# Question
Title: In the Delayed Open Catalan, what is the best move after 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8?
I'm building my White repertoire.

After 1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8 we reach the following position:

```
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8

```

My question is: which move should I choose?

* 10. Qc2
* 10. Qb3
* 10. Qa4

What are the advantages and disadvantages of each one of them?

I would like to choose the move which (on average) leads to the most positional, solid, quiet and strategic positions (not sharp and tactical positions).

There are only 6 games which reached this position in my opening database: White played 10. Qc2 in 3 of them, and White played 10. Qb3 in the other 3 of them.

Komodo 8 says after a depth of 26 plies (2 hours):

* 10. Qc2 : +0.22
* 10. Qb3 : +0.36
* 10. Qa4 : +0.37

Stockfish 5 says after a depth of 31 plies (1 hour):

* 10. Qc2 : +0.18
* 10. Qb3 : +0.32
* 10. Qa4 : +0.32

Gull 3 says after a depth of 25 plies (5 hours):

* 10. Qc2 : +0.00
* 10. Qb3 : +0.30
* 10. Qa4 : +0.22

# Answer
> 3 votes
I play the Catalan in a constant basis, and in this position I would play Qb3 for the following reasons:

* 10.Qa4 =\> does not look that great because at any moment black can play Bd7 (gaining a tempo on the queen) and then Bc6, and thus, releasing some of the pressure in the light squares of the queenside.

Line:

```
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8 10. Qa4 Bd7 11. Qb4 Bc6

```

---

* 10.Qc2 =\> leave the queen "tactically vulnerable" and, in some lines, disconnect the queen from the knight in c4 (after Nc3, for instance). Two SAMPLES lines to consider:

Example 01:

```
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8 10. Qc2 Bxc5 11. Nc3 Bxf2+ 12. Rxf2 Qxc4

```

Example 02:

```
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Ne5 c5 8. dxc5 Qc7 9. Nxc4 Rd8 10. Qc2 Bxc5 11. h3 b5 12. Ncd2 Bxf2+ 13. Rxf2 Qxc2

```

I'm not saying in any way, shape or form that these lines are good, I'm just trying to point out the tactical themes that could arise from such positions.

---

* 10.Qb3 =\> There is no tempo gaining move on the queen. The knight on c4 would be protected even after the natural move Nc3. And you keep the pressure on b7.

The three moves are good but if you want a quiet, positional game but maintaining long term pressure I would recommend Qb3. The other 2 keep some dynamism in the position and could bring complications in the long run.

---
Tags: opening, theory, strategy, positional-play, catalan
---


# Question
Title: Rule enforcing a player to move on a turn?
I'm an amateur chess enthusiastic and I have a somewhat esoteric question about the rules of moving on a turn. In chess, is there a specified rule that a player *must* move a piece during her turn?

I realize that in a chess game, there is no reason to not move a piece. But I'm designing puzzles relating t o chess and whether this rule exists matters for the puzzle.

# Answer
> 6 votes
Yes, there is a rule that a player must make a move during her turn. If the player in turn has no legal moves and her king is not in check, then the game is drawn.

> I realize that in a chess game, there is no reason to not move a piece.

Actually, almost *all chess endgame theory*, and thus *a huge part of the whole game of chess is based on the fact that a player has to move a piece during her turn*. I'll explain this by a simple example and some handwawing. Consider for example the following endgame:

```
[title "White to move and win"]
[fen "4k3/8/4K3/4P3/8/8/8/8 w - - 0 1"]

1. Kf6 Kf8 2. e6 Ke8 3. e7 Kd7 4. Kf7 Kd6 5. e8=Q

```

If, at her 4th move, Black didn't have to move the king, the game would be drawn, as there is no way for White to promote her pawn. However, because Black king has to step away, White gets a new queen and wins the game. (Note that this does not mean that a king and a pawn always win against a lone king; very often the game will be drawn, because also White has to make moves she would not want to make.) A situation like this, where having the turn actually makes your position significantly weaker, is called a *zugzwang*; for more examples, see for example the Wikipedia article

This and more complex endgames are the reason why one pawn advantage is often enough to win: You can exchange pieces until you get to an endgame where you can then often convert the extra pawn to a win. Very often the winning technique of king and pawn endgames are based on the fact that the winning side can force the losing side's king to step away from defending important squares simply because the king cannot stay on the best square forever. The winning technique of many other endgames is then based on the fact that the winning side can threaten to convert to a winning king and pawn endgame, restricting the options the losing side has.

