# Question
Title: In the English Opening, where should the d-pawn go?
Whenever I play the English Opening, I usually try to achieve a c4, d4, e3 pawn structure. However, in this video by STL chess club, the instructor recommends playing d3 (and possibly e4 later) to control the white squares as much as possible.

Which is objectively better? Does it depend on the opponent's play?

# Answer
Once you play d4 you are usually leaving the pure English opening and transposing to a queen-pawn opening. Objectively there are positions where it is absolutely better to transpose to a queen-pawn opening but you can certainly build a repertoire around playing the pawn to d3 -- it may just be easier for Black to equalize in some lines.

The formation of c4, d3, e4 with the kings bishop fianchetto'd, knights on e2 and c3 was Botvinnik's baby and is a viable way to play.
> 6 votes

# Answer
It depends on your opponent's play and your own tastes. Neither are objectively better on their own merits. Yes, c4-d3-e4 does control the light squares, but it grossly weakens the central dark squares (especially d4). Your setup with c4,d4,e3 goes for broad central control, but is rather slow (sometimes allowing Black to strike first with ...d5).

There's nothing wrong with pushing the d-pawn to d4. However, for the sake of speed in some positions, consider just playing c4 and d4 (omitting the move e3).
> 3 votes

# Answer
One aspect of the English opening is that White retains a lot of options. He believes that c2-c4 will be a useful move in many different situations, so he may play with the idea of keeping his intentions concealed, or with the idea of leaving Black to disclose his intentions first. But it is also possible to play the English having a certain setup, such as the Botwinnik c4, d3, e4 structure, in mind. A common mistake is to do nothing but play "flexible" moves, and leave Black with a free hand to whatever he wants. Keep these considerations in mind as you play through some master games, and imagine whether you would feel comfortable in the situations that arise.
> 1 votes

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Tags: opening, pawn-structure, english-opening
---


title: Are isolated passed pawns good or bad?

text:
# Question
Title: Are isolated passed pawns good or bad?
I frequently face situations in the late middle game (perhaps only a one minor piece and a rook or two on each side, no queens) where I can force a position (via exchanges) where both players are materially equal but I have an isolated passed pawn on the 4th or 5th rank. I have heard that isolated pawns are bad (because they cannot be supported by other pawns) but also that passed pawns are good. Are isolated passed pawns generally good or bad? Is it good to create them?

I realize the answer probably depends on the position, so guidelines for determining when such pawns are good or bad would make for a great answer.

# Answer
I'm happy when I have a passed pawn, and my opponent has none. Yet, connected passed pawns are much better than isolated passed pawns.

Here are the raw advantages of a passed pawn:

* A passed pawn can no more be exchanged against a pawn, so if it gets exchanged, it will be against something bigger.
* If a passed pawn is defended by a non-passed pawn, and the opponent decides to exchange a minor piece against your passed pawn, the defending pawn becomes a passed pawn in turn, keeping your passed pawn advantage, in addition to gaining material. It makes it a little more difficult for the opponent to actually do this.

Still, there are caveats with regards to an isolated passed pawn:

* Since your passed pawn can't be defended by another pawn, you'll have to mobilize something bigger to defend it. (leaving less material to act on the issues of the rest of the board)

But:

* If you can have a rook defending your passed pawn from behind, you have one less rook on the rest of the board, but you can easily threaten to gain material by appropriately pushing your pawn.
* If your opponent decides to block your pawn with a piece, to prevent you from pushing, well, that's one less opposite piece playing on the rest of the board.
* If your opponent decides to exchange your pawn, you end up with a rook on an open file.

In the endgame, connected passed pawns beat the opposite king:

* If they are side-by-side, they setup a wall of 4 controlled squares, so can't be threatened by the opposite king.

\[fen "8/4k3/8/3PP3/8/8/8/8 w - - 0 1"\]
* If they are connected, one row apart, the king has to capture the rear pawn first, effectively leaving the front pawn's promotion square.

All these are limited to what the specifics of every position allow.
> 10 votes

# Answer
> I frequently face situations in the late middle game (perhaps only a one minor piece and a rook or two on each side, no queens) where I can force a position (via exchanges) where both players are materially equal but I have an isolated passed pawn on the 4th or 5th rank. I have heard that isolated pawns are bad (because they cannot be supported by other pawns) but also that passed pawns are good. Are isolated passed pawns generally good or bad? Is it good to create them?

If you could provide just a little bit more info, I could try to help you with greater confidence. For now, I must make following assumptions before answering your question:

* The endgame is one with rook + *at least one* minor piece;
* You have an isolated passed pawn, but your opponent *does not*, meaning he has *pawn majority on one side* so is able to create a passed pawn;
* Your passed pawn has advanced far ahead ( 4th or 5th rank will be far enough for any color );

In such cases it is important to tell us about following:

* You must list *exact type of minor pieces for both sides* ( bishop vs knight, bishop pair vs knight and bishop... ) since we already know there is a rook on each side;
* The *exact pawn structure* since the position of the isolated pawn is crucial, as well as the opponent's ability to create a passer of its own;

Only after having this info, will you be able to decide whether the isolated pawn will be strength or weakness.

> I realize the answer probably depends on the position, so guidelines for determining when such pawns are good or bad would make for a great answer.

Since your current question does not fulfill all the criteria listed above, I will try to "cover as much ground" as possible, while trying to keep this answer brief.

OK, now let us begin:

The basic outline is to use the passer to deflect the opponent's pieces so you can make a decisive break on the other side of the board.

The best way for this would be if isolated pawn is far away on the wing, and the worst would be if it is in the center.

Furthermore, you must secure your passer from being blockaded ( this is mandatory! ). Do not be afraid to exchange pieces if the ending is good for you. This is very powerful weapon in such endgames.

Next, `R + minor piece(s)` type of endgame is all about minor pieces. Pawns are irrelevant at the moment.

Here, you would like to have `R + B vs R + N` scenario, since `R + B` usually overpowers `R + N.` The passer will be only an asset, because it will deflect the opposing pieces and you will be able to use long range of the `R + B` to wreak havoc on the other side of the board. Do not forget to not allow opponent to block the isolated pawn.

`N + R vs B + R` will be harder for you, since the bishop is so fast that he can control the passer and aid in creation of its own passed pawn. Here, you should aim for a draw by exchanging the isolated pawn for the opponent's extra pawn ( and still it might get tough for you to hold the endgame! ). The best case scenario would be for both sides to have pawns at only one side of the board.

`R + B vs R + B` depends on the color of the bishops. With opposite colored bishops remember that the side with the initiative wins. Otherwise everything depends on piece activity and placement of your isolated pawn. I would not push him too far since it will become a weakness most of the time. Prepare for a long defense..

`2B + R vs 2B + R` is all about piece activity and square control, pawns are irrelevant. The side with the initiative wins. This is entirely position-specific, and if I were you I would probably keep all the pieces on the board while exchanging pawns only if it is forced or can help me get initiative/create a weakness.

`2N + R vs 2N + R` is all about initiative and pawn structure. Every piece position counts, and side with the initiative will usually win. This is so fragile, that you can probably assess the outcome immediately!

`2B + R vs N + B + R` should be heavily in your favor. Keep the pieces on, and use bishops to restrict the knight. Passed pawn is not a problem, since your long ranged pieces will protect it while also attacking the opponent's pawns. Passer will further restrict the opposing units, which will allow bishops to create weaknesses ( never underestimate their speed and ability to swiftly reposition themselves! ). Again, it is very important not to allow your passer to be blockaded. If that happens you always seek counterplay that is based upon breaking on the other side of the board by creating weaknesses there. Please remember this plan, it is crucial.

`N + B + R vs 2B + R`, might not be so bad since neither of opposing pieces is good at blockading. Still, their long range and speed will compensate for that and they will be able to support the creation of their own passer. Again, I would head for a draw here, by exchanging pawns so that they remain only at the one side of the board. Exchanging knight for a bishop is excellent here, but remember one important rule: If by any chance you end up in an ending with *opposite colored bishop* and a rook on each side, remember that side with the initiative wins.

`2N + R vs 2B + R` is not good, but if your knights are close to the passer and you can create swift action for promoting the pawn you can win. Otherwise, your opponent will use the bishops to both attack and defend, which will be hard to meet. Again, I would head for a draw by exchanging pawns so they are all at one side of the board and would exchange at least one knight for a bishop.

`2N + R vs 2N + R` is all about piece activity and pawn structure. You should concentrate on the positioning of the knights, and try to use rook to enforce a pawn weakness.

I have "ran out of steam" at the end but you get the picture...

Keep the bishops, and exchange knights for his bishops. Post your pieces actively and use the passer to restrict the opposing pieces. Create swift action on the other side of the board.

> Are isolated passed pawns good or bad?

It really depends a lot from the position so if you could edit your post I would be able to provide better help.

Hopefully this was helpful. If you need further help leave a comment.

Good luck and best regards.
> 7 votes

# Answer
One attribute is generally an advantage and the other is a disadvantage.

* Isolated pawns are weaker than connected pawns because they cannot be supported by other pawns.
* Passed pawns are an advantage because of the threat to promote.

When you combine the two, whether it is an advantage or disadvantage is dependent entirely on the position. You can have a passed pawn on the 7th rank, which is not defendable and is just a target. Or, the passed pawn can be supported by your other pieces and threatens promotion making it an advantage.

**Note**: Connected passers are generally better than isolated passers.
> 4 votes

# Answer
Sure, it all depends. But usually the most important question is can the pawn be blockaded. For example you have isolated passed pawn on d4, Black puts N on d5 and laughs at you. To play against an isolated pawn, Nimzovitch said it best..First restrain, (get several pieces controlling the square in front of it),then blockade (put one of them on that square; if it gets taken another piece will replace it), then destroy (attack and win it). But perhaps Black takes so much time to set that situation up that you can mount a big attack against his King. It all depends.

A pawn that cannot be blockaded is often a strength, but the exploitations can be various. A diversion to set up an attack elsewhere. Tying down the opponents pieces to allow you to march in with your King. And sometimes you can just promote the thing. If the Pawn is far advanced it may cramp your opponent more, but it also might be cut off from support. It all depends.

At some early stage of the game, there is often a choice between capturing/recapturing in ways that do/do not create such a pawn. If you are feeling aggressive, or if you believe that you are stronger than your opponent, you will tend go for the position with the isolated pawn, whether you or your opponent will have it. This is because you will (probably) be creating an unbalanced position with more chance of a decisive result, even if at the moment you do not see an advantage either way.
> 2 votes

# Answer
Read My System by Nimzowitch. You need to see examples where the isolated passed pawn is weak, and examples where it is strong. If your judgement on the matter can be consistently more accurate than that of your opponents, you will win a lot of games
> 2 votes

# Answer
Of course everything depends on the position, but isolated passed pawns have two properties that usually make them more of an asset than a liability:

They are fast:

```
3K4/8/8/5ppp/8/8/P4P1P/2k5 w KQkq - 0 1

```

In this position, although the black majority is already advanced, white still promotes first (and wins) even if black moves first. If the kings were on more realistic squares, this would mean, that the black king has to hurry to the passer and the white king could try to attack the black kingside.

