Tournament strategy to gain maximum points

I find dfan's answer the best posted, but I want to add a few things that I think should be considered:

Against players signifigantly weaker than you - PLAY SOLID CHESS! These players will unwittingly outplay themselves if you let them. You have to be patient, and not give them any chances to actually get anything sharp going. Just hoist them up gently after they've tied the noose around their neck.
Against players roughly at the same level as you (1600-1700), offbeat openings may actually give you an edge, if you're familiar with them. But don't try to play something unsound just to confuse your opponent. Remember that you cannot expect the game to be over just because you got out of the opening with an advantage. And focus on playing well - the game will most likely be decided by who was more tactically alert.
Against strong players, you should only be happy after you've won the game, and not because you won a pawn/piece in the opening. These players are greedy (and strong) enough to rip off your arm if you lend them a finger, so do not relax, even if you have a great position. Also, try to decide the game before the endgame if possible. A CM will most likely outplay you in an equal endgame, so go for "high-risk-high-reward" openings, since anybody can make fatal mistakes in sharp positions. Avoid slow, positional setups. Be prepared that these players will do to you what you should do against the weaker players. They will not be as easy to fool with uncommon setups as the others, and even if they are fooled, it may not be enough.


Why are chess.com opening names and notations seemingly mismatched?

I think this is intentional. The opening name alludes to the position reached, not the route taken to get there. The principal move order to reach this position is to start with the classical variation of the Spanish variation of the four knights game and play 5. O-O.

It wouldn't make sense to say Four Knights Game: Spanish Variation, Classical Variation, 4. O-O because if you had reached it from that route then you wouldn't have castled on move 4. While it would make sense to describe it as a Ruy Lopez with 4. O-O, it would be undesirable to list the same position under two different openings.


After 4....Qf6, both 5.Be3 and 5.Nxc6 are likely to transpose to 4....Bc5: 5.Be3 Bc5 and 5.Nxc6 Bc5. Instead, 5.Nf3 seems to be an interesting alternative, with chances to obtain an advantage. It worked quite well for Giri, as he was pressing the entire game.

After 5.Nf3, black should probably be able to equalize. Andreikin played the precise 5....Bb4+ and the game continued 6.c3 Bc5 7.Be2 d6 8.0-0. Black followed up with the logical 8....Nge7, but ended up in a worse position after 9.b4 Bb6 10.Bg5. Note that 9....Nxb4 or 9....Bxb4 doesn't work because of 10.Bg5. Instead, 8....a6 and 8....Qe7 (to play Nf6) are probably better alternatives, after which black should be able to keep the balance.

Actually, one can also wonder why black would give white the opportunity of 5.Nf3 by playing 4....Qf6 instead of 4....Bc5.
Two possible reasons are:

After 4....Qf6 5.Nxc6, black wants to play 5....dxc6, instead of 5....Bc5. This way, he can still chose between Bb4, Bc5 or Bd6.
Black doesn't like the position after 4....Bc5 5.Nb3 Bb6 6.Nc3 Nf6

      [StartPly "7"]

      [FEN ""]
      1.e4 e5 2.Nf3 Nc6 3.d4 exd4 4.Nxd4 Qf6 (4...Bc5 5.Nb3 (5.Be3 Qf6)(5.Nxc6 Qf6) Bb6 6.Nc3 Nf6) 5.Nf3 (5.Be3 Bc5)(5.Nxc6 dxc6 (5...Bc5)) Bb4+ 6.c3 Bc5 7.Be2 d6 8.O-O Nge7 (8...a6)(8...Qe7) 9.b4 Bb6 (9...Nxb4 10.Bg5)(9...Bxb4 10.Bg5) 10.Bg5


Can a GM title be given to someone after he dies?

Yes, it is possible. FIDE can award the title of honorary grandmaster, based on a player's past performances and/or other contributions to chess.

Most of the honorary grandmasters were still alive when they were awarded the title. However, there are two examples where the title was awarded posthumously:
GM Rudolf Maric and GM Karoly Honfi.


Trapped Rooks: Does Stockfish penalize more if the king can't castle temporarily?

White hasn't lost his castling rights. It's just not a legal move right now. There is a distinction.
White would still be able to castle king-side, if the bishop were to move.


How do chess engines decide which best line to play when the game outcome is within their horizon?

If the engine can choose between getting mated in 2 or mated in 3, it'll choose the line where it is mated in 3 (even though the mate in 2 might be 'more difficult' to spot for humans).

It can't really set traps, because it doesn't know what things might be difficult to spot for a human (or other engine) opponent. It just evaluates the position, without really knowing it's playing a game against somebody; a notable exception is the implementation of contempt, basically a slight modification of the evaluation in order to prevent drawing too early.

For example, in Stockfish, scores for won or lost positions are computed with the function mated_in (and, more rarely, its negated form mate_in).  As you can see in the code, a loss is scored as a large negative value plus the number of ply until the loss, so the engine favors winning lines that are fast and losing lines that are slow.

The tie-breaking for draws is usually arbitrary.  For instance, in Stockfish, scores for drawn positions are either the constant VALUE_DRAW or computed by the function value_draw to be VALUE_DRAW plus one or plus two.  The bonus depends on the thread's node counter, which is essentially up to luck, so the variations in scores for drawn positions are not really based on the positions themselves.  This small bit of noise in draw scoring is more to keep the search from fixating on certain three-fold repetitions than to help it choose among lines.


How can I know the Elo rating of my chess engine?

Easy question. Announce your engine on the chess programming forum (http://talkchess.com/forum/index.php). There'll be engine testers adding your engine to their rating list, such as CCRL. But please and please provide a working compiled binary.

Announce your engine, upload a compiled binary to somewhere like Dropbox. You'll hear feedback.

EDIT

cutechess is a popular tool for automating computer engine-to-engine matches. The only and only way to test your changes is to make your engine to play games. You can make it to play with an older version or another engine.

https://chessprogramming.wikispaces.com/Cutechess-cli


Stockfish draw value randomization and "3-fold blindness"

I would first like to acknowledge that this answer is somewhat speculative; this is the first time I've seen this feature in a a chess engine, and I'd be interested to know what other chess programmers think of my answer.

Contrary to what is commonly believed, (good) chess engines don't just "search all possible moves" up to a certain depth then pick the best one. If we were limited to this, modern engines would only be ~1600. An incredibly, stupidly important idea in chess programming is that of "reductions." There are many different types, but the basic idea is that computers don't search some lines it doesn't consider promising.

Of course, this is a very double edged sword. On the one hand, you get much deeper and more effective searches, but on the other you are destined to miss something. To give you a taste, consider the following position:

[FEN "3n3k/rp4pp/1p5r/pPp1pp2/PpPp1p2/3PpPp1/RN2P1P1/QBNR1BK1 b - - 0 1"]

I'm confident a reasonable player can find the simple mate for black (get both rooks on the h file, and mate on h1, after Ne6 to ensure that White cannot break through), but Stockfish 10 can't find it at "depth 50". This happens because the mate involves like 7 consecutive quiet moves, which Stockfish doesn't see as significant enough to warrant intensive search. (Another example on Lichess.) When engines miss tactics, most of the time something like this is to blame.

One of the most common forms of this technique are "late move reductions," wherein the computer selectively reduces moves found later in the move ordering. (this sorta presupposes you have semi-decent move ordering, but you said you already knew a little of that, so we're skipping it).

Next, iterative deepening. Basically, the idea is that if you ask Stockfish to search at depth 25, it will start by searching depth 1, then depth 2, then depth 3,... then depth 25. This seems like a stupid idea at first, but it has various benefits most of which I won't go into. What's relevant here is that the depth 24 search informs decisions about reductions the depth 25 search makes. So if depth 24 says a move isn't too promising, depth 25 is less likely to search it deeply. (this is a massive simplification).

Ok so what's happening in the commit?

  The effect is that in positions with many 3-fold draw lines, different lines are followed at each iteration. This keeps the search much more dynamic, as opposed to being locked to one particular 3-fold.

Here's how I'm reading this: Before the commit, the computer will be searching the same draws at every iteration. If there are lots of 3-fold lines, it's possible the computer won't search all of them (or at least, all of them deeply). This can lead to "blind spots," where the computer doesn't notice some sideline in a move with a draw score.

Before the commit, each successive iteration would have (roughly) the same blind spots (albeit with more resources to notice the sideline). After the commit, the blind spots are scrambled at each iteration, making it less likely to miss the sideline.

As a toy hypothetical example (which shouldn't be taken too literally): say we have two "draw" moves A and B, both of which are way out at the horizon of the search. Because they are so far away, the computer's evaluation of them is very bad (for several reasons, but for the time being we can just think that only a few of A and B's children are searched due to reductions) so it's possible A and B aren't actually draws.

Now for whatever reason (perhaps reductions), let's say the computer has allocated 5 resources to search the "best" draw move and 3 resources for the "second best" draw move at iteration 24, while allocating 6 and 4 respectively at iteration 25.

Let's also say A is a genuine draw, but B has a sideline which isn't, and will be noticed if it is searched with 5 resources.

Before the commit, if A is searched first at iteration 24, it will likely also be searched first at iteration 25 (meaning the sideline slips through), but after the commit, A and B are equally likely to be searched at each iteration, meaning the sideline is more likely to be found at some iteration, whereupon the computer will take note and correct.

I don't know if that made any sense whatsoever, but I hope it helps.

Again, I'm very open to being corrected here. This is just my reading of the commit.


The engine is giving you an answer. Black plays ... Na5 followed by ... Nc4 which prevents White from bringing pieces over to the queenside, because of the White doubled pawns on c2 and c3. Which means the White king is now stranded by itself on the queenside.
Black is going to play ... c5 and bring the queen out to a5 or b6. On a5 it threatens ... Qxa3 with mate to follow. On b6 it's threatening ... Qb2 with mate.
What queenside castling has done is to put the White king into the line of fire, in a way that Black has at least two pieces converging to attack, and White has none. Even, if by miracle, White gets some pieces over to the a- and b-files, Black's other pieces will enter the fray much quicker and in much larger numbers: The a8 rook by pushing the a-pawn, the c8-bishop via d7.
The chess engine reckons White is going to lose at least a rook to stave off this attack (this is simply the difference between the position evaluation after queenside castling -6.27 versus the best move Nf3 which is evaluated to -1.74).
In logical terms, you castled into an attack on the queenside. With the centre as constricted as it is, your king was fairly safe remaining in the centre uncastled for the time being. You needed to develop the Knight to f3, and the bishop to e2, and take it from there.


I'm not aware of an API, but they way they have it set up it's pretty easy to gather data via a technique called screen/web scraping.

For example, a search on your name gives a link to a specific page with your member id in the URL. Then if you have a programming language/library that is DOM-aware, you can simply figure out where certain things will be, based on the design of the page. Using jquery selectors, and a couple of traversals, that page can be parsed to get the rating as such:

> $("td td td:contains(Regular Rating)").next().find("nobr").text();
"2072
2012-03(Current floor is 1800)"

Nice rating, by the way.

It's a bit painful, and even more painful if they ever decide to change the design of the pages, but eventually you'll be able to parse out all the data you want, and then build a way of collecting data for each member and storing it in your own database for analytics. It wouldn't be that hard to do, just iterate through member ids, and you can get their names, states, ratings, etc.--as much is available on their screens.

Hope that helps.


To answer your question: There are computer accounts in FICS, with handles ending in (C). Also guests may be computers. There might be computers also behind other players, but that's against the rules of FICS. Engines can be connected to FICS using icsDrone, XBoard/WinBoard with Zippy, or similar tools.


What’s the point of early ...a6 move in Queen’s Gambit Declined?

It is hard to tell exactly without an exact line, but normally it has the idea of following with ...dxc4 (putting the enemy bishop on the c4 square), ...b5 (now kicking it away) and ...Bb7.