---
Tags: learning, rules
---


title: Sicilian with 1.e4 c5 2.c3 d5 3.Nf3?

text:
# Question
Title: Sicilian with 1.e4 c5 2.c3 d5 3.Nf3?
I don't know much "Sicilian" theory, and decided to develop instead to defend e4. My opponent captured, and I got the pawn back with the obvious Qa4 check. Although he tried to start a queen hunt, she was never in real danger, but quite annoying for black. After finally pushing to d4 I had a fine play and managed to win. I couldn't find anything about this line, so I guess there must be serious drawbacks, and so I'd like to see a refutation.

```
[FEN ""]
1.e4 c5 2.c3 d5 3.Nf3 dxe4 4.Qa4+ Bd7 5. Qxe4 Bc6 6. Qf4

```

# Answer
> 5 votes
Black has a small advantage in your position, but it's certainly not unplayable for white. Stockfish rates the position you've given around -0.2, which is pretty close to even. If black plays well it seems difficult for white to get a good d4 break, though if black tries too hard to chase the queen perhaps white will be able to get back the advantage. The main problem seems to be that the pawn on c3 is counterproductive: white can't play d4 with advantage and the pawn on c3 interferes with white's queenside development.

Stockfish suggests the following line, where black retains a small advantage (around -0.3)

```
[FEN ""]
1.e4 c5 2.c3 d5 3.Nf3 dxe4 4.Qa4+ Bd7 5. Qxe4 Bc6 6. Qf4 e6 7.Na3 Bd6 8.Qg4 Ne7 9.Nc4 O-O 10.Nxd6 Qxd6 11.Be2 e5 12.d3 Nd7 13.O-O Rfe8

```

Black is somewhat better off playing Nc6 on the 4th or 5th moves instead of occupying that square with the bishop. White is still fine, but should avoid 4. ... Nc6 5. Qxe5 and instead play 5. Ne5.

```
[FEN ""]
1.e4 c5 2.c3 d5 3.Nf3 dxe4 4.Qa4+ Nc6 5.Ne5 (5.Qxe4 Nf6 6.Qc2 a6 7.d3 e5 8.Nbd2 Be7 9.Nc4 Qc7 10.Be2 O-O 11.O-O Nd5 ) Bd7 6.Nxd7 Qxd7 7.Qxe4 Nf6 8.Qf3 e6

```

# Answer
> -1 votes
```
[FEN ""]

1. e4 c5 2. c3 d5 3. Nf3 dxe4 4. Qa4+ Nd7 5. Qxe4 Ngf6 6. Qc2 e5 7. d4 exd4
8. Bg5 Qe7+ 9. Be2 Ne5 10. O-O Nxf3+ 11. Bxf3 Be6 12. Re1 O-O-O 13. Qa4 a6
14. cxd4 Rxd4 15. Qc2 Qc7 16. Nc3 Ng4 17. Bxg4 Rxg4 18. Be3 Qc6 19. g3 Bd6
20. Ne2 f6 21. Rac1 c4 22. Nd4 Qd5 23. Nxe6 Qxe6 24. b3 Bb4 25. Re2 b5 26.
Bf4 Qd5 27. Rd1 Qf3 28. Qf5+ Kb7 29. Qd7+ Ka8 30. Re8+ Rxe8 31. Qxe8+ Kb7
32. Rd7+ Kb6 33. Qe6+ Bd6 34. Qxd6+ Ka5 35. Bd2+ c3 36. Qc7+ Kb4 37. Qd6+
Ka5 38. Be3 Rxg3+ 39. hxg3 Qxe3 40. fxe3 c2 41. Qa3+ Kb6 42. Qc1 Kc6 43.
Rxg7 h6 44. Qxc2+ Kd6 45. Qc7+ Kd5 46. Rd7+ Ke6 47. Qd6+ Kf5 48. Re7 Kg6
49. Qe6 h5 50. Qe4+ Kg5 51. Qf4+ Kg6 52. g4 hxg4 53. Qxg4+ Kh6 54. Rg7 f5
55. Qg6# 1-0

```

---
Tags: opening, theory, sicilian-defense
---


title: Common sacrifice themes in attacks?

text:
# Question
Title: Common sacrifice themes in attacks?
What are common sacrifical themes in mating attacks? For example, the Greek Bishop Sacrifice.