Often losing them is a tolerable worst case scenario:

```
6k1/5ppp/8/8/8/8/6PP/6K1 w KQkq - 0 1

```

This pawn ending is lost, but … this position is generally still holdable for white IF there are still pieces on the board. So quite often you can try to promote your passed pawn on the queenside or the centre and still be confident to hold the draw if you mess it up and lose the pawn.

So I think the most likely scenario of a bad isolated passed pawn is one, where that pawn is safely blockaded and the other side still has the possibility to create an own passer on the queenside. So something like this:

```
8/4kppp/1p1n4/p2P4/8/2N6/1P2KPPP/8 w KQkq - 0 1

```
> 0 votes

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Tags: endgame, pawns, pawn-structure, passed-pawn, isolated-pawn
---


# Question
Title: Is there a reason AlphaZero hasn't been allowed to learn for longer?
Why don't the developers of AlphaZero let it learn for days, or even months on end? Wouldn't its neural network become much stronger, at the cost of just occupying some computational resources for a while? It seems like this would make it indisputably the best engine in world, since right now there's still controversy on whether it's clearly better than Stockfish.

If something like this already is happening, please correct me.

# Answer
Google's hardware is already very convincing. However, allowing a network running forever doesn't mean it'll play stronger chess. There is always limitation, in machine learning we say the network has reached "convergence".

Google developers must eventually stop the training, and evaluate it's performance. They would make a better model in the next iteration.
> 7 votes

# Answer
Check out the AlphaZero paper, figure 1.

As you can see from the leftmost figure, you can let AlphaZero train, but that doesn't mean it'll improve. In fact, AlphaZero peaked at a level slightly above Stockfish 8 (in other words, it'll likely lose to Stockfish 10).

I'm no expert, but I understand Leela is competitive with Stockfish 10 not because she has trained for longer, but because she's doing certain things that AlphaZero didn't do (such as "squeeze excitation" as in the latest Test 40).
> 12 votes

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Tags: engines, alphazero
---


title: Confusing question about the "Pawn"

text:
# Question
Title: Confusing question about the "Pawn"
I enjoy playing chess and thought that I knew all of the "rules." However, I just found out now something interesting but remain very confused regarding what exactly the "Pawn" is able to perform. This may be hard to understand, but as we were playing, my opponent that I was playing against had eventually moved one of his "Pawns" almost to my end of the board (more than half way) and then took one of my pieces using some kind of a crazy format move. I had always thought that in order for a "Pawn" to take an opponents piece, it had to take it with using only a one diagonal square move. In this particular case, he moved his "pawn" in two spots using a two step process, one diagonal and then one forward and then he took one of my pieces, which I had thought was in a very safe position.

What was this?

# Answer
> 3 votes
Check out en passant... a very common rule to overlook.

---
Tags: rules, pawns
---


# Question
Title: Why 5...h6 in the Tartakower Queen's Gambit Declined and not in the Orthodox Variation?
Why is the Tartakower Variation of the Queen's Gambit Declined almost always predeced by 5...h6, while in the Orthodox defense an early ...h6 is almost never played by Black?

# Answer
> 3 votes
2 main reasons:

* The orthodox defense typically goes for a ...c6 structure and avoids ...b6 + ...c5. This makes Bxf6 a more viable option for White due to the more closed nature of the game. So, ...h6 could just end up wasting a tempo by nudging White to make a somewhat favourable exchange. Note that it's fine for you to play Bxf6 against the Tartakower too, it just works better against the orthodox.
* The orthodox could see Black doing the maneuver Nbd7-Nf8-Ng6 (especially if White goes for a Carlsbad by exchanging on d5). This requires control over the g6 square if White has a Qc2+Bd3 battery set up. If Black has already played ...h6 and then plays ...Ng6, White wins a pawn with Bxg6 fxg6 Qxg6.

---
Tags: opening, queens-gambit-declined
---


# Question
Title: Do the rules of blitz chess allow a draw to be claimed if the position is dead drawn?
Consider this objectively drawn position that occurred in the Fischer vs Spassky 1972 match, game 12. Suppose this position occurred in a blitz game where Black barely has few seconds remaining on his clock. Black decides to give up the f5-pawn and instead sit comfortably with his pawns on f6 and h6 as follows-

```
   [fen "8/5p2/6kp/p4p2/2B5/1P2PK1P/8/4b3 w - - 0 1"]

   1. Kf4 f6. 2. Bd3 Bb4. 3. Bxf5+ Kg7.

```

This position is an impenetrable fortress. Because of the presence of bishops of opposite color, there is no way White can check the Black king or even try to win a pawn by attacking it. If White marches up the e-pawn, Black can simply capture. There is no way White can win. Black simply has to keep moving his bishop safely on the a5-e1 diagonal.

Now, since this is a blitz game and Black just has a few seconds left, White simply attempts to run Black out of time just by making legal moves without making any kind of progress. In such a scenario, would Black be allowed to pause the clock and claim a draw?

# Answer
> 8 votes
No. There is a rule like that for standard time controls (rule 10.2 under FIDE rules), however under blitz rules 10.2 doesn't apply. Appendix B, rule B.3.b:

```
b. Article 10.2 and Appendix A.4.c do not apply.

```

In blitz, the clock is just as much a part of the game as the board is. If you have a position like that with seconds left and your opponent has more, you are lost.

# Answer
> 5 votes
It is important to know the difference between "dead drawn" which can be a subjective evaluation and "definitely drawn", for example King versus King and no other material present on the board. Other examples are K+B vs K and K+N vs K. After that, things get a bit tricky. As long as the opponent has a theoretical chance of checkmating you, you still lose when your time runs out. For example, white has a Knight and black has a pawn on the h-file. Black loses on time, since it is possible to construct a checkmate with the pieces present on the board. Thus, it is better for black to get rid of the h-pawn in case of time trouble, in order to salvage a draw.

Thus, the answer is "No", you cannot claim a draw in blitz as long as your opponent has a theoretical chance of checkmating you with the pieces available on the board. In addition, if you fail to claim a draw in longer time controls, you will lose when your time runs out, for the exact same reason as stated above. So make sure to claim a draw while you still have time left on your clock in those situations!

# Answer
> 1 votes
This position is a draw but it is not known that both sides can play it right. Player's skill is the major factor in chess, not position potential. If an arbiter(any arbiter) had the right to declare such positions a draw, without both players agreeing, it would be irrational. Only positions that a player's skill is irrelevant(e.g. K+B vs K) can be declared as a draw by the arbiter. A position like the one you show here, can only be a draw if a 3-fold repetition occurs, the players agree to a draw, or the arbiter concludes that no player is trying to win the game.

EDIT: As @RemcoGerlich pointed out, only article 10.2 indirectly prevents playing solely on the time of the opponent and this article does not apply in blitz. So, I removed the part of the answer that said otherwise incorrectly.

# Answer
> 1 votes
*One exception :*

If you are playing **supervized** blitz (like in the World Cup, for instance), then the "Competition Rules" apply and you can claim a draw through article 10.2. See Annex B.3 of the Fide Handbook

In the given position, you could get a draw by stopping the clock, calling the referee, explaining clearly that you intend to move your bishop on the e1-b4 diagonal without giving it to the white King, take on e5 with Pf6 if White ever plays e4-e5, and that your opponent has no way to win by normal means.

In **un-supervized** blitz, however, the Rapidplay Laws apply and, well, if your opponent wants to keep on playing it becomes a wrist race and you may end up losing on time.

# Answer
> 0 votes
A common practice, although not to my knowledge in any rule book, is that if your flag falls, you only lose if there is a legal sequence of moves that ends with you being mated.

This will lead to anomalous situations, such as you having plenty of pieces and your opponent just King and one Pawn. This is a win for your opponent because there will be a sequence of moves, probably very stupid, in which you give away all of your pieces and the opponent promotes his pawn. This means that your chief objective, in the moments before flag-fall, should have been to capture that pawn.

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Tags: rules, draw, blitz
---


# Question
Title: Is it allowed to talk to your opponent in a tournament game?
Suppose my opponent in a tournament was running very low on time, and after move 40, presses the clock and leaves the board for a while, falsely believing they will get extra time on their clock. There have been many losses on time as a result of a similar situation. In this case, is it allowed to warn your opponent of the potential danger of flagging?

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

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

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

If your opponent has left the board and you remind him of the time control this cannot be interpreted as distracting or annoying. It is helpful.
> 17 votes

# Answer
Assuming the opponent got away from the chessboard, but nearby another game which takes place at a tournament, the only thing you should be careful, is not harassing the other players.

Whispering your opponent that he or she is gonna lose because of the 40 move bonus that didn't apply is noble. You show some class this way, something missing from a lot of chess players nowadays.
> 4 votes

---
Tags: rules, tournament, etiquette
---


# Question
Title: Is it possible to configure SCID to use English descriptive notation?
I'm going through a classic book (Reti's Modern Ideas in Chess), which uses English descriptive notation rather than algebraic notation. I see there is an online resource which has converted the book to algebraic notation, but is it possible to configure SCID to use English descriptive notation instead of the default? Links below.

http://www.openchessbooks.org/reti-mic/chapter1/combination.html https://sourceforge.net/projects/scid/

An example of the book notation is

```
4. P - Q Kt 4

```

Which converts to the algebraic notation of

```
b4

```

# Answer
> 1 votes
I looked through the help, the menus, and the option file. I didn't see anything that looked like it could do this.

Of course, SCID is open source. If you know programming, you could always add this functionality yourself.

---
Tags: notation, scid
---


# Question
Title: Should I calculate the ratings match-by-match or batch of matches?
I'm looking to implement a Glicko 2 library in my application. However the two libraries I'm considering are different. Firstly, they produce slightly different results for the same dataset (the default one given in the Glicko paper).

Second, and what I'm interested in, is how they calculate the results. Library 1 calculates each match one-by-one. That is, n-function calls to `calculateMatch()`. Library 2 takes the entire set of data (all matches and players) and seemingly calculates it in one batch (although I'm not 100% on this).

Does it make a difference if you calculate the results one by one or as one batch?

# Answer
> What I wanted to know was **does it make a difference if you calculate the results one by one or as one batch?**

According to Professor Mark E. Glickman -

> The Glicko-2 system works best when the number of games in a rating period is moderate to large, say an average of at least 10-15 games per player in a rating period.

Note the above link also gives Glickman's algorithms for Glicko 2
> 1 votes

---
Tags: rating, glicko-2
---


# Question
Title: Is there a specific penalty for intentionally damaging chess pieces or the board?
If a player intentionally damages a chess set (e.g. breaks a piece in two, cracks the board, etc.), is there a specific penalty under FIDE rules? I'm not talking about moving pieces around surreptitiously or attempting to obscure the current game state, but something like a player getting angry and, while lawfully moving their knight, they bite it with their teeth, drool on it, or crack it with their hands before putting it back down.