This solves the annoying problem of placing the c8 bishop on a decent square


About 12...Bg5 and move orders in the 9.Nd5 Sveshnikov

Black would be thrilled if White exchanged his perfectly-placed knight on d5 for Black's bad bishop on f6. 12...Bg5 brings it to a diagonal where it's actually doing something and also makes it possible to eventually play ...f5, undermining the pawn supporting White's knight.

White doesn't play Nxf6 earlier because he'd be exchanging a well-placed piece for a badly-placed one. Note that if Black plays alternative moves on move 12 like 12...Bb7 or 12...Rb8, White still doesn't play 13.Nxf6.


How do you hold a draw with a knight against a rook?

The weaker side needs to keep Knight close to his King in order to achieve draw.

There are some special cases where the stronger side wins even in those situations, like when Knight is cornered or pinned in such a way that puts weaker side in zugzwang.

If the Knight is far away from the King then the result of the game depends whether or not the defending side is able to connect his pieces.

Here are some demonstrations:

Typical example:

[Title "Rook vs Knight, typical drawing plan"]
[fen "3nk3/2R5/8/4K3/8/8/8/8 w - - 0 1"]

1.Kd6 Nf7+! ( 1...Kf8?? 2.Rc8 Ke8 3.Ra8+- ) 2.Ke6 Nd8+ 3.Kf6 Kf8 4.Rd7 Ke8 ( 4...Nc6?? 5.Rd6+- ) 5.Re7+ Kf8 6.Re1 Nb7 7.Ke6 Ke8 8.Rb1 Nd8+ 9.Kd6 Nf7+ 10.Ke6 Nd8+ 1/2-1/2

It is useful to mention that in these position the defender should not allow vertical opposition( e6-e8 in the above example ), but should strive for the diagonal one( e8-f6 or e8/d6 ).

Even in the following position, Black is able to maintain a draw:

[Title "Drawing plan in a difficult position"]
[fen "5nk1/4R3/8/6K1/8/8/8/8 w - - 0 1"]

1.Kf6 Nh7+! 2.Kg6 Nf8+ 3.Kh6 Kh8 4.Rf7 Kg8 5.Rg7+ Kh8 6.Rg1 Nd7! ( 6...Nh7?? 7.Kg6! Kg8 8.Rg2 Nf8+ 9.Kf6+ Kh8 10.Kf7 Nh7 11.Rg8#) ( 6...Ne6 7.Kg6! Nf8 ( 7...Kg8 8.Kf6+! ) 8.Kf7 Nh7 9.Rg8# ) 7.Kg6 Kg8 8.Rd1 Nf8+ 9.Kf6 Nh7+ 10.Kg6 Nf8+ 1/2-1/2

Winning motifs for the stronger side:

We already saw one above-the decisive pinning of the knight that leads to zugzwang:

[Title "Decisive zugzwang"]
[fen "R2nk3/8/3K4/8/8/8/8/8 w - - 0 1 "]

1.Rc8 Kf7 2.Rxd8+-

These motifs happen due to bad positioning of the King:

[Title "Defenders pieces are badly positioned : Cornered King"]
[fen "6nk/5R2/8/7K/8/8/8/8 w - - 0 1 "]

1.Kg6+- ( 1.Kg5+- )

or badly posted Knight:

[Title "Defenders pieces are badly positioned : Knight is away from his King"]
[fen "5k2/3R4/2n2K2/8/8/8/8/8 w - - 0 1"]

1.Rd6 Ne7 2.Rd8# 1-0

Another important motif is cornering the Knight :

[Title "Cornered Knight"]
[fen "6k1/5n2/6K1/8/8/3R4/8/8 w - - 0 1 "]

1.Rd5! Nh8+ 2.Kf6 Nf7 3.Rd7 Nh6 ( 3...Nh8 4.Ra7+- ) 4.Kg6+-

Sometimes defenders units are not badly placed but just separated. In that case stronger side can win if it can push Knight away from the king since then it will be able to trap it. Here is an example:

[Title "Knight is too far from his King"]
[fen "8/8/8/2k1K3/8/3R4/4n3/8 w - - 0 1 "]

1.Re3! Ng1 2.Kf5! ( 2.Kf4? Kd4! 3.Re1 Nh3+ 4.Kg3 Ng5 5.Kf4 Nh3+= ) 2...Kd4 3.Kf4 Kc4 4.Kg3 Kd4 5.Re1+-

SUMMARY:

The defender must keep his pieces together and avoid being cornered. Maintaining diagonal opposition with kings is desired.

The stronger side has several winning motifs:

Corner the opposing King and then execute double attack with the rook which threatens mate and attacks the Knight.
Corner the Knight and create zugzwang.
Push away the Knight as far away as possible from his King and then trap him.
In some special cases, exploit bad piece coordination to create decisive zugzwang.

NOTE:

Examples and instructions are taken from the book:

Y.Averbakh - Comprehensive Chess Endings Volume 2.

Best regards.


Opening Moves: Pawn Chains and Countering Attacks

It is, indeed, called a "pawn chain". It does not have any other special designation. There is no single best way to counter any specific pawn chain, as it is much more complex than that. Here is a bit on that.

Pawn chains, and where you attack them, is the basis for all opening play. Where the pawns on both sides clash is called a pawn break. Knowing where your pawn break is, and which one is feasible, is the difference between having a freer game for your pieces, and being smothered to death.

Part of that is also knowing if you should extend the pawn chain, and thus, change the point of attack for your pawn break.

  [FEN ""]
  1. e4 e6 2. d4 d5 3. e5 c5 4. c3 Nc6 5. Nf3 Nge7 6. Bd3 Nf5 7. O-O Be7 8. Bc2 c4? 9.b3 b5 10.a4

Here extending the pawn chain, intending b5-b4, is too slow due to the undefended rook on a8. The q-side is about to open up much to white's favor.

You have to realize that changing the pawn break, and moving it up one file, while usually great in principle, it also is much slower, so especially if your pawn break is on the q-side, and your opponent is breaking on your k-side, his could become much more dangerous much more quickly.

Learning about opening pawn structures, and the pawn breaks associated with them, can be learned in the following books:

“Complete Chess Strategy” volumes 1,2 and 3 by Ludek Pachman. (This teaches about many basic plans, and what you are striving for with your pieces and pawns, especially. THIS is what made me a master.)
“Pawn Structure Chess” by Andy Soltis. (This extends the above to specific opening structures.)
“Chess Structures: A Grandmaster Guide” by Mauricio Flores Rios (This is an extension of “Pawn Structure Chess”, and is deeper, and covers more structures. It is outstanding especially if you have already covered “Complete Chess Strategy”.)

Here is a good link with some basics.


Chess engine: Quiescence Search increases required time by a factor of 20

Because you said

  Without limiting the allowed depth of the Quiescence Search, my program ran for multiple minutes without any result

I'm assuming that you haven't implemented any capture ordering in your quiescence search.

When you don't do this, you allow your computer to calculate rather silly situations very deeply. For instance, say I have one capture: my queen takes your (defended) pawn. This is obviously a bad choice, and we want your computer to recognize this quickly.

You could simply recapture (choice A), but you have another capture available (choice B) your bishop takes my pawn. Say for the sake of example that these are the only two available captures. You now have two options for searching these moves:

First B, then A

If you search B first, my queen might have the option to take another piece (now that it has moved to a different square). You'll call the quiescence function again (maybe your bishop can now take another piece) and after that, maybe my queen can take yet another piece. You're calling the quiescence function over and over again. It'll have to end at some point, but when you're doing this for every leaf node, this takes time.

First A, then B

If you search A first, I will no longer have a queen with which to take pieces, meaning I am substantially less likely to have to have more captures available, meaning your quiescence search will likely stop here. Then, when you inevitably search B, you will be much more likely to create a beta cutoff because capturing the queen with a pawn was given a very high value.

Hopefully this illustrates the importance of move ordering in quiescence search.

The way we typically do this is with MVV/LVA, which stands for "most valuable victim, least valuable attacker," which does exactly what it sounds like. For each capture, compute the value of the victim minus the value of the attacker, then search the largest captures first. This should massively reduce your qsearch times.

All this being said, limiting your qserach is sometimes a legitimate thing to do, (is it actually useful to see the 10th capture in a row?) but first you should see how the capture ordering shakes out, then make a decision.

Hope it helps.


When ... Qxb5 is played, White can play Bxd6. This is a great spot for the bishop, because now your opponent can't castle and your bishop is controlling some nice squares. If Black doesn't capture on b5, then he pretty much needs to move his queen, since you're threatening it with that bishop. Once he retreats, you have another piece developed, while your opponent has wasted a move running away.


I set out to answer my own question with the help of two computers. A Dell desk top using Windows 7 and a Dell laptop using Windows XP. The desktop used Deep Fritz 12 and Fritz 11 was used on the laptop. I played the London opening against Deep Fritz 12 and it appeared to use the Semi-Tarrasch.  After I set-up the opening in Fritz 11, Deep Fritz 12 lost to Fritz 11. I wanted to try the Queens Indian. The second time I played the London system against Deep Fritz 12 Deep Fritz wanted to play the Grunfeld. I had to force it to play the Queens Indian. After 51 moves Fritz 11 resigned.

[Event "Blitz 45m"]
[Site "Independence"]
[Date "????.??.??"]
[Round "?"]
[White "Gyr_man/Fritz 11"]
[Black "Deep Fritz 12"]
[Result "*"]
[PlyCount "80"]
[TimeControl "2700"]
[fen ""]

1. d4 {0} Nf6 {0} 2. Nf3 {0} e6 {0} 3. Bf4
{0} b6 {0} 4. e3 {0} Be7 {0} 5. h3 {16} Bb7 {3} 6. Be2 {166} d5 {217} 7. Nc3 {
154} O-O {0} 8. O-O {134} c5 {0} 9. Ne5 {186} Nc6 {0} 10. Bb5 {151} Rc8 {0} 11.
a3 {70} cxd4 {83} 12. Bxc6 {90} Bxc6 {0} 13. Nxc6 {167} Rxc6 {0} 14. exd4 {97}
Bd6 {21} 15. Qd2 {61} Bxf4 {171} 16. Qxf4 {14} Qc7 {275} 17. Qg5 {155} Ne8 {123
} 18. Rfd1 {63} Nd6 {179} 19. Qg3 {6} Rc8 {60} 20. Ra2 {66} b5 {87} 21. Qf4 {52
} a5 {131} 22. Raa1 {10} Qd8 {122} 23. Rab1 {70} h6 {39} 24. Ra1 {70} Rc4 {177}
25. g3 {12} g5 {26} 26. Qf3 {63} Kg7 {0} 27. Kg2 {39} b4 {1} 28. axb4 {63} axb4
{0} 29. Na2 {53} Rxc2 {18} 30. Nxb4 {39} Rxb2 {0} 31. Nd3 {105} Rbc2 {0} 32.
Nc5 {100} Nf5 {45} 33. Qd3 {33} Rc4 {0} 34. Rdc1 {20} Ra8 {11} 35. Rxa8 {23}
Qxa8 {0} 36. Nb3 {34} Qa4 {34} 37. Ra1 {22} Qb4 {57} 38. Ra7 {11} Qb6 {40} 39.
Ra2 {20} Qc7 {5} 40. Qd2 {0} Nxg3 {29} (40... Nxg3 {7} 41. fxg3 {41} Rc3 {0}
42. Qf2 {59} Rxb3 {0} 43. Rd2 {22} h5 {38} 44. Rb2 {39} Rxb2 {2} 45. Qxb2 {19}
h4 {17} 46. gxh4 {8} gxh4 {27} 47. Qf2 {11} Qg3+ {7} 48. Qxg3+ {33} hxg3 {0}
49. Kxg3 {14} Kg6 {1} 50. Kf3 {26} Kg5 {4} 51. Kg3 {27} Kh5 {4}) *


For a beginner, the goal of the opening is simply to avoid losing material and blundering; don't stress playing a perfect opening just yet. However, here are some general (and not at all exhaustive) distinctions between the openings:

e4

Often leads to open games
Bishops are slightly more valuable, as they have more space on the board to play
Through the midgame towards the endgame, entire files may be left open - because of this, Rook positioning is key and often can be make or break
Openings to study: Ruy Lopez, Sicilian (although I'd avoid playing the Sicilian as a beginner)

d4

Often leads to more closed games
Bishops and Rooks are relatively immobile throughout the midgames, and serve passive (but still important!) roles
Knights form the basis for strong attacks and exerting control in the center of the board
Openings to study: Queen's Gambit, Indian Defenses (fianchettoed bishop)

Ultimately, you should decide which you prefer better. However, I personally find 1. e4 to be a simpler opening to play, with less chances for blundering. Hope this helps!