# Answer
> 5 votes
Not exactly sure what you're after with that question, but here's something to at least open the ground a little.

The "Greek Gift" I think is more a name for a particular sacrifice than a theme. It employs a couple of themes, e.g., line clearance and decoy -- line clearance opens a hole in the castled position for other pieces to use for attacks, and decoy brings the enemy king to a square where it can more easily be attacked. Another famous sacrifice using those themes is Lasker-Bauer (Lasker's double bishop sacrifice).

There are numerous resources covering tactical themes, going back to Spielmann's "The Art of Sacrifice In Chess" but a couple of the best resources for mating themes and patterns are Renaud & Kahn's "Art Of The Checkmate" and Vukovic's "The Art of Attack in Chess" (of the two I'd prefer the latter only because it covers more than just checkmates, but all three books are well worth the time to study them).

In Vukovic's book, chapters 4 & 5 deal in general with your question of checkmating themes. As for the "Greek Gift" itself, he spends chapter 6 specifically on that sacrifice. Eugene Znosko-Borovsky in "The Art of Chess Combination" spends a chapter on it (and another on Lasker's double-bishop sacrifice) and Former US Correspondence Champion Jon Edwards devoted an entire book to it (Sacking The Citadel).

---
Tags: checkmate, sacrifice, greek-gift
---


# Question
Title: What are some methods that tournaments use to limit draws?
There has been a rising faction of chess players who believe that professional chess is too drawish. What are some ways that tournaments fight against the prevalence of draws?

# Answer
> 2 votes
The problem with chess having a large number of draws cannot itself be solved - it is simply a result of the defensive possibilities in many systems and the fact that high-level play reduces the number of losses due to simple mistakes. Without a fundamental change to the rules of chess this is not likely to change.

There have been several measures to prevent top players from agreeing to draws before the positions are completely played out, which I'll mention below. One thing to keep in mind, however, is that draws by agreement are often used by players in long tournaments as a way of preventing fatigue or simply playing on in dead positions until someone makes a mistake, and it's up for debate whether forcing/encouraging play in such conditions makes for chess that is more interesting or of better quality, or if it detracts from the events in which those rules are used.

The most commonly talked about variant is what are known as 'Sofia rules' (introduced in a tournament at Sofia in 2005), which states that no draws can be agreed before the position itself becomes a theoretical draw, though this assumes that the arbiter is theoretically competent enough to realise that the drawn position is a draw, and doesn't stop the players deliberately trading down into such a position.

The main other option that has been suggested is to provide more points for a win than for a draw, thereby hopefully making the players want to push for a win as a win and a loss is still worth more points than two wins. There has been some discussion that this is unfair to players in hard-fought draws, however.

I'll also link you to this wikipedia article, which lists some other things that have been suggested over the years.

# Answer
> 0 votes
Yep. Mark Dvoretsky's proposal (that eventually became "Sofia rules") and doing things like borrowing other sports use of 3 points for a win and 1 point for a draw (the essential property being needing more than 2 draws to equal one win) have all been tried (including one rather complex system involving giving different points for draws with white and black). Other proposals that have not been tried involve making changes to the rules of chess itself, such as making stalemate into either a loss (for the side being stalemated) or making it count as something less than a draw.

Ironically, one that saw a great deal of success was tried and later discarded in the 19th century. The essence of the rule was that in the event of a draw, the players would reset the pieces and play another game, because a decisive result was required before their encounter could end. As defensive technique improves, this becomes onerous if the same time control is employed, hence today's match tie-breakers of constantly descending time controls. I've often wondered what would happen if a one-round-per-day tournament today used that technique: In the event of a draw, reset the pieces and play g/30, then g/15. then g/10, etc., until a decisive result is achieved.

---
Tags: rules, draw, tournament
---


# Question
Title: does anyone use OSX Xboard app in Mavericks?
There's been talk about this app's release but I don't seem to be able to track it down and download it. I'd love to have Xboard native app for my Mac. Can anyone help? Any help appreciated greatly.