It seems like it *might* fall under Rule 11.1, which provides

> 11.1 The players shall take no action that will bring the game of chess into disrepute.

According to 11.6, such a violation "shall lead to penalties in accordance with Article 12.9."

Would such an act fall under this general rule of sportsmanship, or is there a specific penalty (or specifically no penalty at all) for this?

# Answer
First of all I would consider the Preface:

> The Laws of Chess cannot cover all possible situations that may arise during a game, nor can they regulate all administrative questions. Where cases are not precisely regulated by an Article of the Laws, it should be possible to reach a correct decision by studying analogous situations which are regulated in the Laws.

I think it should be obvious that the sort of behavior you describe is wrong even if there is no rule that explicitly says "biting, drooling on, or cracking pieces is not allowed". :-)

But you can also consider

> 11.5. It is forbidden to distract or annoy the opponent in any manner whatsoever \[...\]

I don't think any arbiter would question your claim of being annoyed if your opponent is chewing on the pieces!
> 35 votes

---
Tags: rules, fide, sportsmanship
---


# Question
Title: Is it legal to play a move without hitting the clock?
In the game Andrey Esipenko - Nihal Sarin (2018 World Blitz Championship), after 7. Qb3 c4 8. Qc2 Sarin plays 8... Bf5, and before he hits the clock, Esipenko plays 9. Qc1, but since Nihal has not pressed the clock Esipenko can't (this is the full video of the game).

As far as I understand this would lead to errors recording the game (because the DGT board only records a move when the clock is pressed). But how about the rules? Is this a breach? This is a blitz game and its obvious that both players let it go, but if either player appeals, who will get penalised?

# Answer
> Is this a breach?

No. Article 4.7 of the FIDE Laws of Chess defines when a move has been "made". Basically when your hand loses contact with the piece moved/captured/promoted etc. Once the move has been made the opponent may make a move. This applies whether clocks are being used or not.

If clocks are being used then the move is "completed" when the player presses the clock. If the player did not press the clock then it is completed when he makes his next move - article 6.2.1 -

> 6.2.1 During the game each player, having made his move on the chessboard, shall stop his own clock and start his opponent’s clock (that is to say, he shall press his clock). This “completes” the move. A move is also completed if:
> 6.2.1.1 the move ends the game (see Articles 5.1.1, 5.2.1, 5.2.2, 9.6.1 and 9.6.2), or
> 6.2.1.2 the player has made his next move, when his previous move was not completed

When increments are used it is important that a player making a move should have the opportunity to press the clock and gain the increment. This is covered in article 6.2.2 -

> 6.2.2 A player must be allowed to stop his clock after making his move, even after the opponent has made his next move.

Hence if the opponent makes his move before the player has pressed the clock then the player may press the clock without making a move and it is up to the opponent to press the clock back which most opponents would do immediately in a blitz game.

So, there is no breach, no penalty.
> 26 votes

# Answer
You can request for a clock press, reminding it to your opponent. 99% of the time people forget of the clock. What you can do is either show the clock to your opponent after he or she played, or let the clock roll and enjoy your free time to think. Obviously, showing the clock to your opponent is more noble that taking advantage of the situation. If you rush to play a move you end up missing a press both of you. It is a mistake from both sides, thus you both have same responsibility. If someone loses in a fisher style tournament due to time, because they thought they pressed the clock 40 times, too bad. Thus, it is a good idea to remind the clock to your opponent.
> 3 votes

# Answer
> Is this a breach?

Haven't read all the manual pages, but afaik yes.

Even if the opponent plays the next move, you have a right to stop your clock and force opponent to spend fraction of "their time"

In a timed game you can't get a free move. Free = costs no clock time.
> 0 votes

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Tags: rules
---


title: Rating system for 5000 players

text:
# Question
Title: Rating system for 5000 players
we belong to a state in India with over 5000 active players. FIDE rating tournaments and FIDE rated players are here but we wish to start a new internal rating system like the USCF or ACF rating systems. Are there softwares or websites for this? Kindly advise

# Answer
> 4 votes
It seems that rankade, our ranking system for sports, games, and more, fits your needs.

It's free to use and it's designed to manage **rankings** (and **stats**, including matchup stats, and more) for small to large groups of players.

Rankade doesn't use **Elo**, but its algorithm (called *ree* algorithm), although more complex (here's a comparison between most known rating system, including *Elo*, *Glicko* and *TrueSkill*), is similar to Elo if you play 1-on-1 matches only.

On rankade (besides other sports and games) we host many chess groups, clubs, and associations.

# Answer
> 3 votes
There are two alternative rating systems - Glick/Glicko-2 and EloRater.

I believe the author of EloRater is a member of this site - @JimGarner. You could try contacting him directly.

---
Tags: software, rating, websites, uscf
---


# Question
Title: What is this opening, can't remember name, driving me crazy
Image attached. May not be exactly right but looks something similar to this! Thanks\]

# Answer
> 6 votes
This is not an opening. This is an "idealised" set up for the white pieces which is unlikely to be possible in a normal game unless black plays something like the Hippopotamus opening. I put "idealised" in quotes because there is really no such thing as a universal ideal white set up. White's best set up depends on where black puts his pieces. All openings are a struggle to make your pieces "good" and your opponent's "bad".

# Answer
> 2 votes
This is not an opening but rather a set-up. I believe it is called by many as a bull head set up.

# Answer
> 2 votes
Sorry, but that isn't an actual opening. That is a diagram that demonstrates the "ideal position" for each white piece.

An opening involves both White and Black moves, and the Black player has a lot of influence over which opening ends up being played. For example, the White player may start with 1. e4 and an opening in mind, but it is the Black player who decides if he is responding with 1. .. e5 or 1. .. e6 or 1. .. d6 or 1. .. c5.

---
Tags: opening
---


# Question
Title: What does it mean when engine position scores change when following the "best" move
I'm particularly thinking of Stockfish here, since that is the one I use most, but it seems to happen with other engines.

Sometimes you have a position and the recommended move for white might be +1.7 say. So you make the move and then for black the best move is suggested as being +0.6.

Is this because:

A) The engine is not perfect, so if it can search 19 moves ahead, then after the move it can search one ply further into the game, and that reveals something that dramatically changes the score. If so, what does this tell us about the position?

**Or**

B) Does the engine take into account the possibility that the opponent won't play optimally. E.g. does the engine assign any value to traps that are avoidable. For example, Given a choice between going directly to a position, or transposing to that position via offering a trap you should clearly try the trap first. Would the engine agree? Is the score only reflecting the "best" line, or some average of possible lines?

# Answer
I assume you used Stockfish with a GUI because the sign of the score would have been different if you didn't.

First of all, Stockfish is well known for its instability. The strongest chess engine isn't the best engine for analysis. This is like your local chess instructor might be a better coach than Kasparov for you.

A is obviously correct. Furthermore, the search algorithm could change as the hash-table gets filled up. The more that the engine "knows" about a particular position, the better it can analyse for the next position.
> 6 votes

# Answer
Stockfish 9 and 10 had contempt set to 20 or so by default, so that the engine would avoid draws when playing against weaker opponents (i.e. most other engines and all humans). If you change the contempt to 0 when analyzing, that should bring the evaluations with white or black to move closer to the same number.
> 4 votes

# Answer
Yes, it's A). The engine is not perfect and can only search so far in a given time. When you make a move for White, the engine doesn't have to waste time considering White's other options anymore. It can focus on only searching down the sub-tree rooted at the move you just made for White.

It's hard to say what this means about the positions that Stockfish is calculating. You might be tempted to say that the positions are tense and very sharp. However, using quiescence search, Stockfish tends to avoid evaluating such positions and waits until the game calms down. So it's hard to infer what the positions are like.
> 2 votes

# Answer
Engines like Stockfish use something called the Minimax Algorithm, which in short means that the engine **always assumes best play** by the opponent.

That means it will not go for any traps if it sees a refutation that is beneficial to the opponent.

The algorithm basically works so that it looks at as many positions as possible, and applying an evaluation function to them. Stockfish is extremly fast at calculating positions and thus looking pretty far ahead, but its evaluation function isn't as precise as that of Komodo, for example.

As a consequence, the evaluation can vary quite a bit, depending on how many positions it had time to calculate. Playing a move obviously limits the search space, so the engine can give a better analysis of that specific position, so it's more likely to find something that has a major impact on the evaluation.

TL;DR: Answer A is correct.
> 1 votes

---
Tags: analysis, engines
---


# Question
Title: How should I play as White if Black Defends the Tartakover QGD without ...h6?
This question is related to another I just posted, but it is actually a different question: if Black Defends the Tartakower QGD without an early ...h6, and I am an Anti-Tartakower–Makogonov–Bondarevsky vartiation player (5... h6 6. Bxf6 Bxf6), should I take an early Bxf6 nonetheless, by my own initiative, or should I keep my Bishop on g5?

# Answer
> 4 votes
It depends on your own tastes, but I'd recommend not taking. Taking after ...h6 is justified because it essentially costs Black a tempo (i.e., playing ...h6). If you take without provocation then no one's losing tempi, you're just making an exchange.

If you really like trading on f6 then go ahead, but objectively you shouldn't have any advantage.

# Answer
> 4 votes
Be careful that you don't end up a tempo down in a known line, otherwise it is good to keep all your options open. h6 can benefit Black in giving luft to a castled king but overall it is a slight weakening of his position, so you should be encouraged to wait for Black to ask the Bishop it's intentions.

Overall, unless you have a concrete reason to take the knight you should keep the Bishop.

# Answer
> 2 votes
I think what's important here is a conceptual understanding of the openings involved. What you're essentially asking is whether or not Bxf6 is worth considering in something like the Orthodox Defense variation of the QGD or some Semi-Slav variation, and what are its differences compared to the the Bxf6 move featured in the Anti-Tartakower variation of the *Neo*-Orthodox.

Firstly, one of the key reasons for which people may play the Neo-Orthodox rather than the Orthodox (or Semi-Slav) is that the latter ends up being more passive and cramped than the former, while still being solid. However, it features a key weakness: it uses a tempo to move the h-pawn. Even though White generally prefers to maintain the bishop (at least for a while) and to maintain the pressure in the position, the Anti-Tartakower nevertheless becomes coherent in light of this, as it takes advantage of a "wasted" tempo. Additionally, it avoids some of the more theoretical lines of the Tartakower. However, despite this, it's still generally considered a slightly worse try for White compared to the main line with Bh4.

In the Orthodox Defense, however, Black generally plays 5...O-O or 5...Nbd7. If Black plays 5...Nbd7, then 6.Bxf6 is a poor move, as it reduces White's pressure on Black's position, it makes Black's position less cramped, and it improves Black's knight on d7, all of that without even needing to invest a tempo on the h-pawn. If Black plays 5...O-O, then 6.Bxf6 is transposing to the Anti-Tartakower (which, as discussed, is already regarded as arguably not being the best try for White) but where Black has an extra tempo (as h6 wasn't played). Therefore, you can quickly tell that it must be an objectively poor choice for White. And this allows us to also address the differences between Bxf6 in the Orthodox and Bxf6 in the Neo-Orthodox: Black having an extra (and highly valuable) tempo to get his queen-side minor pieces out. Therefore, typical Anti-Tartakower plans such as playing Qb3 and trying to put pressure on the queenside will not be as effective. Therefore, while Bxf6 in the Orthodox is probably not outright *losing*, it almost certainly sacrifices White's opening advantage.