After asking on the Discord as @Oscar Smith suggested in a comment, I got some results.

The person I asked said that you could download good weight files for Leela from this webpage: http://lczero.org/networks/

This was also said: "nT40.T8.610 (used in TCEC Sufi): https://www.dropbox.com/s/rmcf0lf1hes10gi/256x20.T8-swa-610000?dl=0 and currently in use in TCEC Rapid is 42547.pb.gz from above page. LCZero won Season 15 TCEC Superfinal  with above net T40.T8.610, but might not any more be strongest one."

I'm assuming that it's relavant to what you need.

Here is the Leela Chess Zero Discord link so you can find out more: https://discordapp.com/invite/pKujYxD


Can White win in this game (Q vs R+N+P)?

No, there is no chance for white to draw, let alone win, this game. In fact, if you enter this into an endgame tablebase it will tell you that it is mate in 13 moves with perfect play from both sides. One possible line is:

8/4K3/8/4Q3/8/4nk2/3p4/4r3 w - - 0 1

1. Qh5+ Ng4+ 2. Kd6 d1=Q+ 3. Qd5 Qxd5+ 4. Kxd5 Rd1+ 5. Kc5 Ke4 6. Kc6  Ne5+ 7. Kc5 Rd2 8. Kb5 Kd4 9. Kb6 Rb2+ 10. Kc7 Kd5 11. Kd8 Kd6 12. Kc8 Rb1 13. Kd8 Rb8++

Even if you don't have a tablebase, the position is quite obviously won for black. White's only hope in this position would be if he could capture the black pawn or if there was perpetual check. Neither of this is possible here, basically because all black pieces are working together and can protect each other and (and this is important), black is threatening a discovered check/pin which helps to prevent perpetual checks: basically if white checks with the queen black's knight can block the check, while at the same time giving check himself, thereby gaining a tempo for queening the pawn.

If you moved the white king away from this pin, it might very well be draw by perpetual check. For instance the same position with the white king on b8 is a draw.


It is not so much that Fischer got exiled as much as it was that he chose to exile himself (though yes, out of a certain necessity). He was indicted by a U.S. court for ignoring sanctions against Yugoslavia when playing his 1992 rematch against Spassky in that country, and so Fischer chose to avoid returning to the U.S. rather than face prosecution and a potential 10-year prison sentence. As to the various reasons he might have despised his home country, I won't speculate myself, but plenty has been written about Fischer's troubled later years elsewhere.


The closest one that I have found is called celestial strains at:
http://www.chess-museum.com/stone--glass-sets.html

There are some Polish sets on the site but they are not the same.


There's nothing special about this type of position. Play sound, solid chess. Activate your pieces, put your king into safety and occupy the center without overextending. You'll have an easier time than normal achieving an equalized middlegame


According to the FIDE rules,

  6.6 At the time determined for the start of the game White’s clock is started.

In over the board chess, it's usually Black who does this (you can't have an arbiter start all clocks simultaneously) after the players shake hands and wish each other good luck. If White isn't present, Black may start the clock anyway at the designated time; if Black isn't present, White should start his/her own clock, make a move and press their side of the clock to start Black's. (Of course, in some events, failing to show up at the designated start time constitutes an immediate loss anyway.)

So actually chess.com's method is closer to the official rules, though those games are of course not regulated by the FIDE rules.


Chess openings together with games played using this opening

Try TWIC, each week they release at least the top-rated FIDE games.

http://www.theweekinchess.com/twic


Question about knight vs. 3 pawns endgame


Is the Smith-Morra gambit still worth playing at a ~1600 level?

The gambit is perfect for amateurs, the gambit is tricky and could be deadly if Black underestimate White's attacking potential.

I've personally used it to beat players around FIDE 2000, so it's fine for you to try.


This is indeed an interesting position. I am assuming it is black to move because the highlighted knight move should be the last one, and also because otherwise black would lose their queen for no good reason.

It seems that white manages to get some compensation by forcing black to exchange their queen for a rook. However, the evaluation still favors black by a bit less than -2. Anyway, the ending looks very difficult to convert.

This analysis is according to Stockfish 9 at depth 22:

[FEN "r2q2k1/pp3Npp/1np1b3/2Q5/3r4/2N5/PP4PP/4RRK1 b Qq - 0 1"]
[Startply "0"]

1... Bxf7 2. Re7 Bc4 3. Qg5 g6 4. Qe5 Qxe7 5. Qxe7 Rd7 6. Qe1 Bxf1 7. Kxf1 Nd5


How to play against higher rated (much stronger) players

Unless you have gotten much stronger than your 1542 FIDE rating, you have to realize that your odds of winning are not very good. It is fine to be realistic, but just do not let that overwhelm your emotions.

You want to keep calm, and do not be afraid. I would not be afraid at all if I were playing Magnus Carlsen. Oh sure, I know what the result is likely to be as I am not crazy, but there is no point in having any fear, and I would just try to play the best chess I can.

It helps if you are white, but if possible, I would aim for a position where I can reasonably gambit a pawn, or two, for a wild tactical position. If you play a quiet position where your master opponent's stronger positional skill is not challenged, you are destined to lose. On the other hand, even low-level masters can make tactical errors, and over look something.

If you have a lot of time to prepare for him, like in a one-game-per-week tournament, go over every game of his you can get your hands on with a computer. It is not likely, but you might find some opening move that he has played that is a hidden blunder, and if so, you could aim for that position again.

Although rare, lightening does strike. Here is a game that I still recal reading during my first year of playing. This is from the 1980 U.S. Open, and a 1621 player, W Stanley Davis, beat GM John Fedorowicz, who was rated 2479 at the time, so good luck. Please note that it was an aggressive, tactical game.

This is from the December 1980 issue of Chess Life, and I took it from the free archives the USCF now puts out online.


Are aggressive attacking and tactical playeing the same?

They are related, but probably not the same. If you play an opening like the King's Indian you are probably an aggressive, attacking player, but you may rely more on the understanding of the position than on tactical tricks.
Similarly, there are certain types of position where accurate calculation is required but with defensive purposes.
Aggressive and attacking are probably harder to distinguish, though!


Did Aronian make a mistake in the opening against Anand in round 1 of the FIDE Candidates 2014?

Aronian played two sub-optimal moves in the middlegame - 16...Re7 and 18...h6. At each of these moves, the better move as per analysis by Houdini (depth 25 and above) was Nd5! (Houdini even prefers 17...Nd5, but 17...Rfe8 is not bad)

So his "mistake" was missing the opportunity to play Nd5, and instead playing 16...Re7 (which seems to be the major culprit) and 18...h6. If, instead, he had used the Nd5 idea, he could have equalized on move 16, and might have had better chances for equality if he had used it on move 18.

   [FEN "4rrk1/1bpq1ppp/p2b1n2/1p6/8/1B1P1N1P/PPP2PP1/R1BQR1K1 w - - 0 16"]

   1. Be3 Re7? (1... Nd5! 2. Bd2 c5=) 2. d4 Rfe8 (2... Nd5!? 3. Bd2 Nf4 4. Bxf4 Bxf4
   5.  a4+=) 3. c3 h6?! (3... Nd5! 4. Bd2 Rxe1+ 5. Nxe1 Nb6 6. Nc2+=) 4. Ne5! Bxe5
   5. dxe5 Rxe5 6. Qxd7 Nxd7 7. Red1+=

Explanation for 16...Nd5!

The idea behind 16. Be3 was to play 17. d4, which would strengthen White's position and prepare the Ne5 idea. Note that White couldn't play 16. d4 because of 16...Bxf3! The Ne5 idea gives White a pleasant edge in the endgame because of the two bishops. Therefore Black should have prevented it by preventing White's d4 move. Thus, the move c5 comes to mind, which discourages d4 because of c4, trapping the bishop on b3. However, c5 can wait for Nd5, an intermediate move, which forces White to retreat the bishop and also improves the position of the knight. After, Nd5 and c5, Black is completely equal.


Could I have some analysis by a player >2000 FIDE on this game?

I'm FIDE rated 2125.

So for your game, yes 10.Bxc7 would have been good for white.

As far as the opening goes, usually Nd2 happens with pawn c3 instead pawn c4.  If you want to do pawn c4 then the knight goes to c3 to put more pressure on d5.

Also, I would not play pawn to a4 like you did in the game.  It only causes b3 to be weak in my opinion.

But even though you eventually lose the pawn on b3, the position is tough to crack for black since there are no good pawn breaks to open the position for the bishops and the white knights have good outpost squares.

Overall, good effort!


I find out that my UCI protocol parsing had some nasty bugs, that's why all the Perft tests were ok, but the engine matches were buggy... ouch!

So it was not SCID's fault, sorry!


recommend a book on mid-game plan and board evaluation

"The Art of The Middle Game" by Keres and Kotov comes to mind.  And an older book,"Strategy and Tactics in Chess" by Max Euwe, was long considered a classic in this area. Of course study always has to be combined with practice.


Python-chess is_zeroing and is_capture operation outputs

The code for those routines fairly liberally uses bitwise-and (&) rather than boolean-and (and) for the logical expressions, so I assume integer values rather than booleans are being returned. I would guess that you would see something similar with is_castling if castling is possible; the False value is returned explicitly rather than being the result of an expression evaluation.


Importing and analysing games played on chess.com

I think chess.com has in-built Stockfish engine analysis, so I don't understand why you'd want to do that.

Don't like chess.com? lichess is easy. Just grab PGN of your game, import it into lichess. Select engine analysis.


Making sense of Scid vs. PC tree score statistics

The statistics show what happened in games that reached the current position.

So in your first diagram, there are 28 games that reached that position. White scored 30.3% on average in those games. In 11 of them, Nc3 was played here, and White scored 27.2% in those 11 games.

The position after Nc3 was reached 72 times. That obviously includes the 11 games from above, but also 61 other games that reached this position in a different order of moves. And in these 72 together, white scored 52.7%.

That's not inconsistent, you can go through the list of games yourself and verify the numbers.

What it is, is an example why looking at move statistics can be very misleading. The fact that white scored only 30.3% from the first position doesn't mean that black is winning at all. You don't even know that a single one of those results had anything to do with the opening! There could be all kinds of reasons for the results, maybe black was the much better player in all of them, or there were some white blunders, or who knows what.

Lies, damn lies, and statistics.


Tips for debugging and progressing a chess engine's implementation

I glanced at your code:

You should test your code with perft. Google it if you're not sure what it is.
Please make sure your code works before coding the engine search. If you unable to generate moves properly, nothing in your search will work.
Consider to use an array rather than a switch statement for piece values.
Consider to code your squares as an integer, not as a C++ class
Consider to collapse your WHITE and BLACK implementation together. C++ template would do that for you. Please take a look at Stockfish codebase if you're unsure.
I don't see you're making en passant in the code. Are you sure you have that covered?


Effectiveness of a spaced repetition system (SRS) for memorizing tactical patterns for long-term skill gain?