# Answer
> 1 votes
Winboard is what can run in wine. Though macwine is limited to 32bit executables. Xboard on the other hand always could be compiled in OSX just fine! I created an .app package ready for use and I'm told works fine in 10.10-10.6

It is a GTK2 app running through Quartz, so no X11 server app is needed.

http://www.open-aurec.com:8080/wbforum/viewtopic.php?f=19&t=53274&p=200662#p200662

# Answer
> 0 votes
Ummm. https://www.gnu.org/software/xboard/whats\_new/4.8.0/index.html

> With XBoard 4.8.0 the GTK build can be considered as stable as the Xaw build. In some areas it might not be perfect yet in all areas, but in other areas, such as the ICS Interaction window, it is already developed beyond the Xaw version, and the GTK build is in general superior to the obsolete Xaw interface.
>
> The GTK build can also be interfaced with OS X through the GtkOsx library. So OS X is now amongst the officially supported platforms, and a special configure option is available to build XBoard as OS X App.

That having been said, I haven't used it. It would appear from the notes that's not only able to be built as an OS X app, but an app bundle can be found here: http://www.open-aurec.com/wbforum/viewtopic.php?f=19&t=53274

Hope that helps.

---
Tags: software
---


title: Can Black create the second weakness?

text:
# Question
Title: Can Black create the second weakness?
I have played blitz game on *lichess* as Black and entered into drawn bishop endgame. My opponent tried to force the matters and lost in the end but at some point very interesting position arose, where White had only one permanent weakness.

I am interested to know if Black can win the following endgame by creating second weakness in White position, or simply breaking through with his king.

```
[Title "Black to move"]
[fen "8/p7/2bk1p2/2p3p1/5PP1/1B4K1/PP6/8 b - - 0 1"]

```

# Answer
> 2 votes
After **1...Bd5**, Black can win at least a pawn. White cannot take on **d5** because that's a clearly won king endgame for Black- Black threatens to go **Kd4-Kd3-c2** and take the pawn on **b2**. If White tries to defend with **Ke2**, then **Ke4** from Black wins the **g-pawn** and the game.

---
Tags: analysis, endgame, bishop-endgame
---


# Question
Title: A conditional retrograde analysis problem
Here is the problem-find a chess game that begins with 1. e4 and ends on the fifth move with knight takes rook mate, which determines who gives the mate.

This is a famous puzzle. For additional information and its history, see this nice article on ChessBase.

# Answer
> 11 votes
The solution is as follows:

> 1.e4 Nf6 2.f3 Nxe4 3.Qe2 Ng3 4.Qxe7+ Qxe7+ 5.Kf2 Nxh1#

---
Tags: problems, retrograde-analysis
---


title: First play in middle game

text:
# Question
Title: First play in middle game
I have a problem when I have developed all minor pieces and castled. The position looks perfect for me and my opponent. I don't want to move a piece since that would ruin the position and create weaknesses. Most often I end up with an unclear attack that works or not, i.e. I jump out and see what happens. Is this an unknown problem? Am I just lazy in calculating? Is there some good source to help me (drugs, books website, rules of thumb)? What should I look for? Should I think in some special order? Does this stage have a special name?

# Answer
> 1 votes
You're having issues with the transition to the middle game. I'm not sure what your current skill level is, so this advice is going to be a bit scattered.

First World Correspondence Champion CJS Purdy (Art of Chess Annotation vol 1 and/or Search For Chess Perfection) details a thinking process which consists of things to think about when on move and when your opponent is on move. Jeremy Silman (How To Reassess Your Chess) has a modified version of it. There's another approach in Alexander Kotov's Think Like A Grandmaster.

If your problem is more what to think than how, Former World Champion Max Euwe (with Walter Meiden) did a two-volume set (Middlegame) and the Soviet school was fond of a two-volume set from Romanovsky of the same name.

They all say it better than I can, but the tl;dr of it is that once you have completed development you look first for the tactical opportunities your opponent will give you. Everyone you play will give you those opportunities, you just need to be able to recognize them when they happen.

Sometimes there will be nothing specific to do. If that's the case, then proceed with a more general approach.

Try to "read" the position, the way a golfer might read a green; look for strengths and weaknesses in your opponent's position and your own. Your task is to weaken your opponent's strong squares, and use their weak squares to advance your pieces across the the center of the board. As for your own, you eliminate your own weak squares and keep the strong ones strong.

