 2. Nf3 cxd4 3. Nxd4 Nc6 4. Nc3 e5 5. Ndb5 Bb4 6. Bg5? Qxg5 7. Nc7+ Kd8 8. Nxa8

After something like ...b6 followed by Bb7, the knight's a goner. White can get at most one pawn for the knight (after Nxb6), which leads to a material imbalance of R+P vs B+N. This particular imbalance is roughly equal, although I've also read that the side with two minors tends to be favored in middlegames since they represent two useful attacking pieces while the extra pawn is only useful in the endgame. Moreover, Black is also way ahead in development (even if he does take some time to round up the knight on a8).

In short, you're not missing anything important insofar as White does not end up grievously behind in material - but Black has more than enough positional compensation.


Using Stockfish in c# android (xamarin) app

Reusing C++ classes in C# is annoying but straightforward. You'll need to know managed C++.

  https://stackoverflow.com/questions/855756/difference-between-native-and-managed-code

gives you what managed C++ is. It is a C++ technology invented by Microsoft, and it works as a layer between C# and unmanaged C++.

There is no reason why you can't do it in C#. You may want two background threads. The first one sends UCI commands to the engine, while the second thread asynchronously wait for engine results.

EDIT

Steps you should follow:

Read what managed C++ is and why you would need it
Make sure you can compile your unmanaged C++ code (regular C++). How to do it depends on your environment
Make sure your can also compile managed C++ code.
Make sure your C# code can call into managed C++
Make sure your managed C++ code can call into unmanaged C++
Now, you should be able to pass a PGN string from C# to your unmanaged C++ UCI parsing code

There is no reason why you can't use the Stockfish engine in Android.