It is just anecdotal, and correlation is not the same as causation, but a few years ago I started using the Mnemosyne spaced repetition program to memorize

Opening lines (a few thousand cards here alone)
Positions from

Yusupov, Build Up Your Chess et al
Hellsten, Mastering Chess Strategy
Ivashchenko, Manual of Chess Combinations
Rosen, Chess Endgame Training
My own games where I had made a bad decision

During this time, my USCF rating, which had never moved much as an adult, went from under 1800 to over 2000.


How to save/open games on Stockfish for Mac

I don't own a Mac, so I can't test these myself (and the solutions' efficacy might vary with software/firmware), but here are some solutions that have worked for others:

Per ref. 1:

Note: Invalid moves in the PGN file seem to prevent the file's opening.
At the end of every line in the PGN file, add a space. Then they should open with the current version of Stockfish for Mac.
Open the PGN files with a text editor and convert the line endings to CRLF (Windows line endings). Then they should open with the current version of Stockfish for Mac.
Compile and run the latest Stockfish for Mac development version from GitHub. This has the fix.

Per ref. 2:

If you're playing a chess variant, then add a FEN tag to the PGN file (if there isn't one there already).

FEN tag example:

  OTHER TAGS GO HERE
  [FEN "brkbqnrn/pppppppp/8/8/8/8/PPPPPPPP/BRKBQNRN w KQkq"]
  [SetUp "1"]

  MOVES GO HERE

References:

http://support.stockfishchess.org/discussions/problems/3362-pgn-files-not-opening-stockfish-for-mac
https://www.reddit.com/r/chess/comments/2w9zgf/how_do_i_use_stockfish_with_chess960/


Why isn't chess played with flat pieces?

It's probably for historic reasons. Chess is very old and a metaphor for two armies making war, and people chose to make 'statues' to represent the pieces. Since this has worked well so far, nobody felt the urge to change them to 'tiles', that is, until computer chess came into being. I've never played Shogi on a real board, but I can imagine 2D pieces are harder to grab than 3D pieces. At least, that is my experience with playing draughts; with moves, you can push a piece, but with captures you have to pick up a piece.

But why is Shogi, which also has a rich history, played with tiles? Well, one good reason might be promotions:

They are much more common than in chess
A piece promotes to a predefined other piece (there is no choice like in chess)
In case it's captured, it matters what the original piece was

Flipping a tile is an elegant solution for this problem, unlike replacing it with another piece from outside the game.


How to deal with your opponent's queen if your opponent rejects any trades?

There is no need for an early queen trade. Just develop your pieces, if possible by attacking the queen. Here is an example from the Wayward Queen Attack also known as Patzer Opening.

[fen ""]

1. e4 e5 2. Qh5 Nc6 3. Bc4 g6 4. Qf3 Nf6 5. Ne2 Bg7 6. Nbc3 O-O 7. d3 d6

2.Qh5 threatens to take e5, so we defend it by developing a piece: Nc6 (d6 is also possible).
3.Bc4 threatens to mate on f7, so we defend it by attacking the queen with g6, creating a square for our bishop as a side effect.
4.Qf3 renews the threat, so we develop another piece, Nf6 and block the queen's access to f7.
Then we develop our bishop, castle and get a nice game with a development advantage.

The best punishment for an early queen development is not a queen trade, but using this queen to develop your minor pieces with a tempo: by forcing the queen to move again and again.

Update

In the example you gave in the comment, you play just the same way: Develop your other knight, get castling in, and have a good game. There is a reason why you don't see this line in games by players with a decent rating.

[fen ""]

1. e4 c6 2. Nf3 Qa5 3. Nc3 d5 4. Be2 dxe4 5. Nxe4 Bf5 6. Ng3 Bg6 7. O-O Nd7 8. d4

First let me say that 2.Nf3 is not the best move against the Caro-Kann. d4, Nc3 or even c4 are better and therefore more common. See my Caro-Kann study for more ideas.

After 2…Qa5 you just play Nc3 which develops a piece and unpins the d-pawn. Then you clear the f1 square by developing yet another piece, Be2, castle as soon as possible, and then play d4.
Black is at this point seriously behind in development: the entire kingside is still in the default position while you have already some very annoying moves like Nh4,  c4, or Bf4. Your queen on d1 is keeping everything together. It's not in the way of any other piece and much better than Black's queen – and you didn't even move it!

So, again: stay calm, develop your pieces, castle, and then question your opponent's position with your own minor pieces.


TL;DR: In summary, the sources I've found of the match reference Fischer himself.

Fischer sent the game scores himself:

  Rumors constantly reappear about the possibility of his playing again or making public appearances, but the only published games that we know of since 1972 were against the Greenblatt program, and they were submitted by Bobby himself and published in the Computer Chess Newsletter. Bobby sent the scores of three games in which he massacred the computer. In his comments on the games, Bobby noted that the computer was very weak and that he could give it great odds and still beat it.

Source: csmonitor.com

The match was held in Cambridge, MA:

  In 1977, unbeaten chess champion Bobby Fischer played three games in Cambridge, Massachusetts against Greenblatt's computer program, and Fischer won all of them

Source: Wikipedia, referencing Bobby Fischer's biography

I haven't found contemporary images or information on how the match was arranged.


Winning Chess Strategy for Kids by Coakley is EXACTLY what you want.

Barely a few pages explaining basics. Then tons of practical content that even adults will find useful.   Wastes no time in getting intermediate lessons in strategy/tactics presented in an astonishingly kid-friendly way. :)


Can someone explain how this pawn endgame works?

I think considering an intermediate position first helps clarify what is going on. Consider the following position with Black to move. The white king is on d4, poised to head for infiltration on either the queenside or the kingside. The only drawing move for Black is to play 1...Kd8!, not committing to one side or the other. (For instance, 1...Ke7? reaches a position from the OP's main line, where White wins by heading to the other side via c3.) Playing through the variations and annotations below from this position will (hopefully) show how the opposition and distant opposition come into play rather immediately from this point.

[White "Intermediate"]
[Black "Position"]
[FEN "8/3k4/3p4/3P4/2PK4/8/8/8 b - - 0 1"]
[StartFlipped "0"]

1...Kd8 $1
    {This is the only drawing move. When the white king comes to d4, so
    long as the black king can play to d7 or d8, the game is still drawn.
    But if the black king has to commit to one side or the other (to the
    c-file or e-file) then the white king will be able to infiltrate on
    the other side.}
    ( 1...Ke7 $2 {This reaches a position from the OP's main line, where
    now White can infiltrate from the queenside.} 2.Kc3 $1 Kd7 3.Kb4 Kc7
    4.Ka5 $1 {Not giving Black the chance to steal back the opposition.}
        ( 4.Kb5 $2 Kb7 )
    )
    ( 1...Kc7 $2 {Going this direction lets White invade on the kingside.}
    2.Ke4 Kd8
        ( 2...Kb6 $5 {White must keep in mind this counterattacking idea,
        but it doesn't work out.} 3.Kf5 Kc5 4.Ke6 {White wins via the
        classic trebuchet.} )
    3.Kf5 Ke7 4.Kg6 Ke8 5.Kf6 Kd7 6.Kf7 Kd8 7.Ke6 Kc7 8.Ke7 )
2.Kc3
    ( 2.Ke4 Ke7 3.Kf5
        ( 3.Kf4 Kf6 )
    3...Kf7 {Black maintains the peace.} )
2...Kc7 3.Kb4
    ( 3.Kb3 Kb7 $1 {Again the only drawing move. Without maintaining the
    distant opposition, White can infiltrate.} )
3...Kb6
    {Black maintains the peace.}

Returning to the starting position, then, if White can maneuver his king to d4 in such a way that Black cannot play her king to the d-file in response, he will have a won game. What needs to be done to achieve that? White needs to force matters such that Black must either (1) allow the intermediate position where she can't get to the d-file, or (2) get outflanked and allow infiltration anyway. Use of the distant opposition is the only way for White to force such a decision onto Black; what complicates matters is that the mass of central pawns take squares away from each king, and that affects when one "really" has the (distant) opposition or not. The following variations and annotations attempt to show how this plays out, and to give a sense as to what considerations come into play. Certainly not every possible variation is given, but hopefully just enough wrong turns are explained to show what is going on.

[White "Starting"]
[Black "Position"]
[FEN "8/4k3/3p4/3P4/2P5/8/8/5K2 w - - 0 1"]

1.Kg2 $1
    {This, and only this, gives Black no way to grab the distant
    opposition. Whatever move is made now, White will be able to force an
    untenable decision onto Black.}
    ( 1.Kf2 $2 Kf6 $1 {Maintaining the distant opposition keeps the
    balance.}
        ( 1...Kf7 $2 2.Kf3 $1 {Stealing away the distant opposition, the
        only winning move.} 2...Kf6 3.Kf4 $1 {Keeping the opposition. Now
        Black has a choice. Either allow the White king to infiltrate
        along the outside of the kingside, or try to force the white king
        toward the center. The latter is more stubborn, but we end up in
        the intermediate position from above where the black king is
        overcommitted and cannot get to the d-file after Kd4.} 3...Ke7
            ( 3...Kg6 {Now on the g-file, there is no time to get back to
            the d-file when the white king heads to d4.} 4.Ke4 Kf6 5.Kd4
            Ke7 {Now we are in the OP's main line, and also the
            intermediate position where black has had to commit to the
            kingside and allow infiltration on the queenside.} )
        4.Kg5 Kf7 5.Kf5 Ke7 6.Kg6 Ke8 7.Kf6 Kd7 8.Kf7 Kd8 9.Ke6 Kc7 10.Ke7
        )
    2.Ke3 Ke7 $1 {Keeping the distant opposition, and not falling for an
    appealing alternative.}
        ( 2...Ke5 $2 {This looks like taking the opposition, but because
        d5 is unavailable, this is just a mistake.} 3.Kd3 $1 Kf6 4.Kc3 {
        Black won't be in time to keep White out of the queenside.} )
    3.Kd4 Kd7 $1 {Kd8 works as well. This is our intermediate position
    where Black just needs to be on the d-file.} )
    ( 1.Ke2 $2 {This also lets Black get the distant opposition.} 1...Ke8
    $1 {The only drawing move, taking the distant opposition.} 2.Kf3
        ( 2.Ke3 Ke7 $1 3.Kf3
            ( 3.Kf4 Kf6 )
            ( 3.Kd4 Kd7 {Safely on the d-file.} )
        3...Kf7 $1 )
    2...Kf7 $1 3.Ke4 Ke8 4.Kd4 Kd7 {Safely on the d-file.} )
1...Kf6 2.Kf2 $1
    {Only this, taking the distant opposition.}
2...Ke7
    ( 2...Ke5 3.Ke3 $1 Kf6 4.Kd4 Ke7 {The intermediate position, where
    Black hasn't stayed on the d-file.} )
    ( 2...Kf5 3.Kf3 Kf6 4.Kf4 {This is the same position as after 1.Kf2?
    Kf7? 2.Kf3! Kf6 3.Kf4 given in another variation. Either Black gets
    outflanked on the kingside, or allows the intermediate position
    unfavorable.} )
3.Kg3 $1
    {Starting to outflank, and doing so in such a way that Black cannot
    grab the distant opposition. Only this wins.}
    ( 3.Ke3 $2 {This looks like grabbing the distant opposition, but it
    cannot be maintained because of squares made unavailable by pawns. Now
    the game is drawn.} 3...Ke8 $1 {Only this. It prevents an unfavorable
    instance of the intermediate position, and allows Black to grab the
    distant opposition should White head toward the kingside.} 4.Kd4
        ( 4.Kf4
            ( 4.Kf3 Kf7 $1 )
        4...Kf8 $1 )
    4...Kd7 {Safely on the d-file.} )
3...Ke8
    ( 3...Kf6
        ( 3...Kf7 4.Kf3 $1 )
    4.Kf4 $1 )
4.Kg4 $1
    {Again not allowing Black to grab the distant opposition, and only
    this wins.}
4...Kf8 5.Kf4 $1
    {Only this.}
5...Kg8
    {Now that the black king is on the g-file, White can head for Kd4 and
    the intermediate position where the black king can't get back to the
    d-file.}
    ( 5...Ke7 6.Kg5 {Infiltrating as in other variations given.} 6...Kf7
    7.Kf5 Ke7 8.Kg6 Ke8 9.Kf6 Kd7 10.Kf7 Kd8 11.Ke6 Kc7 12.Ke7 )
6.Ke4 Kf7 7.Kd4 Ke7
    {White wins as in the OP's main line.}


A case where Bishop for knight isn't a good trade

it's a bishop for knight in my favor

So what? You will have moved the knight 3 times to your opponent's bishop 1 move and you will have improved your opponent's position by opening the f file for him. So, not in your favour after all.

  the bishop makes my position slightly vulnerable because of the pin on the queen

No, it doesn't. If it ever becomes a threat you can nullify it with NxB. Until it becomes a threat you are reacting to a phantom.

  the knight outpost is appealing but it can be kicked with c5

To which you can react with NxB! Again, you are reacting to a phantom. Although Ndb5 would be much better increasing the pressure on the backward and now weak pawn on d6.