As you might expect, you can't do all four at the same time, so your thinking centers around what weaknesses you can exploit that will gain you more than you lose by exploiting them, and whether your own weaknesses can be easily exploited. (A weakness isn't real unless it can be exploited.) As you locate tasks (undermine this point, occupy this one with a knight, defend this) you'll see that some fit together into a sequence (can't occupy this outpost until I control this other square, need to defend this point so the opponent can't get around me, etc.) and that "sequence" is called a plan and you decide to follow it until/unless something better presents itself.

Kind of vague, I know, but so was the question.

---
Tags: middlegame
---


# Question
Title: Endgame player vs middlegame player: Is the result inevitable?
I recently asked this question: Why Anand and Carlsen insisted on playing the same opening/defense

**FM Rauan Sagit** answered:

> In my view, in terms of opening preparation, the Anand team failed to obtain middle game positions that suited Anand's style. In general, I think that Anand should have aimed for long middlegames with most pieces intact. While Carlsen should have aimed for long endgames with most pieces exchanged off the board. From this point of view, Carlsen got his types of positions, while Anand failed to get his. This can partially be explained by the chosen opening systems. Additionally, I think that Anand should not have willingly exchanged queens in a single game.

That got me thinking, when a strong endgame player faces a strong middlegame player, does the latter stand a chance?

The endgame player would force the opponent into exchanging pieces and there's nothing you can do about it simply because he doesn't care about his pieces, just like what happened in the championship match, am I right? What are the odds of a middlegame player defeating an endgame player?

# Answer
> 7 votes
My point was that Anand could prevail in dynamic middlegame positions, while Carlsen could prevail in endgames with a minimal advantage. Of course, Carlsen masters all three phases of the game on a top level. At the same time, sharp and complex middlegame positions release more adrenaline and require more focus. Regarding comparing a middlegame expert and an endgame expert, it is not so easy to exchange pieces. An exchange of pieces is a mutual decision and it takes two to tango. One way of keeping most of the pieces on the board is to select opening systems accordingly. For instance, you can choose the Volga gambit

```
[FEN ""]
1.d4 Nf6 2.c4 c5 3.d5 b5

```

and most of the pieces will be on the board for a good while. In some systems, it is easier for the endgame expert to steer the game towards e.g. an early exchange of queens. While in other systems, it is much more difficult to steer towards multiple exchanges. That being said, all the professionals are experts in all three phases of the game. So the key is to steer towards positions where they risk the most and therefore create the situation they prefer to avoid.

# Answer
> 4 votes
Anand's problem was mainly psychological. Anand is a world class endgame player, but he made some careless mistakes.

You can't really be considered a strong middlegame player if you have no endgame concept. Recognizing favorable endgames while calculating variations in the middlegame is part of being a strong middlegame player. But perhaps some players don't know how to proceed once they transition to that endgame? If that's the case, I would favor the stronger endgame player to win.

Obviously endgame skill is more valuable to have, it serves as the backbone for the opening and middlegame. Imagine a so-called "Strong" middlegame player who knows how to exchange into a favorable endgame, but has no confidence in his endgame skills?

# Answer
> 2 votes
"What are the odds of a middle game player defeating an endgame player?"

Well, given the Kasparov-Karpov match history, I'd say, "Pretty Good!"

Seriously, the answer is less about phases of the game and more about the players themselves. The "endgame player" has to be able to survive the best shots of the "middlegame player" before the endgame even arrives.

In the case of Anand-Carlsen, I really don't think second-guessing Anand's match preparation means anything. From where I sat, Carlsen would have won, no matter Anand's preparation. He's simply the better player, and while short matches like the current WC events allow greater probability for randomness to elevate the lesser player, it wasn't enough to save Anand.

Just like Fischer wasn't going to be beaten by any of his elders, and Karpov, and Kasparov, Carlsen is going to sit in that seat until one of his generation, or the next, rises up (Caruana, perhaps?) to unseat him.

# Answer
> 1 votes
I think it would be wrong to say that Carlsen as a middle game player is weaker than Anand. Carlsen is a quite strong middle game player, and the reason why he was eager to play end games was that he was getting minor advantage for his pieces in the middle games. He is the strongest player in the world, and having almost 100 points difference before the match was the indicator of the difference between Carlsen and Anand.

# Answer
> 1 votes
I would say that a strong middle game player would understand the middle game enough to know that the particular stage sets up the middle game. For example, simple things like pawn islands, doubled up pawns, bishops, pawn structure, and backward pawns are things that good middle game players will look for. Thus, even if the good endgame player gets the game to the endgame, the middle game player would already have an advantage. Seems to me that the middle game player has considerable better chances.