It's also worth noting that the same applies in the Anti-Meran Gambit of the Semi-Slav (1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5). If Black plays the Moscow Variation (5...h6), then 6.Bxf6 is a good continuation for White. If, however, Black opts for something else (e.g. the Cambridge Springs Defence starting with 5...Nbd7), then 6.Bxf6 is no longer considered as good.

---
Tags: opening, queens-gambit-declined
---


title: Any suggested check list for beginners?

text:
# Question
Title: Any suggested check list for beginners?
is there a simple / basic / quick checklist that beginners can use when in super easy games? I am not worried about questions like pawn structure, applying pressure, maintaining momentum, I am talking super basic like, will my knight move open my queen to attack? did his pawn open his bishop to wreck my back line?

I am not worried about getting outplayed, I get frustrated that I didn't see the fact his bishop had a direct shot at my queen. Losing my queen isn't as much of an issue as the fact that I didn't even see it coming.

yes, super beginner, yes, I need a quick and dirty checklist to start with before I can even THINK about maintaining pressure and pawn formations.

# Answer
> 3 votes
The focus is mostly on the piece your opponent just moved, and the piece you are moving. Most of the time, a blunder will involve one of those two pieces. Most of the rest of the time, a blunder will involve a discovered attack or not noticing that a piece was pinned to something more valuable.

Ways to lose your queen in one move mostly consist of:

You move your queen to a spot where it can simply be taken.
You move another piece which was pinned to your queen, allowing it to be taken.
Your opponent moved a piece which is now attacking your queen, and you ignore it.
Your opponent moved a piece which allowed another of his pieces to attack your queen, and you ignore it.

So that suggests a basic checklist of:

* Make sure the piece you're about to move can't be taken for free.
* Make sure the piece you're about to move isn't pinned to another piece.
* Look at what the piece your opponent just moved is attacking.
* Check if your opponent's move allowed another of his pieces to attack you.

Ways to lose your queen in two moves mostly consist of:

Your queen gets pinned.
Your queen gets skewered.
Your queen gets forked.
Your opponent plays a discovered check which also attacks your queen.
Your queen gets trapped.

So the slightly less basic version of the checklist makes sure that your move does not allow any pins, forks, skewers, discovered checks, or trapped pieces, and that your opponent's last move does not threaten any of those.

And you should, of course, always be watching out for checkmate. It doesn't matter if you lose your queen if the game is over.

This is not comprehensive - there are other ways to lose your queen fast. But it does check for some of the most common basic-level blunders.

---
Tags: beginner
---


title: Bonus added at move zero

text:
# Question
Title: Bonus added at move zero
Is the bonus time added before the game starts, that is before the first move?

I play in a competition that has a time control of 1 hour 40 minutes +30 seconds per move. If I set the chess clock to this time control, the game effectively starts with 1 h 40 min 30 s per Player. Is this the correct behaviour?

# Answer
> Is this the correct behaviour?

Yes it is.

Consider the FIDE Rating Regulations -

> **1. Rate of Play**
> 1.1 For a game to be rated each player must have the following minimum periods in which to complete all the moves, assuming the game lasts 60 moves. Where at least one of the players in the game has a rating 2200 or higher, each player must have a minimum of 120 minutes.

The standard time control used in the vast majority of FIDE rated competitions is game in 90 minutes with a 30 second increment starting from move 1.

Suppose the increment is added after the player presses the clock and he starts with 90 minutes. After 59 moves his clock will show -
90 minutes + 59x30 seconds - time taken to make 59 moves
= 119 minutes 30 seconds - time taken to make 59 moves

In other words he is going to have less than 120 minutes to make 60 moves because the 30 second increment doesn't get added **until** he has completed 60 moves. If he takes 119 minutes 31 seconds to make 60 moves then his flag will have fallen before he presses the clock and gets the increment.

Adding 30 seconds before the first move corrects this.
> 3 votes

---
Tags: time-control, chess-clocks
---


title: Why was this game drawn?

text:
# Question
Title: Why was this game drawn?
So, I was having this game with my opponent (and losing), but anyways, here is the final position:

I checked the king with my knight on move 47 (i playing black). All of a sudden, the game was drawn by insufficient material rule. However, there was indeed a queen with my opponent there on the board. So, what exactly happened here?

Also take note that my opponent had no time on the clock, so practically, I should have won the game.

# Answer
Chess.com, along with FIDE, awards the full point to your opponent if you run out of time, *unless* your opponent has insufficient material: not enough resources to feasibly carry out a win. This effectually concedes victory to both players, which is sensible since on the one hand, your opponent rendered you incapable, but on the other, you held him off until he had no time to finish you off.

However, Chess.com's definition of "insufficient material" differs from FIDE's Laws. Chess.com simply looks at your material. If you have lone K, KN, KB, or KNN, you have insufficient material. So in your case, your opponent ran out of time, but since they determine that you could not have checkmated him anyway, Chess.com split the point.

Whereas FIDE calculates all possible futures; if one legal series of moves results in checkmate against the player whose flag fell, flag-fall is a loss for that player:

> 6.9
> Except where one of Articles 5.1.a, 5.1.b, 5.2.a, 5.2.b, 5.2.c applies, if a player does not complete the prescribed number of moves in the allotted time, the game is lost by that player. However, the game is drawn if the position is such that the opponent cannot checkmate the player’s king **by any possible series of legal moves.**

Just for kicks, let's see one of these legal series of moves wherein you checkmate your opponent.

```
[FEN "5Q2/8/8/8/2k2P2/6K1/4n3/8 w - - 0 0"]
[startflipped "1"]

1. Kg4 Kd4 2. Kg5 Ke4 3. f5 Nf4 4. f6 Kf3 5. Kh6 Kg4 6. Kh7 Kh5 7. Kg8 Kg6 8. Qe8+ Kh6 9. Kf8 Kh7 10. f7 Ng6#

```

That's why FIDE would count flag-fall to be a win for you. Chess.com does not. To be fair, that or any line resulting in victory for you is so far-fetched that in this case, it's hard to complain that you could feasibly have won.\*

Sources: FIDE Laws of Chess, Article 6.9; Chess.com forums - list of threads with "insufficient" in the title.

\*There are a couple positions, however, in which King and Knight can force a checkmate vs. King and Pawn. For example, there would be ample cause of complaint if Black purposely runs out of time in the following position:

```
[FEN "8/8/8/8/N7/p7/k2K4/8 w - - 0 0"]

1. Kc2 Ka1 2. Nc5 Ka2 3. Nd3 Ka1 4. Nc1 a2 5. Nb3#

```
> 13 votes

# Answer
As your opponent overstepped the time limit, it is **you** who has to have sufficient material to mate him, to claim a win. His material is irrelevant, but your knight isn't enough.

Unfortunately for you this decision might be dependent on the chess server you are using. With queen and c-pawn there clearly still is a "series of legal moves that leads to checkmate", so I'm not sure this would be a draw under Fide rules.
> 7 votes

# Answer
You're right, with the flag fallen, the game should have been awarded to you, because it is possible to create a mate starting at the given position (e.g. if the pawn is promoted to a bishop). Seems like this particular online chess doesn't implement the rules correctly.
> 4 votes

# Answer
If your opponent runs out of time but *you* have no possible way to checkmate, the game is declared drawn (by FIDE rules). The rationale is that you couldn't have won the game no matter what, so you don't get a full point.

In your game you technically could have won with only a knight if your opponent played very badly. So according to FIDE rules the server should have awarded you a win. However, the server doesn't have to abide by FIDE rules (personally I think the no mating material rule is fairer in this instance).
> 0 votes

---
Tags: draw, online-chess
---


# Question
Title: What kinds of unconventional chess problems exist?
What are some unconventional chess problems that ordinary chess engines can never solve? I'm attaching two examples below so that you can get an idea. My students seem to love these puzzles. I'm researching and learning about it now.

**EDIT**

* Thanks @ETD for pointing out that it's possible to create programs to solve, at least by brute force solutions to any chess problems. What I mean though is normal chess computers.
* EDIT 2: I realize that the question is a bit vague. What I really like to know is creative puzzles, which if given to a beginner player should not be solvable by putting it on his computer and running an analysis.

# Answer
> 7 votes
I will do the obligatory retro and proof game plug:

## Proof games

A type of problem where you are to reach the diagram position within a given number of moves.

A good introductory PDF by Alain Brobecker, featuring many "classic" problems that are well-known among the proof game community.

Jeff Coakley has a lot of shorter (but still tricky) 4-move proof games on chesscafe (although the site put them behind a paywall since 2014, the resourceful reader can probably figure something out...)

Another simple example (original by me): Reach the position after black's 4th move.

```
rnbqkbnr/1ppppppp/8/p7/3P4/8/PPP1PPPP/RNB1KBNR w - - 0 1

```

Shorter proof games of about 4 to 7 moves are pretty good for regular chess players, and you literally only need to know how the pieces move. Longer ones can go up to 30 moves (for a "normal" long proof game) or even over 180 moves (the longest I know of).

## Retrograde analysis

Given only the diagram position and the fact that it was reached in a legal chess game, determine some feature of the position like side to move, castling rights, en passant rights, whether a piece is promoted...

An excellent collection of simpler problems that slowly rise in difficulty.

A magnificent introductory text by Nikolai Beluhov, an excellent composer of such problems. (Link is to a post containing PDF attachment.)

Another easy example by me again (although the idea is not new): What was the last move played? (I don't even need to give you the side to move for you to solve it.)

```
8/8/8/8/8/4PP2/1PPPRKPk/4nQ2 w - - 0 1

```

# Answer
> 6 votes
This is an excellent source for problems from different range of difficulty, where you can find these types of problems:

* Selfmate
* Helpmate
* Reflexmate
* Retrograde Analysis

Which regular chess engines can't solve because solutions are not the best moves. (Actually, worst moves in selfmate problems for example)

# Answer
> 5 votes
Here is a fun puzzle:

Construct a legal chess game where

* white starts with `1. a3`,
* white delivers checkmate on move 5, and
* the last move is made with the rook that started on `a1`.

> Hint: Black takes the pawn on `a3`.

# Answer
> 3 votes
There is a branch of Problem Chess called **Fairy Chess Problems** with all kinds of stipulations.

However, there are specialised programs (e.g. Alybadix or Chloe/WinChloe) to solve fairy chess problems and nowadays problem composers routinely use them to verify the integrity of their creations. For more information, look at https://en.wikipedia.org/wiki/Software\_for\_handling\_chess\_problems

# Answer
> 2 votes
Try also Burt Hochberg's **Chess Braintwisters**, which often require "thinking outside the box" to a move that is logical but illegal (like promoting to a King) and thus would never be found by an ordinary chess-playing or problem-solving computer program. A couple of examples from that book have already been posted in this forum in reply to another question: Is there any position where not promoting(illegally) would be the best move?