The reason you won the game is that your opponent blundered. His reply to your Rad1 of moving the knight back to f6 for no good reason was terrible. Far better would have been to kick your bishop with e5. With the knight on g4 protecting e5 this is possible and very good. With the knight back on f6 this is not possible.

As is often the case the move you chose, NxB, releases tension unnecessarily, and in this case in your opponent's favour. Playing Rad1 retains the possibility of NxB if it looks better later and it reinforces the center and places a rook opposite black's queen. It is just a much better move.


CHESS PROBLEMS MADE EASY - How to solve, how to compose
How to compose chess problems and why (You have to register for free to read it)
Chess Wizardry: The New ABC of Chess Problems
Compose Like Mozart
What are chess problems

Additional links

Chess Problems
The Chess Portal: Chess theory/Chess Problems (that list has many recourses on Chess composition)


Why was the engine giving such positive evaluations for my game with equal material?

on move 22 Stockfish 12 gives me +7 at depth 22 being only one pawn up
even though black's pieces are out

Black's pieces are not all out and the ones that are aren't on the right squares. Black is still several moves away from being able to castle safely. Meanwhile you have completed development, including the queenside castling safety move Kb2, and some of your pieces are on very good squares.

how can I consistently/intentionally play like this?

The best move you made was picking a patzer for an opponent, someone who develops two pieces and then starts a wild attack making pointless wing pawn moves. The next best thing you did was obey standard opening principles of developing your pieces properly. Continue doing those two things, particularly the first, and you should win all your future games.


UCI2WB which you can find it in Winboard packages.

PolyGlot is another option.

Many modern chess GUIs doesn't need external converter such as ChessX, Fritz, ...


Anand - Carlsen Game 1 WCh 2014, why not 12.Qc3+?

[FEN ""]
                [Event "WCh 2014"]
                [Site "Sochi RUS"]
                [Date "2014.11.08"]
                [Round "1"]
                [White "Anand, Viswanathan"]
                [Black "Carlsen, Magnus"]
                [Result "1/2-1/2"]
                [Eventdate "2014.11.08"]

                1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.cxd5 Nxd5 5.Bd2 Bg7 6.e4 Nxc3 7.Bxc3 O-O 8.Qd2 Nc6 9.Nf3 Bg4 10.d5 Bxf3 11.Bxg7 Kxg7 12.Qc3+ e5 (13.dxc6 Be4 14. Qe5 f6 15. Qc3 Re8 16. Be2 Bxc6)
    (13.gxf3 Nd4 )
   (13.Qxf3 Nd4 )
   (13.dxe6 Qf6 14. Qxf6 Kxf6 15. gxf3 fxe6)

Computer Houdini 1.5a w32 suggests 13... e5
Now four options for white 13.dc 13.de ep, 13.gf or 13.Qf3 anything else loses a piece.

After 13. dc black replies 13... Be4 and white cannot take pawn on e5. If 14. Qe5 then 14... f6 15. Qc3 (15 Qe4 loses a queen). 15... Re8 this forces white reply  16. Be2 and black just takes on c6 16.... Bc6 , this is a win for black.

13.gxf6 black moves its knight to the centre 13... Nd4 Knight on d4 cannot be moved. Pawn on f3 is weak. Black is better.

13.Qf3 Again same idea – black’s knight occupies the centre Nd4 and whatever white answer is black threatens to crush the white centre 14... c6. Again black is better (maybe not as good as after 13. gf)

13.dxe6 e.p. black needs to cover the diagonal – 13... Qf6 or 13... Qd4 anything else consolidates white’s position in the centre.
13...Qf6 14 Qf6 (otherwise black takes on c3) 14... Kf6 (forced) 15 gf (forced) 15... fe again black is better (weakness on f3)
13...Qd4 white cannot take on d4, so 14. e7 (if 14. gf black takes on c3 and again weakness on f3 is giving black an advantage)  14... Re8 15. gf again cannot take on d4. And now either 15...Re7 or 15... Qc3 and black has better pawn structure.


Looking for a chess variant with a circular board

A few suggestions:

This looks sufficiently circular and weird, though I didn't find the rules.

For three people.

And there is apparently a circular citadel chess, with triangles in the middle.


What is the origin of this breakthrough combination?

I just saw it in one of Yusupov's books, he has it credited as "Cozio 1766".

His 1766 book "Il Giuoco Degli Scacchi" is actually digitized by Google books: http://books.google.it/books?id=aCcCAAAAYAAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=thumbnail&q&f=false

Unfortunately, neither diagrams nor notation were invented yet. You're on your own to find out where he describes the position...


What is the most amazing chess position you have seen?

And one last one from a real game. Black to move and win.

 [Date "2003.??.??"]
 [White "Ibrahim"]
 [Black "Ibarra"]
 [FEN "3q4/1p1n1pk1/p1r1p1p1/2P1Pn1p/1P1N1P2/B5rP/5RPK/Q3R3 b - - 0 1"]

 1... Nxd4 $1 2. Kxg3 (2. Qxd4 Rxa3 3. Rd1 Qh4 {is just up a piece.}) 2... Qh4+ $3 3. Kxh4 Nf5+ 4. Kg5 Nf8 5. g4 {and there is no defense to....} Nh7#


Because that would move the king into check - the queen is defended by the bishop on c5.

More generally there is no problem with a king taking a piece that is checking it, provided the capture does not move the king into check or break any of the other laws of chess.


Magnetic chess sets have a metallic board and small magnets in each of the pieces.


Is this KBPP vs. KR position a draw or a win with perfect play?

IF White wanted to have any winning chances, the pawns should either be connected or, at least, staying in dark squares for quite some time. In the presented position, even if the central pawn pushes, Black will be able to blockade in the second rank


INTRODUCTION AND RELEVANT INFORMATION:

  I am a beginner in chess and don't understand the concept of openings
  at all. To me they appear to be just moving one of the eight pawns or
  one of the two knights.

This is the root of the problem, and the reason why you have asked the question-it is the consequence of your ignorance.

POINT #1:

You must understand that human being plays the game, and human beings have likes and dislikes. Some of us prefer sharp and fast struggle, and some of us like slow and safe maneuvering, and so on...

POINT #2:

You do not appreciate your turn to move, but in chess, this is very important to master.
You see, when it is your turn to move, you have a choice, and this is really important.
This is the moment where you have a say, and you can change the course of the game to your like ( see the POINT #1 ).

This is one of many things that differentiates master from novice-master enforces the pace of the game, while beginner complies/plays any move without careful thinking, which results in him/her lamenting later " How did I get into such a horrible position??? How did I blundered a bishop?? " and so on. In chess, this is called tempo.

You must comprehend that you too are the factor in the game, and that this is collision of characters.You must comprehend that not only you play "against pieces" you play against another human being.

Your approach to the game is faulty, because you " dissect " the game, and probably in your opinion there are 3 parts of the game:

Opening
Middlegame
Endgame

This type of division is old and inefficient.

In order to understand my answer, and other answers provided from different members, you must change the approach.

You open the game in order to develop pieces the best way to carry out your middlegame plan, and your middlegame plan is based on the possible events that might take place in the endgame ( chess rules can help you in this, serving as a beacon to follow, but true mastery comes when you learn when to break them-that comes with experience ) .

This is the approach that is the most efficient, in my opinion.

ANSWER:

  What is the significance of openings?

Openings help you to determine what type of opponent is playing against you-does he/she like fast, open battle, or slow and maneuvering one, does he/she aim for endgame or mating attack and so on...

Opening allows you to choose how to tackle those opponents, and enforce them your style of play.

A small example:

Let us say your opponent opened with 1.e4 and you do not want open battle.Let us assume that you like slow maneuvering battle, and feel comfortable playing endgames. In that case you would like to answer with a move that doesn't force early conflict but allows you to choose the moment when the big battle will take place. You could play 1. ...c6 and be confident that the further development of events will be suitable to you.

But what if you want the opposite? What if you want a fast, sharp, open battle?
Then you could reply with 1. ...Nf6 for example. Notice the change of the rhythm:
In the first example White had a choice after Black's 1st move, but now is forced to play with the e-pawn or to defend it.This small example fantastically illustrates POINT#2 from the introduction ( in fact, the whole opening does, and is called Alekhine's defence ).

In open positions, you do not get static solidity and you have to adapt to the changes in the position "on the fly".
In closed ones, your position is solid but you usually need a lot of effort to generate counterplay.

To resume:
Opening helps you to reach the positions that suit your stile ( style being your character/skill level... ) and their knowledge helps you to prepare the position to transpose into middlegame that also corresponds to your style, as well.
Knowing the opening means that you will not be defeated in first 10 to 25 moves, and gives you certainty that you will have an enjoyable game with equal chances to win.

  What is the need to differentiate them with so many names, for after all as I mentioned earlier, it is going to be one of the eight pawns or one of the two knights?

The classification of the openings allows you to find the opening you wish to study, and the openings you wish to prepare against.

These are generally classified as follows:
A ( unsorted ), B ( semi-open games ), C ( open-games ), D ( closed games ), E ( semi-closed games ).

There is an overwhelming amount of moves/move orders and so on, to study and so many openings with the same general idea, but different implementation so you might want to look at them all and choose the one that suits you the best.

Another small example to illustrate this:
Let us say that you are slow, endgame oriented player.
You need an opening that gives you solidity in the beginning, and an advantage in the endgame.
Let us say that you want to prepare against 1.e4.
You could choose 1. ...c6 or 1. ...e6, but although they have the same concept ( repel White's initiative and smash him in the endgame ), there are differences:
The first choice offers harder time to generate counter play, but you have no weak pieces, yet the other one generates counter play easily at the expense of the weak piece ( the light squared bishop ).
Two openings with the same idea, but the implementation of it is drastically different,and only one of them will suit to you.
After you pick one of them, another question arises: Which particular variation in that opening suits your style?
Now comes the strength of POINT #2 into play!
Let us say you have picked 1. ...e6, and let us start "studying" it for a while:
1. e4 e6
2. d4 d5
3. Nc3

A "sharp, fast paced, open battle" player would choose 3. ...Bb4 here forcing the matters, while the slow, solid one could try with 3. ...dxe4, for example, simplifying and slowing things down a bit.

Let us assume that you decided that the second option suits your style and you wish to study that.

But how will you find material for this opening?

Well, first you search the name of the opening-it is French defense.
Then you search its general code-it is C.
Then you search the variation you are interested in-it is 10.
So the opening code is C10.
And now you can find online materials/books on the opening you want to play.

Sorry for the lengthy post, hopefully it will help you.
If you have further questions ask, and I shall answer them as soon as I can.
Best regards.


Does your rating express the quality of your play regardless of time control?