---
Tags: theory, endgame, middlegame
---


# Question
Title: Where can I see the recorded chess matches?
I want to know if there is any web site that maintains the recording of the famous chess tournaments. I am not looking for the video recordings, but the recording of the moves. For eg. I am currently looking for all the recent matches held between Carlsen and Anand in November, 2014.

# Answer
I would recommend chessgames.com.

For example, if you want to find out more about the Zurich 1959 tournament, just go to the mentioned site, find a link to Collections and search for Zurich 1959. You should be able to find this link, with the list of all games played there, sorted according to rounds.

To find all games between Carlsen and Anand in 2014, just use the search bar on the homepage of chessgames.com. To find the WCh match in 2014, follow the above procedure and it should lead you to this link.

Enjoy!
> 4 votes

# Answer
This Week In Chess is probably the best place to go for those. New game files are posted weekly. Though in the case of Carlsen-Anand 2014, it's probably available from dozens of places, including the official website of the match itself: http://www.sochi2014.fide.com/results/
> 4 votes

# Answer
database.chessbase.com/

I recommend you this, it is one of the oldest and best chess database, containing most of all the recognized rated games. Also, there are lot of features in here, for example: You can make your moves or place a position on the board you wish and search for the same kind of position played by any player and then also go through the whole game.

Also there is computer analysis to the downright of the screen to check what the computer evaluates after each move.

Hope this helps. :)
> 3 votes

---
Tags: learning
---


# Question
Title: Open Sicilian Variation, newbie question
Im pretty new and i was analyzing the opening stages of one of my recent games. I was playing white and we started off `1. e4 c5 2. Nf3 Nc6 3. d4 e6`

```
    [StartPly "6"]

    [FEN ""]
    1. e4 c5 2. Nf3 Nc6 3. d4 e6 4. Nc3 (4.d5 Nd4 5.Nxd4 cxd4 6.Qxd4 Qb6 7.Be3 Qxd4 8.Bxd4 exd5 9.exd5 Ne7 10.Nc3 Nf5 11.O-O-O Nxd4 12.Rxd4 Bc5 13.Re4+ Kd8)

```

Now my next move was `Nc3` (but doesn't really matter) and the lichess computer analysis marked this as a mistake and proposed playing d5 instead (leading to the computer generated variation `4.d5 Nd4 5.Nxd4 cxd4 6.Qxd4 Qb6 7.Be3 Qxd4 8.Bxd4 exd5 9.exd5 Ne7 10.Nc3 Nf5 11.O-O-O Nxd4 12.Rxd4 Bc5 13.Re4+ Kd8`) which presumably has me 1.4 pawns up. I looked up this variation on chesstempo and found that it was never played in 2200+ vs 2200+ play, but used 57 times in all games of the database. In those game it lead to white winning in 82.5% of the games.
Which variations make this move "bad" in top level play (except for the fact that `3. d4 e6` wouldnt happen in the first place aka preselection against this variation)?
What are good alternative 4.?
If the d5 variation is not that strong, why does the computer engine still recommend it. Is it just an error in the way it assesses the position, is there a lack of depth / computing time?

# Answer
I might be misinterpreting your question but it seems that you're asking something like this:

> My computer says that such-and-such a variation of the Sicilian defence is really strong for white but it never comes up in games between strong players. Has my computer made a mistake?

No, your computer hasn't made a mistake. The reason that this variation never comes up in games between strong players is that it's too good for White. Black has plenty of better options than allowing White to get into this position. Black's a whole pawn down, he has an isolated pawn and he still has a lot of work to do to get his pieces into the game; in contrast, after something like Bb5 and Rhe1, White has everything developed, has full control of the open e-file and is aiming a lot of material at the vulnerable e8 square.

Black's mistake is 3... e6, which looks like it controls d5 but doesn't because white can just play 4.d5 and either win a pawn or kick Black's knight around.

Ultimately, the point of 1... c5 is to prevent White from playing d4 because, if he does, Black will exchange his c-pawn for White's more valuable d-pawn. Typically, White says "I don't care!" and plays d4 anyway, since exchanging pawns on d4 gives White a strongly placed piece in the centre. Because Black doesn't have a c-pawn any more, he probably doesn't want to play ... e5 to push the piece from d4, because that would leave his own d-pawn backward and vulnerable.