# Answer
> 1 votes
Apart from non-standard problems (fairy chess, retrograde analysis, etc), there also exist particularly difficult regular chess problems which are used for testing chess engines, like Nightmare II. These might not be solvable by some engines/computers. Take a look at this list

---
Tags: problems
---


# Question
Title: Not in stalemate, but why is this a draw?
I was practicing with stockfish level 8, having two rooks in the endgame whereas stockfish has only one. At the 78th move, it was declared as a draw. But, it was not a stalemate. Can anyone please help me, finding out why is this a drawn match ?

# Answer
> 12 votes
The game ended because of the **50-Move-Rule**.

From Wikipedia:

> The fifty-move rule in chess states that a player can claim a draw if no capture has been made and no pawn has been moved in the last fifty moves (for this purpose a "move" consists of a player completing their turn followed by the opponent completing their turn).

The last capture was made by white at move 28. (Rgxg6), so the game is declared a draw on move 78.

# Answer
> 5 votes
You most likely played 50 moves without a capture or a pawn move. This is called the 50-move rule, which results in a draw.

Check back to around move 28. You should see the last capture/pawn move there.

---
Tags: endgame, stockfish, draw, rook-endgame
---


# Question
Title: What is the purpose of 12.a3 in the QGD Lasker Defence?
this is about queen gambit declined lasker defence :

```
[fen ""]
1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Be7 5. e3 O-O 6. Nf3 h6 7. Bh4 Ne4 8. Bxe7 Qxe7 9. Rc1 Nxc3 10. Rxc3 c6 11. Qc2 Nd7 12. a3

```

why or what is the purpose of 12.a3 ?

# Answer
> 1 votes
`12. a3` in this position is a very concrete move, and as such, the best way to understand its purpose is to play out a handful of the main variations *with* and *without* the `a3` inclusion. If it's difficult to do that on your own, keep an engine on your side while you're doing your exploratory analysis.

**Short answer:** `a3` is not necessarily needed for white here, as there are alternatives such as `Be2` (see Ivanchuk vs Carlsen 2012), but `a3` helps keep a slight additional edge for white, as in a number of lines that can ensue white will have stopped any options of `Qb4+, Qb5` (stopping white's castling) and `Nf6-Nd5-Nb4` (specially in lines where black opts for `b6.`) To see why either of these options are relevant, let's go through some lines.

**Longer answer** (annotated, first go through the lines without `a3`):

```
 [title "Without and with a3 from move 12"]
 [fen "r1b2rk1/pp1nqpp1/2p1p2p/3p4/2PP4/2R1PN2/PPQ2PPP/4KB1R w K - 2 12"]

 1. Be2 (1. a3 {for the sake of comparison, let's follow through with both sides similarly to the Be2 line in order to highlight the underlying difference} dxc4 2. Bxc4 b6 3. Bd3 Nf6 (3...Bb7 {connecting the rooks and defending c6 directly} 4. Be4 Rfc8 5. Bxc6 {if c6-c5 could be played after Be4, black would be fine, but the knight on d7 leaves the queen and bishop disconnected, therefore, leaves c6 stuck on c6 and black cannot muster enough defense to hold on to it. So in this subvariation black still loses a clear pawn. We can conclude that after a3, black cannot really proceed with dxc4 and b6 ideas to finish development. However, dxc4 followed by e5 seems like a better alternative, but that's another discussion altogether.}) 4. Rxc6 Nd5 5. Qe2 Bb7 6. Rc1 {thanks to a3, white's a safe pawn up, has avoided simplifications for black, kept a healthy pawn structure and is ready to castle and maintaining control over the open file. Thus, a3, clearly refutes Nf6-Nd5 and leaves c6 hanging for black, so let's do better for black now.}) {Simply focusing on kingside development and to prepare short castles} dxc4 {a key forcing line that emphasizes the importance of control of b4 square} 2. Bxc4 b6 {in order for black to finish development, a solution has to be found for the locked out c8 bishop, therefore, either one opts for the e5 break early enough, or sets up the bishop on the long diagonal with b6, with either pawn breaks c5-e5 postponed for later.} 3. Bd3 {white's immediate reaction should be to prevent black's easy development, which here is simply to pressure the vulnerable c6 pawn, so Bd3 both uncovers the semi-open file and keeps the option of Be4 to add more pressure on c6.} Nf6 (3...Bb7 {for completeness let's consider the immediate Bb7 as well} 4. Be4 {usually throwing a Bh7+ first is good, but for the purpose of our discussions here it's not so important.} Rac8 5. Bxc6 Bxc6 6. Rxc6 Rxc6 7. Qxc6 Qb4+ {b4's not controlled by white!} 8. Qc3 Qb5 {black's well compensated for the pawn as white's unable to finish development and bring its last piece into play, black seems to be well in time for Nf6-Ne4-Nd6 followed by Rc8 claiming the open file, while white's left with no real initiative or even a clear path to finishing development.}) {but Bd3 is not even with tempo because black doesn't even have to immediately respond to the defense of c6 as Nf6 followed by Nd5 indirectly defends c6 as it comes with a double attack threat of Nb4 either forking the rook and queen, or the queen and bishop.} 4. Rxc6 Nd5 5. Qd2 {side-stepping the fork} Nb4 {b4's not controlled by white!} 6. Rc3 Nxd3+ 7. Qxd3 Bb7 8. O-O (8. Qe2 {as an alternative attempting not to prevent the kingside damage and holding on to the extra pawn} Rfc8 9. O-O Rxc3 10. bxc3 Rac8 11. Rc1 Qa3 12. Qd2 Bd5 {black's completely equalized as white's both weak pawns are under pressure and white has no initiative, Rc2 Be4 can even potentially lead to repetition.}) Bxf3 9. gxf3 Qg5+ 10. Kh1 Qd5 {black's winning back the temporarily sacrificed pawn and has a perfectly playable position without any weaknesses. This shows that Nf5-Nd5 is a very strong idea and if white wants to stop all these forcing variations which heavily simplify and equalize the game, then the said knight maneuver has to be stopped.}

```

**Summary after our analysis:** Very concretely, `a3` puts a clear stop to `dxc4` and `b6` type of continuations for black (which would let them complete development comfortably), while maintaining the asymmetry of the position and avoiding simplifications which would favour black. Black on the other hand, still has a number of choices at their disposal after `a3,` one of which is `dxc4` followed by `e5,` either way, black has to have planned for a well-timed pawn break with `c5` or `e5` if and when they decide to take on `c4.`

# Answer
> 0 votes
The main reason is to prepare a b4 push. This is especially useful if a Carlsbad structure is reached (after cxd5 exd5), when White will try to launch a queenside minority attack.

Another reason is to stop Black's queen from intruding on the square, as well as the b8-knight (e.g., ...Na6 followed by ...Nb4).

---
Tags: opening, queens-gambit, queens-gambit-declined
---


# Question
Title: Why didn't Spassky play 26. g3 in game 5 of Fischer-Spassky (1972)?
Fischer's play was powerful in this Nimzo-Indian, achieving a strong knight against two bishops in a closed position. The knight became a monster on f4. But why did Spassky let the knight reach f4? The idea of playing 26. g3 to prevent the knight from getting there seems like an obvious idea. If not for f4, it's hard to find a good square for the knight. Sure, the move 26. g3 has some drawbacks, like weakening the light squares around white's king and making the dark-squared bishop even worse. But it looks like the benefit would outweigh the drawbacks. What are your thoughts?

I used the chessgames.com engine to analyze the position and was surprised to find that 26. g3 wasn't even in the top two moves. I wonder why this is? Why did neither Spassky nor the chessgames.com engine choose 26. g3 as a move?

```
[fen ""]
[Event "Spassky - Fischer World Championship Match"]
[Site "Reykjavik ISL"]
[Date "1972.07.20"]
[EventDate "?"]
[Round "5"]
[Result "0-1"]
[White "Boris Spassky"]
[Black "Robert James Fischer"]
[ECO "E41"]

1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 c5 5. e3 Nc6 6. Bd3 Bxc3+ 7. bxc3 d6 8. e4 e5 9. d5 Ne7 10. Nh4 h6 11. f4 Ng6 12. Nxg6 fxg6 13. fxe5 dxe5 14. Be3 b6 15. O-O O-O 16. a4 a5 17. Rb1 Bd7 18. Rb2 Rb8 19. Rbf2 Qe7 20. Bc2 g5 21. Bd2 Qe8 22. Be1 Qg6 23. Qd3 Nh5 24. Rxf8+ Rxf8 25. Rxf8+ Kxf8 26. Bd1 Nf4 27. Qc2 Bxa4 0-1

```

# Answer
> 5 votes
I'd actually argue that the drawbacks of g3 are worse than Black getting a knight on f4. White *permanently* weakens the kingside light squares and blocks in his dark-squared bishop. Meanwhile, Black getting a knight on f4 is a bit unpleasant, but it's not necessarily a permanent problem.

Spassky probably thought that after 26...Nf4 27.Qc2, he was holding. He missed 27...Bxa4 of course, but if he had played 27.Qb1 instead, Komodo actually gives an equal evaluation. It's funner to play Black, but finding a plan to breakthrough is nontrivial.

After 26.g3 Nf6, Black is planning to play ...Qh5 and aggressively capitalize on White's weak light squares. If White stops this with 27.Qd1, Black has 27...Bg4.

---
Tags: analysis, world-championship, fischer, spassky, 1972-world-championship
---


# Question
Title: How good of a tactical player is Magnus?
Everyone knows the amazing positional ability and endgame ability of Magnus Carlsen, but how is his tactical skills. I have heard someone say tactics are not his specialty? is this accurate

# Answer
You can't be a strong positional player without being a strong tactical player... and you can't be a strong tactical player without being a strong positional player. The two go hand in hand, and when a player is strong they tend to be strong in both domains. Here's one way of explaining this. In order to achieve a good position, you have to see the tactical possibilities on the board. This will let you find good squares for your pieces and activate them. And in order to have tactical possibilities, you need to achieve a good position, as tactics flow from a good position. That's why the two are connected. For someone of Magnus's strength (the best in the world) you have to be extremely strong in both. So, to answer your question, he is extremely strong at tactical chess, positional chess, and endgames.

Another question you might ask is, what is his style? Does he play tactically or positionally? A player's style is largely composed of the positions they have learned and the openings they choose. Historically Magnus has a positional style as he tends to play strategic positions over sharp, tactical ones. However, recently this has changed. In the World Championship against Caruana, he played one of the sharpest openings with black, the Sicilian Sveshnikov. In Tata Steel he reprised this opening. Thus it seems that he is favoring sharp openings with black these days, perhaps out of his desire to win more games and play fewer draws. It will be interesting to see how he plays during the rest of the year. Will he continue to play sharp, unbalanced openings with black? Will he continue to play aggressively with considerable risk? To draw a connection between this question and the one you asked, it's important to point out that Magnus can do this -- switch from a positional style to a sharper and more aggressive style -- because he is so strong both tactically and positionally.