The way ratings are mathematically defined, they don't express the absolute strength of players, but only the strength of players in a pool relative to each other. So there is no meaning in trying to compare blitz rating and standard rating, the way you are trying to suggest.

For the same reason you cannot compare computer ratings with human ratings, because they are calculated from different pools: computers playing only against computers vs humans playing only against humans.

Also for the same reason you cannot really compare ratings on different websites or online ratings with FIDE ratings.

That being said, most of the good players (above say 2600 in standard) are also decent Blitz players and would have a comparable blitz rating.

Still, speaking of absolute strengths, their blitz games would (on average) be worse quality than their standard games.

Giving a concrete example: Ding Liren and Hikaru Nakamura both have blitz and standard ratings in the 2800. So they are equal in strength in blitz (compared to each other) and in standard, but that is because they are equally worse in blitz....


Chess originated in India and in the Indian armies of those times, it was common to have elephants, camels, horses and the like. Even now in rural India, the rook is the "elephant", the bishop is the "camel" and the knight is the "horse". The king is still the king, the queen is the "wazir" or vizier, and pawns are foot soldiers. In fact there was a recent Indian movie called Wazir, themed on chess and the Wazir was portrayed by a male character.

Traditionally, the armies fought mostly with men, however, even Indian history has had female warrior queens (for example Rani of Jhansi). The Wazir, however, is not a queen, but a powerful minister in the kingdom, maybe even the king's prime minister or right-hand-man (person?). Traditionally, this would be a male. Similarly, the elephant riders, camel riders, horse riders and foot soldiers would traditionally be male with females being the exception to the norm. The king is obviously male.


Python-chess : how to get a list for the best engine moves

As per: https://python-chess.readthedocs.io/en/latest/engine.html#indefinite-or-infinite-analysis

engine.analysis(board) now returns an AnalysisResult object, which has the property info that you want.

So instead of:

nwinfo = engine.analysis(...)
print(nwinfo["score"])

You would loop over info in the AnalysisResult, and print the score property from each element:

with engine.analysis(...) as analysis:
    for info in analysis:
        print(info.get("score"))

However, your use case looks like it may benefit from engine.analyse more than engine.analysis.


Gameknot allows mini-tournaments to specify a starting position for all games in the tournament. This is a popular way to explore openings; I do it frequently.

Mini-tournament participation does require that you've completed a few games on the site already though.


Shortest game controlling a single square 16 times?

Addendum #2: It turns out that a move can actually be saved further still! Michel Caillaud wrote on the Retro Mailing List that 19.5 moves is possible!
[Title "Michel Caillaud, Retro Mailing List 9/18/2020, Non-unique Proof Game in 19.5 moves"]
[FEN ""]
[startply "39"]

1. f4 h5 2. f5 h4 3. f6 h3 4. fxe7 hxg2 5. exf8=N Rh6 6. Nh7 a5 7. Nc3 a4 8. e4 a3 9. e5 axb2 10. e6 b1=N 11. e7 Nxd2 12. Nh3 Ne4 13. Nf2 f6 14. Ng4 Kf7 15. Qxd7 Ra6 16. Qd4 Nd7 17. e8=N gxf1=N 18. Nd5 Nfg3 19. Bg5 Nh5 20. Rf1

Addendum #1 After some back and forth emailing on The Retro Mailing List last night, Eric Angelini has devised a much shorter game than mine in 20.5 moves! This is surely optimal. Good job Eric!
[Title "Eric Angelini, Retro Mailing List 9/18/2020, Non-unique Proof Game in 20.5 moves"]
[FEN ""]
[startply "41"]

1. a4 d5 2. a5 d4 3. a6 d3 4. axb7 dxc2 5. bxc8=N cxd1=N 6. Nb6 Nf6 7. Na4 Ne4 8. h4 f5 9. h5 f4 10. h6 f3 11. hxg7 fxg2 12. Nf3 g1=N 13. g8=N Nxe2 14. Nxe7 Na6 15. Nd5 Nb4 16. Ra3 Na2 17. Rxh7 Qf6 18. Rxc7 Rh3 19. Rc2 Bb4 20. Nd4 Rc8 21. Nb5

For starters, there are a limited number of squares that can be attacked 16 times. A square can only be attacked eight times horizontally and vertically, or four times from each direction. The other eight attacks are from one knight each. A knight can only have its full reach on the central sixteen squares. Therefore, we are restricted to those squares only.
Furthermore, while we have plenty of horizontal and vertical moving pieces in the initial game array, only four knights are present. This means that four more knights must be promoted. The shortest way to do this, theoretically, is to promote 2 knights for both White and Black to split the workload. Promoting four knights already puts us at least 10+ moves in total in addition to the knights' moves to their attacking squares.
Here is my beginning bid of 25.5 moves with the target square of d6.
[FEN ""]
[startply "51"]

1. d4 e5 2. dxe5 d6 3. a4 b5 4. b4 a5 5. axb5 c5 6. Na3 c4 7. Nxc4 Ra6 8. bxa5 Rc6 9. b6 Nd7 10. b7 Nc5 11. a6 h5 12. a7 h4 13. a8=N h3 14. bxc8=N Nb7 15. Nc7+ Kd7 16. Nb5 Qc7 17. Ba3 hxg2 18. h4 Rh6 19. h5 Re6 20. h6 Nf6 21. h7 Ne8 22. h8=N gxf1=N 23. Nxf7 Nd2 24. Nf3 Ne4 25. Nh4 Be7 26. Nf5


Concerning a chess problem generating program

AFAIK, there aren't programs that generate chess problems On the other hand, there are several well known programs to verify chess problems (even with fairy chess conditions).
The main reason is that composing a good problem is kind of an art, the problem should not only be valid (in the sense that it is solvable etc.) but also esthetically pleasing. It also should be original, showing something new or fresh. These aspects are badly handled by computer programs upto now.


What are the differences between tactical and positional chess?

I don't think one style has an advantage, or at the GM level, there would only be one style; the other would be extinct.

The very definition of a tactical player is Mikhail Tal AKA 'The Wizard of Riga.'  Others include Bobby Fischer and Garry Kasparov.  Anatoly Karpov and Tigran Petrosian are great examples of positional players.

Fischer himself said that tactics flow from a superior position.

Edit: I'd like to add that any of the top players can find the best move in a given situation. Where positional versus tactical considerations come into play is where there isn't a best move, as such.  That is, when there are several reasonable candidate moves.  Then some players show a positional tendency while others show a tactical tendency.  Petrosian, who is probably the most defensive GM, was more than able to uncork technical savagery if his opponent let him.  However, he preferred to tighten the noose instead of looking for a brilliancy.


How to decide whether to exchange (good/active) bishops

This position is from an early stage of a 960 game where the pawn position has not yet stabilized and it has little in common with the London system. Both sides will probably need to move some more pawns to get their pieces out, since particularly the Rooks and Knights are clumsily placed. A plan for either player must be comprehensive, taking account of all the pieces, and could go in many directions, depending in part on what the opponent decides to do. At this stage of the game it would be a mistake to focus too narrowly on the Bishops
In the London system, White aims at establishing a slight advantage in space, giving him more freedom than Black to manoeuvre. Any exchange of pieces will ease that aspect of .Blacks problem, and often this is accomplished by playing ...d5,..e6, and ..Bd6.
The downside (There is usually a downside) is that Black will be left with a light-square Bishop that is somewhat restricted by its own Pawns.
A situation often arises in the London system where the Bishops are on d6 and g3. In that situation Black usually should not exchange if he has already castled short and Whites Rook is still on h1. So the decision can depend on much more than the relative merits of the Bishops.


Cases of grandmasters renouncing titles, tournament victories, etc?

I have been playing tournaments for 39 years, 34 as a USCF Master, so I follow chess closely; but other than Fischer, I have never heard of anyone doing it voluntarily DURING their reign. Alekhine is the only other male World Champion not to defend his title, but did it involuntarily (he died). :)

Other cases of not defending their title include Hou Yifan, who decided not to defend her Women's World Championship title in 2015 due to another commitment, and after winning it back in 2016, again she chose not to defend in 2017 protesting the knockout system (I do not blame her).

Of course, some have not defended their lesser titles for various reasons, like political and moral. Anna Muzychuk refused to defend her world titles in rapid chess and blitz in 2017 due to Saudi Arabia’s treatment of women.

I have heard of a few, who were stripped of their titles like GM Gaioz Nigalidze for computer cheating (demoted to IM). GM Igors Rausis is most likely facing the same sanctions for his recent cheating incident (He admitted it, and announced his retirement).


My rook was targeting the opponent's king but her knight was in between

This is what is called an (absolute) pin in chess, i.e. the knight is pinned by the rook and cannot move, because it would put the king in check (which is not allowed).

  I moved my knight to the check place checked by same knight

The way I understand it, what you mean is something like: I moved my knight to a square attacked by the pinned knight. Of course this is perfectly legal as there are no restrictions put on the movement of your knight.

  Can I move my king to that place

No, you cannot move your king to a square attacked by an enemy piece, even if the piece is pinned.

If you think of "winning in chess" as "who captures the enemy king first", all of this makes sense. Specifically, the pinned knight would move first to capture your king, just before you could capture her king (which is now under attack since the knight has moved).

If you search a bit on stackexchange you will find many questions regarding this problem, such as: this question.


Why is this position considered to give white a significant advantage?

[FEN "r4rk1/2p1qppp/1p3n2/p7/2B4B/4P3/PPQN1Pbb/2KRR3 w - - 0 1"]

1. f3 {traps the bishop} Rad8 2. Re2 Bxf3 (2...Bd6 Rxg2 Kh8 Rh1 {the Black king is not safe at all}) 3. Bxf6 Qxf6 (3...gxf6 Rxh2 {checkmate on h7 will follow}) 4. Rxh2 {threatening mate on h7} h6
5. Rf1 {the bishop is now pinned against the queen and will be won shortly} b5 6. Be2

f3 followed by Re2 wins a bishop (Re2 Bc6 f4 wins the other one), and with no pawns on the h- and g-files it will become evident that the Black king is not safe at all. This solution is simple enough to gain a significant advantage (+2). But there is an even more brutal sequence that wins both bishops with some finesse.


According to the Chessfiles [ref. 1], Arena [ref. 2] can be played on OS X within Wine 1.0 or higher [ref. 3]. Likewise, Arena claims to function within Wine 1.0 or higher.

Caveat: some indicate Arena to be unstable within Wine [ref. 4], some have no problem [ref. 5, 6].

References:

http://www.chessfiles.com/os-x-chess-gui.html
http://www.playwitharena.com/
https://wiki.winehq.org/MacOSX
http://www.open-aurec.com/wbforum/viewtopic.php?f=2&t=6550
http://ubuntuforums.org/archive/index.php/t-377613.html
http://ubuntuforums.org/showthread.php?t=31659


The exact rules aren't known, but what is known or commonly believed to be true is listed on Wikipedia. Especially the elephant/gaja's movement rules are uncertain.
It varies from modern chess because it has some pieces which move differently: the elephant mentioned above and the mantri/minister. Modern chess has the bishop and queen in their places. Still, the complexity of the game is comparable to chess, so it's a long way from being solved.


There are two main categories for motifs in chess. Those are strategic and tactical motifs. Beginners should should focus on tactical motifs because strategic advantages are much smaller and negligible compared to material advantage, which tactics are usually the cause of.
chesstempo has a good list of these.

http://chesstempo.com/tactical-motifs.html


Free online analysis board between two players (both players can move the board)

Lichess.org has a feature called studies. You can add your game as a chapter in a study, invite your friends as contributors and make that study public or private. You have a (rather weak) engine analysis, a small database of chess games, and a chat. You can annotate your game, add alternative lines and so on.
The multi-chapter option makes that very useful for much more than game analysis. I'm using it primarily for opening studies.

Here is a screenshot from my Caro-Kann study:

Not free, but also worth a mention: Chess24.com has an analysis board for premium members. Very similar features, but there is only one game per analysis, not multiple chapters. The database is better (larger and properly cleaned up names, lichess is sometimes a bit annoying in that regard). You have to start a broadcast (see screenshot), and then you can invite your friend who doesn't need a premium membership for that. The downside is that the chat vanishes once you stop the broadcast.

In both cases you can move pieces on the board, and all other participants can see and annotate these moves.


Does the new Netflix series "The Queen's Gambit" resemble any real life chess master?

The character Beth Harmon is purely fictional. The series is based off a book by the same title by Walter Tevis. The author had a tendencie to base books drawing from personal experiences but he wasn't a chess prodigy that's for sure. He was however a good club level player which is why the book has such strong chess knowledge. In that time period, there are no valid players that could fit as inspiration for the character (that I can place at least). The chess advisors in the show were Bruce Pandolfini and Garry Kasparov which really shows the high-calibre efforts the production team went to to get the show's chess moments bang on.
EDIT: Found the following article
https://www.radiotimes.com/news/on-demand/2020-10-29/the-queens-gambit-book-netflix/

Tevis previously told The Times that the character was created as a
“tribute to brainy women” adding that “I like Beth for her bravery and
intelligence. In the past, many women have had to hide their brains,
but not today,” he said.
He listed his daughter and his aunt – who had gifted him with his first chess set – among the women who had inspired the character.

Regarding the games however that is a different story; Most the games are based on famous games.  The final game in the series where she beats Borgov is based off a game between Vassily Ivanchuk and Patrick Wolff at the Biel Interzonal in 1993 for example. An absolute monster of a game to watch though;
Those researching the film did a fantastic job in finding great games to base their games on. Specifically move 38 Ne6 which is a more direct and simplified line.
The Movie Game (Simplified Ivanchuk v Wolff)
The movie is a simplified and more modern line than the game it was based on.
[FEN ""]
[Event "?"]
[Site "?"]
[Date "2020.08.24"]
[Round "?"]
[White "Harmon"]
[Black "Borgov"]
[Result "1-0"]
[ECO "D20"]
[PlyCount "105"]
[SourceVersionDate "2020.10.31"]

1. d4 d5 2. c4 dxc4 3. e4 Nc6 4. Be3 Nf6 5. Nc3 e5 6. d5 Ne7 7. Bxc4 Ng6 8. f3 Bd6 9. Qd2 Bd7 10. Nge2 a6 11. Bb3 b5 12. a4 O-O 13. O-O Qe7 14. Rac1 Nh5 15. g3 h6 16. Bc2 Rab8 17. axb5 axb5 18. Ra1 Ra8 19. Bd3 Bb4 20. Rxa8 Rxa8 21. Qc2 Bc5 22. Nd1 Bd6 23. Nf2 Nhf4 24. Rc1 Qg5 25. Kh1 Qh5 26. Ng1 Nxd3 27. Nxd3 f5 28. Nc5 Bc8 29. Rf1 Ne7 30. Qd3 fxe4 31. fxe4 Qg6 32. Kg2 Kh7 33. Nf3 Ng8 34. Nh4 Qg4 35. Nf5 Nf6 36. h3 Qg6 37. Ne6 Ra4 38. b3 Rxe4 39. Nxd6 Bxe6 40. dxe6 cxd6 41. e7 d5 42. Bc5 Qe8 43. Qf3 Qc6 44. b4 Qe8 45. Qf5+ Kh8 46. Qxf6 gxf6 47. Rxf6 Qh5 48. Rf8+ Kg7 49. e8=Q Re2+ 50. Kf1 Qxh3+ 51. Kxe2 Qg2+ 52. Rf2 Qe4+ 53. Kd2 1-0

The Game that its based off
[FEN ""]
[Event "Biel Interzonal"]
[Site "Biel"]
[Date "1993.??.??"]
[Round "1"]
[White "Ivanchuk, Vassily"]
[Black "Wolff, Patrick G"]
[Result "1/2-1/2"]
[ECO "D20"]
[WhiteElo "2705"]
[BlackElo "2585"]
[PlyCount "144"]
[EventDate "1993.07.??"]
[EventType "swiss"]
[EventRounds "13"]

1. d4 d5 2. c4 dxc4 3. e4 Nc6 4. Be3 Nf6 5. Nc3 e5 6. d5 Ne7 7. Bxc4 Ng6 8. f3 Bd6 9. Qd2 Bd7 10. Nge2 a6 11. Bb3 b5 12. a4 O-O 13. O-O Qe7 14. Rac1 Nh5 15. g3 h6 16. Bc2 Rab8 17. axb5 axb5 18. Ra1 Ra8 19. Bd3 Bb4 20. Rxa8 Rxa8 21. Qc2 Bc5 22. Nd1 Bd6 23. Nf2 Nhf4 24. Rc1 Qg5 25. Kh1 Qh5 26. Ng1 Nxd3 27. Nxd3 f5 28. Nc5 Bc8 29. Rf1 Ne7 30. Qd3 fxe4 31. fxe4 Qg6 32. Kg2 Kh7 33. Nf3 Ng8 34. Nh4 Qg4 35. Nf5 Nf6 36. h3 Qg6 37. g4 Bxc5 38. Bxc5 Ra4 39. Rf3 Rc4 40. Be7 Bxf5 41. Rxf5 Rd4 42. Qe3 Rxe4 43. Qf3 Rf4 44. Rxf4 exf4 45. Bxf6 Qxf6 46. Qd3+ Qg6 47. Qe2 c6 48. Kf3 cxd5 49. Kxf4 Qf6+ 50. Kg3 Qd6+ 51. Kf3 b4 52. h4 Qf6+ 53. Kg3 Qd6+ 54. Kf3 Qf6+ 55. Kg3 g6 56. Qe8 Qd6+ 57. Kf3 Kg7 58. g5 hxg5 59. hxg5 d4 60. Qe4 d3 61. Qb7+ Kf8 62. Qc8+ Ke7 63. Qb7+ Ke6 64. Qe4+ Kd7 65. Qb7+ Kd8 66. Qa8+ Kc7 67. Qa7+ Kc8 68. Qa8+ Kc7 69. Qa7+ Kc6 70. Qa6+ Kc5 71. Qxd6+ Kxd6 72. Ke3 Ke5 1/2-1/2

I believe the Kentucky game to be based of Nezhmetdinov vs Kasparian game as well.
[FEN ""]
[Event "Spartak Team Ch (1955), Riga LAT"]
[Site "?"]
[Date "1955"]
[Round "?"]
[White "Rashid Gibiatovich Nezhmetdino"]
[Black "Genrikh Kasparian"]
[Result "*"]
[ECO "B11"]
[PlyCount "93"]

1. e4 c6 2. Nf3 d5 3. Nc3 Bg4 4. h3 Bxf3 5. Qxf3 e6 6. g3 g6 7. Bg2 Bg7 8. O-O Nd7 9. Qe2 d4 10. Nb1 e5 11. d3 Ne7 12. f4 Qc7 13. a4 O-O 14. f5 f6 15. Nd2 Bh6 16. Kh2 Kh8 17. fxg6 hxg6 18. Nf3 Bxc1 19. Raxc1 Nc5 20. c3 Nb3 21. Rcd1 Rad8 22. Nh4 Qc8 23. Bf3 Qe6 24. Bg4 Qf7 25. Nf3 Qg8 26. h4 Kg7 27. Rf2 Rd6 28. Rdf1 Rdd8 29. Qc2 b6 30. h5 c5 31. hxg6 dxc3 32. bxc3 c4 33. d4 exd4 34. cxd4 Nxd4 35. Nxd4 Rxd4 36. e5 f5 37. Bxf5 Qd5 38. Be6 Rh8+ 39. Bh3 Nxg6 40. Rf7+ Kh6 41. Qxg6+ Kxg6 42. R1f6+ Kg5 43. Rf5+ Kg6 44. R7f6+ Kh7 45. Rh5+ Kg7 46. Rg5+ Kh7 47. Bf5# *

I will try to pin all the games I can find in the show so this list is likely to grow.


This seems to just be a version of Chess960 restricted to certain openings to make castling more like "normal". Thus the positional considerations should be identical to regular chess, and regular chess principles (e.g. control the centre, develop your pieces early, gain space, etc.) should apply with equal force here.

What does change is the pattern recognition, to an extent. Particularly for how to handle the minor pieces, the intuition built up by playing normal chess (put knights on f3/c3, bishop to c4/b5, etc.) is gone.

Undefended pawn in the starting position: Obviously this can be a target for early attacks. Watch out for these, and be alert for tactics that could win/lose you a pawn.

Generalised opening principles: The usual chess opening ideas of controlling the centre, developing minor pieces and getting the king to safety should still apply. However, some of those ideas are specific cases of principles applicable to other chess types and variants:

Mobility. In the overwhelming majority of chess variants, mobility is the key principle, I would say even the most important one. Development is about improving your pieces' mobility. Controlling the centre is also about getting more mobility. Having more material means you have more pieces, and hence more options (more mobility!) than your opponent. Aim always to improve your pieces' mobility.
Speed. In developing your pieces, you want to do so as quickly as possible. Finishing development first means you can start to increase the pressure on your opponent before they have the chance to react.
Piece coordination. This is less focused on in regular chess than in other chesses like xiangqi and shogi. It ties in with the previous two points: you want to get your pieces to their optimal locations quickly (speed) such that they don't get in each others' way, and hopefully work together to control some squares (mobility).

So for the opening phase of Kratos chess, for instance, you'd want to look at your position and identify some kind of deployment of forces that, as a whole, brings your army to life. Try to identify the pieces that seem the hardest to develop, and work out a plan to get them active; don't neglect it and focus too much on your other pieces to the point where they get in the way of the neglected piece.

And of course plans must change with enemy contact. At every move, try to make sure your moves give you the flexibility to satisfactorily develop the rest of your pieces in as many ways as possible, so that you can adapt your plans if necessary.


Why are world-class engines playing like this?

Basically, the first four moves were implemented to start a game without the f2 pawn, i.e., with an imposed handicap. The game starts at move 5 with a French Defense set-up for Black. I'm surprised that Lc0 can win against Stockfish with a pawn down. I would probably have chosen to play e5 than e6, with the idea to install a Bishop in c5 and try to take advantage of the open g1-a7 diagonal.

I was also intrigued by some of the positions and their seemingly dumb moves, but some of them are not that dumb!

You mentioned a first puzzling moment after 9.g3

Lc0 has a pawn down and Stockfish plays to win with Qd8! By taking in h1 Stockfish could be even worst. Then, we may question the Qd8-h4-d8 sequence that has the advantage of weakening the kingside but loses two tempi. Reacting by c5 instead of Qh4 was probably more natural.

[FEN "rnb1k1nr/ppp2ppp/4p3/3pP3/1b1P3q/2N3P1/PPP4P/R1BQKBNR b KQkq - 0 1"]
[title "Position after 9. g3"]

9... Qd8! {was played and Lc0 has a pawn down and Stockfish plays to win with Qd8!} (9... Qe4? {is the obvious move but} 10.Kf2 Qxh1 (10...Bxc3 11.bxc3 Qxh1 12.h3!! is a transposition) 11.h3!! 11...Bxc3 12.bxc3 Qe4 13.Nf3! {White can maybe play for a win here because I don't see how the Queen escapes!} (13.Bd3 Qh1 14.Bf1=))

The second one is after the massive exchanges 41.Be2

White has winning chances in this endgame and Stockfish tries to find some counterplay by playing 41... d4. Assume Black waits and plays Bb7-Ba8 without playing d4. Then, the winning plan for White is to bring the King to h5 to collect the h6 pawn.