Here is a masterful endgame he played in 2012 which showcases both strategy and tactics. Notice how 38. Kd5 involves a tactic that lets him improve his position, an example of how tactical and positional chess are connected. Another example would be 49. f6.

```
[fen ""]
[Event "Grand Slam Chess Final"]
[Site "Sao Paulo BRA"]
[Date "2012.10.08"]
[EventDate "2012.09.24"]
[Round "6"]
[Result "1-0"]
[White "Magnus Carlsen"]
[Black "Fabiano Caruana"]
[ECO "C00"]

1.e4 e6 2.d3 d5 3.Nd2 Nf6 4.Ngf3 Nc6 5.c3 Bd6 6.Be2 O-O 7.O-O a5 8.Re1 e5 9.exd5 Nxd5 10.Nc4 Re8 11.Bf1 Bg4 12.h3 Bh5 13.g3 Nb6 14.Nxb6 cxb6 15.Bg2 b5 16.a4 b4 17.Be3 Bc7 18.Qb3 h6 19.Qc4 bxc3 20.bxc3 e4 21.dxe4 Bxf3 22.Bxf3 Ne5 23.Qe2 Nxf3+ 24.Qxf3 Qd3 25.Kg2 Qxe4 26.Bd4 Qxf3+ 27.Kxf3 b6 28.Rab1 Rac8 29.Re4 g6 30.g4 Kf8 31.h4 Rxe4 32.Kxe4 Re8+ 33.Kd3 Re6 34.Be3 Kg7 35.Rb5 Bd8 36.h5 Rd6+ 37.Kc4 Rc6+ 38.Kd5 Re6 39.Bd4+ Kf8 40.f4 Bc7 41.f5 Rd6+ 42.Ke4 Rc6 43.Rb1 Ke8 44.hxg6 fxg6 45.Rh1 Kf7 46.Kd5 Rd6+ 47.Kc4 gxf5 48.gxf5 Bd8 49.f6 Bxf6 50.Rxh6 Be7 51.Rxd6 Bxd6 52.Kb5 Ke6 53.Bxb6 Kd7 54.c4 Kc8 55.Bxa5 Kb7 56.Bb4 Bf4 57.c5 Ka7 58.c6 Kb8 59.a5 Ka7 60.a6 Ka8 61.Bc5 Bb8 62.Kc4 Bc7 63.Kd5 Bd8 64.Ke6 Bc7 65.Kd7 Ba5 66.Be7 1-0

```

Here's a Sicilian he played as white against Karjakin in the 2016 tie break. He plays a strategic Maroczy bind in the opening but uses a clever tactic to win at the end.

```
[fen ""]
[Event "Carlsen - Karjakin World Championship Match"]
[Site "New York, NY USA"]
[Date "2016.11.30"]
[EventDate "2016.11.11"]
[Round "13.4"]
[Result "1-0"]
[White "Magnus Carlsen"]
[Black "Sergey Karjakin"]
[ECO "B54"]

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.f3 e5 6.Nb3 Be7 7.c4
a5 8.Be3 a4 9.Nc1 O-O 10.Nc3 Qa5 11.Qd2 Na6 12.Be2 Nc5 13.O-O
Bd7 14.Rb1 Rfc8 15.b4 axb3 16.axb3 Qd8 17.Nd3 Ne6 18.Nb4 Bc6
19.Rfd1 h5 20.Bf1 h4 21.Qf2 Nd7 22.g3 Ra3 23.Bh3 Rca8 24.Nc2
R3a6 25.Nb4 Ra5 26.Nc2 b6 27.Rd2 Qc7 28.Rbd1 Bf8 29.gxh4 Nf4
30.Bxf4 exf4 31.Bxd7 Qxd7 32.Nb4 Ra3 33.Nxc6 Qxc6 34.Nb5 Rxb3
35.Nd4 Qxc4 36.Nxb3 Qxb3 37.Qe2 Be7 38.Kg2 Qe6 39.h5 Ra3
40.Rd3 Ra2 41.R3d2 Ra3 42.Rd3 Ra7 43.Rd5 Rc7 44.Qd2 Qf6 45.Rf5
Qh4 46.Rc1 Ra7 47.Qxf4 Ra2+ 48.Kh1 Qf2 49.Rc8+ Kh7 50.Qh6+ 1-0

```

And here's a blitz game he played in 2015. A lot of these moves, including the tactical blows at the end, he played almost instantly. Notice how 19... Bf5 20. Qd2 would lose to 20... Be4 with an unstoppable mate. In a blitz game it's very hard to respond to a move like 19... Bf5. Everything goes downhill after 20. e4 Qxd3. And 24... Bb4 followed by 25... Bd3 is a clever way of saving material after 24. Rd2 put both bishops in a skewer.

```
[fen ""]
[Event "banter blitz"]
[Site "chess24.com"]
[Date "2015.11.??"]
[EventDate "2017.??.??"]
[Round "?"]
[Result "0-1"]
[White "Jan Gustafsson"]
[Black "Magnus Carlsen"]
[ECO "A96"]

1.Nf3 f5 2.g3 Nf6 3.Bg2 e6 4.O-O Be7 5.c4 O-O 6.Nc3 d6 7.d4 a5
8.b3 Qe8 9.Ba3 Na6 10.Rc1 Nb4 11.Qd2 Ne4 12.Nxe4 fxe4 13.Ne1
Qg6 14.Nc2 Bg5 15.e3 Nd3 16.Rcd1 e5 17.Bxe4 Qxe4 18.Qxd3 Qf3
19.dxe5 Bf5 20.e4 Qxd3 21.Rxd3 Bxe4 22.Rc3 Bd2 23.Re3 Bxc2
24.Re2 Bb4 25.Bxb4 Bd3 0-1

```
> 3 votes

# Answer
He's definitely one of the most tactically skilled players on the planet. Arguably not the #1 tactical player, but he's definitely up there in the highest echelon.

He's more known for his endgame abilities, but that doesn't mean that he's lacking tactically. He wouldn't be able to gain and retain the world championship title for 6 years if he was.
> 0 votes

---
Tags: tactics, positional-play
---


# Question
Title: Professional Databases and Historical Games
I have tried to look for historical chess games (i.e. 19th century to early 20th century). I usually use Chessbase online database and `chessgames.com`.

I have never paid for a database or database subscription, but I was wondering if anyone knows whether they tend to have more complete historical games than the free options available on these chess websites?

# Answer
> 1 votes
Have you looked at https://chess-db.com/public/index.jsp

This website has historical players like: Morphy, Marshall, Steinitz, Bird. You can download all their games.

---
Tags: history, database
---


# Question
Title: Rook and bishop vs. opposite color bishop
I drew a game with rook and bishop vs an opposite color bishop due to the 50-move rule.

```
[FEN "4b3/k1B5/8/2K5/8/8/R7/8 w - - 0 1"]

```

Is this a theoretical draw? If not, what is the technique to win?

# Answer
Definitely not a theoretical draw, this should be easily winning for White. The strategy to win would be:

* Advance with your king and rook to push back Black's king. If Black's light-squared bishop blocks your rook's check, then this means the Black king is on a dark square. Thus, you can use your dark-squared bishop to check the king and push it back.
* Eventually you'll have pushed Black's king to either a light-squared or dark-squared corner.

+ If it's in a light-squared corner like a8, the light-squared bishop isn't able to act as a blockader from your rook. In the diagram you posted, here's one example of how to win: 1...Kb7 2.Bb6 Bh5 3.Ra7+ Kb8 4.Kd6 Bf3 5.Rc7 Bg2 6.Ba7+ Ka8 7.Kc5 Bf3 8.Kb6. Now all you need to do is maneuver your rook to the 8th rank to checkmate, which can be accomplished in as little as 2 moves.
    + If it's in a dark-squared corner like h8: Put your king on h6 and move your rook to the 8th rank, checking the Black king. If Black manages to block the check with ...Bg8, then you can checkmate immediately by moving your bishop onto the a1-h8 diagonal.
> 10 votes

# Answer
I don't know about the technique beyond trying to keep all your pieces on the dark squares and the enemy king cornered, but the position above is not a draw. According to the endgame tablebase it's mate in 10 moves. Here's one line:

```
[FEN "4b3/k1B5/8/2K5/8/8/R7/8 b - - 0 1"]

1... Kb7 2. Ba5 Bg6 3. Rb2+ Ka7 4. Rb6 Bc2 5. Kd6
Bd1 6. Kc7 Bc2 7. Bc3 Be4 8. Bd4 Bb7 9. Rd6+
Ka8 10. Rd8+ Bc8 11. Rxc8#

```

If you want statistics more generally, see http://www.maths.usyd.edu.au/u/thiel/misc/endgames/ . According to the table, for KRB vs KB, with white to move, 98.2% of positions are won by white and 1.8% are drawn; with black to move, 31.1% are drawn. Note that this table doesn't make the distinction between same-colored and opposite-colored bishops. The draws are probably positions where white loses the rook in the next move or two.
> 2 votes

---
Tags: analysis, rook-and-minor-endgame
---


title: Most complicated mode for chess engines

text:
# Question
Title: Most complicated mode for chess engines
I have used many chess engines, especially Stockfish and I want to ask you, if it possible to change its mode to the most complicated one. What I mean:

Now, most engines work as following: 1) Mate the opponent asap. 2) If it is not possible to mate him, then draw him asap. 3) If it is not possible to draw him, then delay its mate as longer as you can.

Or something similar, I don't know. So my question is if it can change, so anytime engine will choose this move that makes the game as complicated as possible.

An example: Imagine we are in a position that engine can choose two moves: A or B.

The A one, is the best defense and if the opponent is engine can mate us in minimum 30 moves. But also the win by a simple human of 2000 Elo is possible. Just applying simple theory. In 50-60 moves, human also can mate.

The B one is not good, an engine can mate us in 10 moves but this combination of 10 moves is completely unique and it is very difficult to be seen by a human, neither by Carlsen. If a mistake will be done, then we will win the opponent.

Simply said, the first move is the best one if the engine plays against an engine because it delays the mate much, but if it plays against a human it is very simple to lose. The second move is bad if the engine plays against an engine because it can be mated in 10 moves, but if it plays against a human, even against Carlsen, it is a bluff move, because this combination of the next 10 moves is completely invisible by humans and a mistake is 100% sure to be done, so engine will win human.

Is it possible to change this mode in engines? Or can an engine detect whether it plays against engine or human and adjust its moves? So if it loses and plays against human, it can choose the most complicated moves, hoping for a human-blundering...?

# Answer
> 3 votes
You are talking about playing suboptimal moves for bluffing. Stockfish is not good at that... Chess programming theories are no good because it’s hard to define a complicated position. There were research articles on this topic but it’s still an unsolved problem.