[FEN "2b3k1/p4p2/1p2pP1p/1P1pP2B/P7/6P1/7P/6K1 w - - 0 1"]
[title "Position after 40... Bxc8"]

1.Be2! d4 (1...Bb7 2. Kf2 Ba8 3.Kf3 Bb7 4.Kg4 Ba8 5.Kh5 Kh7 6.Bd3 Kg8 7.Kxh6+-)

Update. There are still some positions where like @polfosol I can't understand Lc0 moves! For instance, after 78... Bh7, the move 79.Kc3 seems indeed quite "dumb"! After 79.Bc2! the win is very easy (at least for a human ;-).

[FEN "4k3/p4p1b/1p2pP2/1P2P1PP/P7/8/1K6/3B4 b - - 0 1"]
[title "Position after 78... Bh7"]


Why is 3. Nc3 played in mainline of the Modern Defense?

3. c4 will likely transpose to a King Indian defense while 3. Nc3 will likely lead to a Pirc. 1. e4 players will prefer the more familiar Pirc positions.

The Modern Defense move order lets White decide the main position.


Is it possible that a radically different but equally effective playstyle exists?

It's definitely possible there are strategies we don't know about. However, training your engine to specifically play contrary to all we know isn't the way to get there. For example, what would you do if one of your pieces were threatened? Our current knowledge says to not give it up for no reason, so would your AI therefore decide to give it up (because it's technically mathematically possible there could be some hidden idea 30-40 moves down the road?). You'd do better with random moves.

A better way to unlock hidden strategies is through a more bottom up approach. For example, AlphaZero learned on its own (without human knowledge), just using the rules of the game to guide it. From this, we saw a new style of playing that was basically unknown. But trying to get this new style of playing wasn't the primary goal.

Basically, it's fine to disregard human knowledge, but it's not fine to actively train an AI to play opposite to this knowledge. Here you're just trading one well established knowledge base for a vastly poorer one.


How to play against an engine using scidb?

On this page, you can see that Scidb is not intended to be used to play against an engine.

You can use scidb for game analysis (click on the train button in the board tab), chessx to play against the computer (and game analysis too) and raptor chess interface or Jin to play on FICS (Free Internet Chess Server). These softwares all work on Linux. Other softwares are availble on Windows and OS X.


Between 1.d4 and 1.Nf3, what is the White first move that generally leads to the most solid, positional, slow, closed, strategic and quiet positions?

I'm a ~1750 Elo player and I've been thinking of switching my opening repertoire for White. ... And I don't want to get into solid, strategic and quiet positions because I suck at tactics (it's not the case, I played the Sicilian for 3 years, and did more than 5000 tactical puzzles). ... Maybe you still think that playing wild games full of tactics everywhere will make me improve faster ...

First of all, it is exactly the quiet positions that help improve a player, not the tactical ones. Everybody learn tactics, anyone can find mate in five when playing their own game so the only thing you should do is just keep solving puzzles and that's it. Your tactical skill will always be high, but never at the level of a GM. Why? Because some sacrifices are positional and are made with the intent of getting long-term compensation instead of mating in five or returning the sacrifices material. In order to master these, you need a strong understanding of middlegame positions that may arise from the openings you play.

Furthermore, with "quiet" play, you actually play chess instead of doing mindless checking for tactics, which will greatly help you improve. In quiet positions, you must still calculate and check for tactics, but you also must frequently decide which pieces are good to exchange and which are not ( this is very helpful when transitioning into endgame -> you would be surprised how often "tactical players" of high skill make banal mistakes in this area! ), you must take into account endgames that may arise and above all, you always have to evaluate pawn structure that may arise after every move played. To master "quiet" games you will need a lot of work on endgames, pawn structures and middlegame plans, but you will get so much in return -> you will be able to effortlessly grind down lesser players, outplay "tactical players" of equal rating, and offer very strong resistance against stronger players. So I understand exactly where you appeal for closed games comes from and will try to help you as best as I can. And for the record, playing "quiet" games will make you become GM faster than playing tactical games. GMs/IMs do not make mistakes in pure tactical positions, those are just well explored and every master knows them by heart. Tell me when was the last time you saw Sicilian Najdorf in World Championship match?? You will always see 1.d4 because of reasons that are too broad to be posted here...

  So my question is: between 1.d4 and 1.Nf3, what is the White first move that generally leads to the most solid, positional, slow, closed, strategic and quiet positions?

These two overlap, technically you can find all the 1.Nf3 openings transpose into certain opening lines that start with 1.d4.

The only sharp opening that is dangerous for your style of play is King's Indian Defense, since it requires a lot of learning, is sharp and some lines are extremely theoretical. Other nonsense, like BenOni or Chigorin defense are just rubbish and should not phase you ( BenOni is nearly refuted with Taimanov attack and you can bypass the Chigorin defense by simply playing Nf3 before you hit with c4 ) since most of the time White has an advantage or can simply dodge them altogether.

The problem with 1.Nf3 approach is that you can not battle Queen's Gambit Declined with favorable version of the Exchange variation and there are other openings where early Nf3 reduces your chances for obtaining an advantage. Still, this move offers you big practical chances to outplay your opponent with transpositional tricks. I haven't played active chess for quite some time ( 10+ years to be precise ) but let me show you on a small example what I am talking about:

[Title "Black wants to play with full center, but is tricked into passive position"]
[fen ""]

1.Nf3 Nc6 2.d4!

and Black has blocked his c-pawn thus condemning himself to passive play if he enters pawn structures with d5+e6, so he should aim for e5+d6 pawn structure with 2...d6 but White may play 3.Bf4, keeping e5 square in his control. The tactical shot 3...Nxd4 fails due to 4.Qxd4! e5 5.Nxe5 dxe5 6.Qxe5+ +-. He could try to go for e5 with 2..Bg4 but then simple e3 will force him to exchange the bishop for a knight in order to enforce ...e5. Although you allowed ...e5 you got bishop pair in return. This is known as trading one advantage for another and is important concept in positional play. With 1.Nf3 most of your games will be of this type, but you will have to cover a lot of theory so you can take the maximum transpositional tricks can offer you. Furthermore, you you have a chance to dodge the sharp lines:

[Title "White dodges King's Indian Defense"]
[fen ""]

1.Nf3 Nf6 2.g3 g6 3.Bg2 Bg7 4.O-O O-O 5.d3!? d6

And now you could play c4, e4 or even c3 going for b4 and action on the queenside. The position is stable for both sides so the player with broader knowledge and higher creativity will prevail. The point of 1.Nf3 is that you must have a vast opening knowledge and strong grasp of typical middlegame positions like Isolated or Hanging pawns, various exchange lines ( like in QGD, Slav, French defense and so on...) and even main lines, so you can successfully decide in which direction to steer the game.

As for 1.d4, things are different. This move reduces the amount of work you must invest in learning the pawn structures/middlegame plans and variations, but offers Black great chances to sharpen the game. Various gambits, King's Indian defense and so on are now a real option. You would have to accept that sometimes you will have to play mind-blowing, wild tactical games, you initially wished to dodge. Your biggest problem will be Nimzo-Indian defense since it scores very well against 1.d4, but you can dodge it by playing Nf3 instead of Nc3. Although the subtle move order can take away best response for Black, you too must pay the price. Black may play Queen's Indian defense, which gives White a small advantage but is considered drawish, or he can trick you and choose to play Queen's Gambit since the most dangerous reply -> the Exchange variation after cxd5, is harmless for him since you have Nf3 instead of Ne2.

In my opinion, 1.Nf3 will offer you solid and strategic positions you seek, but you will have to work harder and be ready to make more draws than wins since most of the time the best options for White can be bypassed by Black.

Comparing 1.d4 vs 1.Nf3 further would be too broad, so I will ask you to leave a comment if you need further help. In the end, here are some books I would recommend:

For 1.d4:

B.Avrukh-Grandmaster repertoire 1;
B.Avrukh-Grandmaster repertoire 2;
B.Avrukh-Grandmaster repertoire 8;
B.Avrukh-Grandmaster repertoire 9;
B.Avrukh-Grandmaster repertoire 10;
B.Avruhk-Grandmaster repertoire 11;
L.Shandorff-Playing the Queens Gambit ( second edition! );

For 1.Nf3:

A.Khalifman-Opening for White according to Kramnik ( all of the books in the series! );

Good luck and best regards.


Are there any legal positions known to be impossible to come to in a normal game?

Hi and thanks for the question. The words "legal" and "illegal" are actually defined in the FIDE rules. Basically, a legal position is one which can be reached by a sequence of legal moves.

So, with this definition, I think that you are asking: are there illegal positions which aren't obvious? The answer is "many" Welcome to retrograde analysis! :D

There is already a chess.stackexchange question on this, so I suggest we continue the discussion there: Are there any illegal positions that are difficult to spot?


To get evaluation score for each legal move, you can do:

Set MultiPV to a high number, like in your answer
Play the moves, then invoke SF on each of the resulting FEN. For example, in the starting position you could start 20 SF instances, one for each possible move. This is the approach adopted by commercial companies, such as Chessable.

The first approach works but it's slow and not exactly scalable.

PS: Asking for Python code is off-topic here. We can guide you but we won't write code for you.


So far, studies I‘ve seen mentioned in newspapers making a claim either for or against a correlation between chess and intelligence strike me as highly dubious in their methodology. That‘s not surprising, since the concept of a “general intelligence” is itself dubious. (And it’s not even entirely clear in every context what “intelligence” actually means.)

Chess is basically a duel that two people fight with their minds. One would expect that as a pastime it’s more attractive to people who enjoy exercising their minds in various areas in general. Therefore, it wouldn’t be surprising to find that among good chess players there would also be more people than average that are good at mathematics, spatial visualisation, music and arts, programming etc.

(Speaking metaphorically: A rooster makes cock-a-doodle-doo, because the sun goes up. It's not the other way around: The sun doesn't rise because of the rooster.)

Developing, for instance, a good memory for chess games and long variations doesn’t automatically grant a good memory for reciting poetry or repeating the dance steps in a choreography or the memory necessary to keep one’s focus through deciphering a particularly difficult classical Greek text. Nor does it make you good at drawing portraits (which is for a very substantial part about having a good short term visual memory).

There might be some soft form of synenergy in that playing chess increases brain activity, brain metabolism etc. which conceivably might have a positive effect on other mental activities. That, though, would also go the other way around.


What is the best way to improve Crazyhouse or Bughouse skills?

Since there isn't much material out there to study, the best way is to play with better players.  Of course, studying tactic problems is great for chess and the variants. FICS (free internet chess server) is probably where the best Siamese (bughouse) players are.

It helps if you have some opening systems worked out (since in Siamese being ahead on the clock can be crucial).
Published tips are here: http://www.freechess.org/Help/HelpFiles/bughouse_strat.html
https://www.chess.com/blog/Sorsi/advanced-bughouse-tips


How to determine checkmated positions using DOS/CMD, from numerous FEN/EPD chess positions?

I don't know if any such tool exists. If you want to program yourself you need to watch out for:

Change of mating theme: If you remove pieces you might get new/different mates, e.g. in:

    6rk/5Npp/8/8/8/8/2K5/7R b - - 0 1

if you remove the white knight and the black pawn on h7 you have a new mate, which might not be desirable.

Impossible positions: If you remove pieces you might end up with positions that cannot be reached in normal play. This can be as easy as positions where three pieces attack the king at the same time, but it can also be a lot more difficult. So in addition to checking for mate, you also need to run some retrograde analysis to check whether the position is legal


How often does FIDE review clocks to update their approved list?

They seem to have just finished the process literally YESTERDAY, but the new clocks have not made it into that list.

You would think that there would be a set of criteria that a company would have to meet, and if met, then they would get approval, but it appears to be more of a "money thing" than a "this-clock-is-good" thing.

I remembered looking for that when I was buying my clock, and they appear to do it as a bidding process, in other words, the companies pay for the right; and if they pay enough, they are approved.

https://www.fide.com/news/77

https://www.fide.com/news/346 (Note the date: Friday, 31 Jan 2020)