I believe you will need a good mathematics model. Stockfish doesn’t have it.

# Answer
> 0 votes
This is definitely not possible in Stockfish. An engine like Stockfish plays the moves it would play against an engine, not a human. To get an engine playing with a human reasoning is very difficult due to the fact that the engine would have to determine how "human" every line is. You need a human brain to determine how complicated a specific variation is to a human.

The best you could try to get human play is to install an engine running on neural networks (LeelaChess being a good example) by using the neural network that enables the engine to play at an approximate ELO of the human you would like to simulate. Even this won't result in 100% human play.

---
Tags: engines, stockfish, human-versus-machine
---


# Question
Title: Why does NN + MCTS & AB + handwritten eval dominate engine chess?
As I understand it engines can be divided into four groups right now: those that use Alpha-beta (AB) + those that use Monte Carlo Tree Search (MCTS) for search, and those that use handwritten functions + those that use neural networks for eval. The two strongest engines are Leela and Stockfish. Leela uses MCTS + NN, while Stockfish uses AB + handwritten.

Why these two combinations? Why not NN + AB, or MCTS + handwritten? If MCTS is better than AB, why isn't Komodo MCTS stronger than Komodo AB? If AB is better than MCTS, why isn't Leela using AB instead?

**Edit:** for anyone who sees this question today (2023), it is **outdated**, because Stockfish uses NNUE evaluation these days instead of its handcrafted eval, and top engines are NN + MCTS & AB + "NN".

# Answer
## Speed

Neural networks operate much more slowly than handcrafted evaluation functions. In the TCEC Superfinal, Leela Chess Zero, running on two GPUs each with dedicated tensor cores, is able to search around 60 thousand positions per second. By contrast, Stockfish, on a single core on my PC, searches over 2 million positions per second.

While modern engines have a huge selection of techniques to cut off unnecessary branches, alpha-beta tree search is still very much a brute force technique, requiring vast numbers of positions to be searched to determine good moves.

MCTS, by contrast, is far more selective, and only expands its search tree towards the most promising moves, which allows it to make the most of the more limited number of nodes that can be searched.

## Worst-case behaviour

One of the key requirements of the evaluation function for an engine based around alpha-beta search is that it must have good worst-case behaviour. This is because any large error in evaluation, however rare, can easily be propagated to the root and lead to a horrendously incorrect move being played.

By nature of their complexity, neural networks are prone to overfitting and can only be as good as the data used to train them. For example, in match 80 of the TCEC Season 14 Superfinal, on move 47 Lc0 was apparently unfazed by Stockfish's extra queen, evaluating the position as a cool +0.77, while Stockfish (and most other engines) sported an evaluation of +8.31. A popular explanation for this is that Lc0 may not have had a significant number of games with multiple queens on the board in its training set.

Neural networks, therefore, have poor worst-case behaviour, and hence are likely to perform poorly with alpha beta search. MCTS, by contrast, allows an incorrect score assigned to one position to be offset by averaging it out with reasonable scores assigned to positions nearby in the search.

## Quiescence

All strong alpha-beta engines use a technique called quiescence search, a restricted form of alpha-beta search applied at leaf nodes, in acknowledgement that their handcrafted evaluation functions only work well in "quiet" positions, where there are no pending captures or checks.

For example, immediately after the first half of a queen exchange, a handcrafted evaluation function might tell you that the side which just had their queen taken is completely lost, whereas a neural network may be able to understand that the queen will be recaptured soon.

This makes handcrafted evaluation functions similarly unsuitable for MCTS due to absence of quiescence search, resulting in the handcrafted functions performing poorly much of the time (although Komodo 12 MCTS gets around this restriction by using short alpha-beta searches anyway, to get quiescent positions and hence allow its handcrafted evaluation to return a reasonable score)
> 16 votes

# Answer
AB and MCTS aren't necessarily better than each other on their own merits. It's just that they are different search algorithms that work better with different foundations. For the NN, MCTS works well since it allows the engine to explore branches that are doing better. This gives the engine more freedom to look at what it "wants" to.

Meanwhile with AB, all branches in principle have to be looked at. This is because even with iterative deepening, the engine only looks so far on each branch in each iteration. So it doesn't know if one branch is actually winning for one side, even if it seems losing at a limited depth.
> 2 votes

---
Tags: engines
---


title: Setting up the knights

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

# Answer
There is nothing in the rules about this.

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

Here is an image from the world chess championship:

Carlsen has placed his knights facing each other, and Caruana has positioned his knights facing forwards.
> 4 votes

# Answer
The rules say nothing about this, and it varies from person to person (including among professionals). Some people place their knights facing sideways and forwards, and another popular orientation is placing them in a diagonal pointed towards the centre.

You could place them pointing backwards if you want to screw with your opponent, but I've never seen someone do this in an actual game.
> 2 votes

---
Tags: knights
---


title: What did I blunder at move 23?

text:
# Question
Title: What did I blunder at move 23?
I played a game recently on chess.com, where the most detailed analysis identified a single blunder in the game -- 23. d6 The analysis given by the computer suggested that 23 Qd1 was better, with the line it gave then chasing the black knight around the board until it was captured, and freeing the Black queen rook in the process.

Myself and my opponent both like 23. d6 (well, I liked it more than he did) as it locks out the entire Black queenside for the rest of the game. From my perspective I'm a rook and bishop up at this point, which makes it hard to me to see this as a blunder.

Could anyone perhaps point out better reasons why I should regard this move as a blunder?

```
[fen ""]
[Event "Let's Play!"]
[Site "Chess.com"]
[Date "2019.02.19"]
[Round "-"]
[White "postmortes"]
[Black "Glebbf"]
[Result "1-0"]
[WhiteElo "1341"]
[BlackElo "859"]
[TimeControl "1/86400"]
[EndDate "2019.02.21"]
[Termination "postmortes won by checkmate"]

1. g3 e5 2. Bg2 Nf6 3. Nc3 Bd6 4. e3 Na6 5. Nge2 O-O 6. O-O c6 7. a3 Qc7 8. b4
Re8 9. d3 c5 10. Re1 h5 11. b5 Nb8 12. Rb1 Re6 13. Bd2 c4 14. a4 cxd3 15. cxd3
a6 16. b6 Qc5 17. d4 exd4 18. exd4 Qf5 19. Nf4 Bxf4 20. Bxf4 Nc6 21. d5 Rxe1+
22. Qxe1 Nd4 23. d6 h4 24. Ne4 h3 25. Nxf6+ Qxf6 26. Qe8+ Kh7 27. Be4+ Nf5 28.
Qe7 Qg6 29. Qe5 Kg8 30. Bxf5 f6 31. Qd5+ Qf7 32. Qxf7+ Kxf7 33. a5 g6 34. Bxh3
f5 35. Re1 Kf6 36. Bf1 Kf7 37. Bc4+ Kf6 38. h4 Kg7 39. Re7+ Kf8 40. Bh6# 1-0

```

# Answer
> 7 votes
This may be the horizon effect at work.

I analyzed the position a bit with Lichess' Stockfish, which at depth ~20 likes 23. Rd1 (+8.0~8.5) even more than 23. Qd1 (+7.0~7.5). The idea is the same: White catches Black's knight, for an immediate material advantage (e.g. 23. Qd1 Nc2 24. Rb2 Na3 25. Qb3).

After 23. d6 on the other hand, Stockfish still gives a solid advantage of +4.0~5.0 (no human would call that "blunder" since it's still clearly winning) at depth ~20, but the following lines are rather unforcing.

A likely explanation is that in either variation there are so many defensive possibilites left (there's a lot of open space to manoeuvre!) that Stockfish is unable to find a concrete way to force mate or even only increase White's advantage substantially within its search horizon. It does of course realize that White has the much better position, which it prices at around +5.0~6.0, but that's it. In the Qd1/Rd1 line, it then simply adds the material advantage of +2.0~3.0 of that missing knight. However, it won't do the same for the queenside rook and bishop in the d6 line since it has no way to tell that these pieces are buried forever (that would require it to go deeper in its search). The engine cannot exclude that these pieces will become active again at depth 50 or something, so it still counts them in. We as humans do of course know better (one of the last cases we do).

Case in point: While writing this, the evaluation of 23. d6 increased to +6.5 at depth 30. It will most likely converge with the one of 23. Qd1 / 23. Rd1 at some point.

**From a human point of view, you should not view this move as a blunder.**

---

Update:

Depth 32 starting from the position after 22...Nd4:

```
1 23. Rd1 +8.4
2 23. Qd1 +7.7
3 23. Qe3 +7.1
4 23. d6 +6.9
5 ...

```

We're getting closer.

# Answer
> 2 votes
I wouldn't call your move a blunder, it seems just as good as winning the Black knight. Stockfish puts you at roughly +2.5 with 23.d6, while winning the knight with 23.Qd1 yields roughly +5.5. Honestly not such a huge difference - at such extreme evaluations you should generally prefer the move that's easier to play.

It's easier for engines to evaluate being a clean piece up, rather than a few of your opponent's pieces being indefinitely trapped. This is a well known flaw in the top well known engines (Stockfish, Komodo, Houdini, etc). They're very good at searching, but their evaluation functions aren't perfect.

---
Tags: analysis, beginner
---


# Question
Title: Does 40/100, SD/30 d10 mean that the delay is applied to both time controls?
I am going to be going to my first tournament soon (the southern class championship), and am slightly confused about the time control. Most tournament listings have something along the lines of 40/100, SD/30, d10 which makes it obvious that the 10 second delay applies to both time controls. However, the listing for the tournament says 40/100, SD/30 d10. The lack of comma makes me think that possibly this delay only applies to the second time control. Is this something I should ask the director about, or is this just another way to write a delay that applies to both time controls?

# Answer
> 3 votes
It looks like the tournament is run by the Continental Chess Association. From my experience playing in many CCA tournaments, the d10 is applied to both time controls.

# Answer
> 1 votes
The standard setting is for the delay to be applied to both time controls. I haven't heard of a tournament that has only applied the delay to one of the time controls. So it should be safe to assume the delay is enduring throughout the whole game, but it never hurts to ask the TD just in case.

---
Tags: tournament, time-control
---


title: How does "go mate <x>" work in UCI

text:
# Question
Title: How does "go mate <x>" work in UCI
In the UCI documentation, it says

> * mate x
>
> search for a mate in x moves

However, I believe this should say "search for mate in x plies", as plies are used in most of the protocol. I can not find any good documentation for this. Which way does it actually work?

# Answer
> 1 votes
The specification is correct here.

An appropriate implementation would start a search, and then terminate it once a checkmate has been found in `x` full moves, or `2x` plies

> I believe this should say "search for mate in x plies", as plies are used in most of the protocol.

This is not the case.

The way that mate scores are handled is one of the quirks of the UCI Protocol. As it happens, using full moves to describe mates **is consistent** with the rest of the protocol.

For example, here is the section which describes how scores should be reported:

```
* score
    * cp <x>
        the score from the engine's point of view in centipawns.
    * mate <y>
        mate in y moves, not plies.
        If the engine is getting mated use negative values for y.

```

Here, the mate scores must also be reported in full moves, just like the requirement for `go mate <x>`.

You are, however, right to find this unusual, as most chess engines do represent mate scores in plies internally.

---
Tags: uci
---


# Question
Title: How do I register for a tournament that appears in the FIDE website but not on chess-results?
Here is this tournament on the FIDE website. However, there are no contact details, no venue mentioned and the tournament does not appear in the chess-results database. How do I register for such a tournament?

# Answer
FIDE used to publish contact details for arbiters but they no longer do so. However if you can look up any of the three mentioned arbiters and find contact details locally that would be your quickest route.

Failing that your next best bet would be to contact the Sudan Chess Federation. There the email address is given as sudanchessfed@yahoo.com and the phone number as +249916177000. Additional (different) phone numbers are given for the president and two vice presidents. You could also try these.
> 3 votes

---
Tags: tournament
---


title: Chess FEN winner

text:
# Question
Title: Chess FEN winner
I'm new to Chess FEN notation and I'm making an online chess game, but I have one problem, I need to check after every new move if there is a winner and which one is a winner.

Can I extract that information from FEN notation ?

# Answer
> 3 votes
FEN (Forsyth-Edwards Notation) is a way of recording the current position on the chess board - piece positions, active colour, castling possibilities, en passant target, half move clock, full move number. The result of the game is not included.

---
Tags: online-chess, fen, winning
---


# Question
Title: What's the winning box for the King in a Queen against 7th rank Bishop-pawn endgame?
In a Queen vs Pawn endgame where the pawn is a Rook pawn on the 7th rank, it is a draw unless the King is inside the winning box, as shown here:

My question is what is that winning box if the pawn is a Bishop pawn? Though I do know that the Queen needs to be on h2 or d2 against an f pawn, and on a2 or e2 against a c pawn. (Comparing to the whole 2nd rank if it was a Rook pawn).

# Answer
> 10 votes
There are actually *two* zones, depending on which side of the pawn the black king is. If it's already in the corner, the zone is small:

If the black king on the other side (towards the center), the zone is larger. The white queen can force the king to stand in front of the pawn, giving the white king an extra tempo to reach the 'small' zone above. (This also applies if the king is in front of the pawn already.)

<sub>(diagrams from Fundamental Chess Endings by Müller and Lamprecht)</sub>

# Answer
> 5 votes
This is given by Karsten Muller for Chessbase.

---
Tags: endgame, queen-endgame
---


# Question
Title: Can the book 'Grand master Preparation: Calulation' by Aagard be useful for a Class B chess players?
I heard in most chess forums this book is for 2400+. Can this book also be useful for Class B players? I'm looking for a book to improve my calculation and planning. If so, in what ways? What would be the best way to self-study this book as a Class B?

# Answer
> 3 votes
I'm rated around 2150 Elo and I used the book two years ago, to solve exercises on the way to work. I could solve approximately 50%, which felt somewhat disheartening, though objectively, I guess, it's pretty ok for my level. I definitely profited from the training.

I wouldn't recommend the book for players significantly weaker than me. Mostly because it's demotivating if you are always struggling to even think in the right direction. I have found that the final instalment of the Yusupov series fits my own level better (i.e. tough but solvable).

But if you can keep your motivation up, even without much positive feedback, of course you can profit from thinking deeply about just about any position.

# Answer
> 1 votes
For a B-player, or any non-master for that matter, the problem with this book is that the examples and study positions are complex and will be difficult for an amateur to understand and analyze. Nevertheless, the concepts in the book and techniques are completely valid and useful for a B-player.

To make best use of a book like this, I would recommend learning the ideas and concepts in the book and then applying them to easier examples which you can find in intermediate-level books. So, look at Aagard's examples, but when you actually go to train use easier positions.

# Answer
> -2 votes
I've read 60 Memorable Games by Fischer, Art of Attack by Vukovic, Understanding Chess: Move by Move by Nunn, and My System by Nimzowitsch.

These books got me to ~1800, but something was missing.

Before the end of 2018, in December, IM Alejandro Moreno recommended Chess Praxis.

"Another book?" I thought. Weary and withered, I reluctantly read the book. I really felt like a law student at this point (mind you, I was studying chess in a quiet area of the law library - with the rollable board and wooden pieces).

I've read Chess Praxis. Here's where it's gotten me:

(Note the highest rating in October - that was when I finished reading the three books listed at the beginning of this post, minus Nimzowitsch. I was playing sharp, but my positional play was unsound. So once I got bored of the lines, I dropped down to ~1700 (!) in a week).

And in my last USCF Tournament (2/16/19), I scored 2.5/4.0 in the open, beat an expert, drew a National Master, and took a 1900 to the cleaners. My rating exploded from 1815 -\> 1880.

If there's one book you must read, it's Chess Praxis.

Reading those five books only took three months, but those will be the three most critical months of your life.

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Tags: books, training
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# Question
Title: What is the draw frequency for 3 consecutive games (same players; amateur level)?
In Mr. Robot (TV series) episode "eps2.2\_init\_1.asec", Elliot and Mr. Robot drew 3 consecutive chess games. They remark it's impossible.

> The odds of that are Impossible.

As far as TV shows go, Mr. Robot is known for its technical accuracy. I was surprised when I heard that line, so I fact-checked it:

From Wikipedia:

> \[Frequency of draws\] is currently "holding pretty steady around 50%, and is only increasing at a very slow rate".

I understand that figure is for top-level tournaments, not 3 consecutive games from the same 2 players. Is there are any accuracy to that statement in the show? If not, is it different from the 50% rate for top-level players?

# Answer
> 9 votes
Definitely not impossible! It is true that draws are less frequent in amateur chess, and it is also true that draws are less frequent for faster games (how fast was the game in the show?), but even so, let's say that for a blitz game between evenly matched amateurs the draw frequency were 5%, or 1/20. If you played three games, the odds of playing three draws would be 1/8000, which while unlikely, is hardly "impossible". This is assuming that the probabilities are independent, which may not be entirely true but I think is close enough for a rough estimate.

I don't have an academic citation, but if you want some stats for online games you can look at the Lichess opening book: https://lichess.org/analysis . Normally it shows master-level games, but if you click on the settings you can chose to look at Lichess games instead, and filter by rating and time control. For blitz games at rating 1600, the draw frequency is 4-5%, depending on the opening move (the draw is the small gray stripe without a percentage, so you have to compute it by difference):

For the highest ratings, it's closer to 10% for blitz. And for classical chess, as you know, it's about 50% for top-level chess. For amateur chess I'd say maybe 10-20% but it depends on which level of amateur we are talking about. I won't cite the Lichess stats here because even though they have a "classical" category, it's really what would called rapid in over-the-board tournaments (30 min games in Lichess; OTB classical is usually 2 hours or more).

# Answer
> 3 votes
From a transcript at https://www.springfieldspringfield.co.uk/view\_episode\_scripts.php?tv-show=mr-robot-2015&episode=s02e04

> You just need to be able to see ahead of your opponent.
>
> But how can you when your other opponent is you? **Stalemate**.
>
> Three in a row.
>
> The odds of that are Impossible.

So the impossibility mentioned can be interpreted to be three stalemates in a row, not simply three draws. I could not quickly find a reference to the stalemate rate, but it must be significantly less than the draw rate, and the cube of it will therefore tend a bit closer to "impossible".

I don't know if the moves in the show are meant to be real games or just a nod to the audience that is looking closely (kind of like the in-jokes written in tiny print on "Star Trek" displays). But the first two are reported to be the Loyd 10-move stalemate and the final game is Minerva's fastest known double stalemate. (I don't have a copy of the video to confirm this)

Because they are "constructed" puzzles, neither would be expected in a competitive game, only a cooperation scenario. That may or may not mean something in the context of the episode.

# Answer
> 2 votes
As standard math says, probability of *same* event happening in a row for `N` times is:

> PeN

where Pe is single event probability.

So if we take as standard draw probability 50%, then event of having 3 draws in a row between some players will be 1/23 = 0,125 = `12.5%`. Thus not impossible, but **unlikely**.

However there can be specific pairs of players which always plays at optimal strategy for each-other, so that their games mostly ends in a draw.

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Tags: draw, statistics
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# Question
Title: Not Developing a Piece in the First Five Moves
Here are the first few moves:

1.c4 e5 2.Nc3 Bb4 3.Nd5 Bc5 4.Nf3 e4 5.d4 Bf8

After the fifth move, black has essentially only pushed one pawn, while while has developed two knights and his c-pawn and d-pawn. However, the current position does not seem bad for black at all. 365chess.com gives winnings percentage White / Draw / Black as 25% /50% /25%.

```
[fen ""]
1.c4 e5 2.Nc3 Bb4 3.Nd5 Bc5 4.Nf3 e4 5.d4 Bf8

```

My question is, in the first few moves, has black violated any opening principles? Why this position is not too bad for black while he has only pushed one pawn while white has developed two nights (and it is white's turn now)?

# Answer
Obviously black has violated principles such as:

* don't move a piece twice
* develop pieces

However opening principles are just general guidelines and in very concrete positions like the one at hand they are of little use. There are many established openings where opening principles are broken, so nothing wrong with that.

In the final position it is white's move, however the knight on f3 is attacked and has to move. After the knight has moved, black will most certainly kick away the other knight by playing c6 and then create a strong pawn center with d5 or f5.

White has currently a lead in development but black has more space and will have an easier development for its minor pieces than white. If there is nothing immediately threatening from white, I don't see why black should have a bad position.

Note that my engine still prefers white's position by about +0.5.
> 12 votes

# Answer
In their recent book The Modern English 1.c4 e5, GM Kiril Georgiev and Semko Semkov consider the line 1.c4 e5 2.Nc3 Bb4 3.Nd5 (considered better than 3.Qc2) Bc5 (the alternative is 3...a5) 4.Nf3 e4, although their main variation continues with 4...c6.

They now recommend 5.Ng5! because

> 5.d4 is also possible, but after 5...Be7 we cannot put the knight on g5.

In the game you consider, Black obviously anti-developed with 5...Bf8?! (which indeed goes against the main opening principle) because he was afraid of losing the bishop pair after 5...Be7 6.Ne7. However, after a further 6...Qe7 7.Nd4 Nf6 (or even Qc5 8.e3 Nf6), Black's faster development and space advantage likely compensate for the bishops.

On the other hand, 5...Bf8 6.Bf4 d6 7.Ng5 or 7.Nd2 yields a nice initiative to White.
> 1 votes

# Answer
The first moves look, by Black and White like a "Sicilian with reversed colors!" (Before Bb4) For Black I would prefer Nf6 (rather than Bb4)

After Bb4, I would move Qc2, (rather than Nd5) then a3

1) In the opening The first plan is "sound development", prepare for a possible castling, as soon as possible.

2) A "premature attack", usually means a lose of time (tempo), which is dangerous in the opening phase!
> -1 votes

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Tags: opening, english-opening, development
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