By the way, after 3... e6, there's nothing particularly bad about 4.Nc3, *per se*. Indeed, after 4.Nc3 cxd4 5.Nxd4, we've reached a perfectly normal variation of the Sicilian via a different move order: the normal route to that position is 1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 e6 5.Nc3. Both sides have a decent position; the only problem with 4.Nc3 is that it fails to punish Black's mistake.
> 2 votes

# Answer
4.d5 move is strong. Black 3. e6? wasnt good. After 1. e4 c5 2. Nf3 Nc6 3. d4 your opponent should play cd4 and after 4. Nd4 e6

This variation of course doesnt exist in top level play because 3. e6 was horrid.
> -1 votes

---
Tags: opening, sicilian-defense, minor-variations
---


# Question
Title: Why does Stockfish give "score mate -7" for this position?
I'm running Stockfish with MultiPV=7:

```
script: setoption name MultiPV value 7
script: ucinewgame
script: position startpos moves d2d4 g8f6 c2c4 g7g6 b1c3 d7d5 c1f4 f8g7 f4e5 d5c4 e2e3 b8c6 d1a4 e8g8 e5f6 g7f6 f1c4 a7a6 c4d5 b7b5 a4d1 c8b7 a2a3 e7e6 d5f3 c6a5 f3b7 a5b7 b2b4 c7c5 b4c5
script: isready
engine: readyok
script: go movetime 600000.0

```

When I look at the "multipv 7" lines, I see a strange evaluation at the end of the analysis:

```
engine: info depth 1 seldepth 1 score cp -74 nodes 463 nps 66142 time 7 multipv 7 pv e6e5 g1e2 e5d4 e3d4
engine: info depth 2 seldepth 2 score cp -74 nodes 1314 nps 187714 time 7 multipv 7 pv e6e5 g1e2 e5d4 e3d4
engine: info depth 3 seldepth 4 score cp -79 nodes 3193 nps 399125 time 8 multipv 7 pv d8c7 c3e4 c7a5 d1d2
engine: info depth 4 seldepth 6 score cp -106 nodes 6224 nps 622400 time 10 multipv 7 pv d8c7 g1e2 c7a5 d1d2
[268 lines omitted]
engine: info depth 31 seldepth 52 score cp -70 nodes 3472890690 nps 6622358 time 524419 multipv 7 pv e6e5 c5c6 a8c8 d4d5 d8a5 g1e2 e5e4 a1c1 b7c5 e1g1 f6e5 d5d6 f8d8 c3e4 c5e4 d6d7 c8c7 d1d5 e4c3 e2c3 e5c3 d5d6 c3b2
engine: info depth 31 seldepth 52 score mate 0 upperbound nodes 3666345467 nps 6585523 time 556728 multipv 7 pv d8e7 a1c1 a8c8 c3e4 e6e5 d4d5 b7c5 d5d6 c5d3 d1d3 c8c1 e1d2
engine: info depth 32 seldepth 52 score mate -7 lowerbound nodes 3696286819 nps 6601691 time 559900 multipv 7 pv d8e7 a1c1 a8c8 c3e4 e6e5 d4d5 b7c5 d5d6 c5d3 d1d3 c8c1 e1d2 e7e6
engine: info depth 32 seldepth 52 score mate -7 nodes 3992249349 nps 6653549 time 600018 multipv 7 pv d8e7 a1c1 a8c8 c3e4 e6e5 d4d5 b7c5 d5d6 c5d3 d1d3 c8c1 e1d2 e7e6
engine: info nodes 3992249349 time 600018
engine: bestmove d8a5 ponder g1e2

```

Why does the 3rd-to-last line give "score mate -7"? I believe this is a lower bound due to pruning (as in my previous question), but the line does not say "lowerbound". How can I extract the correct evaluation? I doubt the position is a mate in 7.

Full output is here.

```
[FEN ""]

1. d4 Nf6 2. c4 g6 3. Nc3 d5 4. Bf4 Bg7 5. Be5 dxc4 6. e3 Nc6 7. Qa4 O-O 8.
Bxf6 Bxf6 9. Bxc4 a6 10. Bd5 b5 11. Qd1 Bb7 12. a3 e6 13. Bf3 Na5 14. Bxb7
Nxb7 15. b4 c5 16. bxc5

```

# Answer
> 4 votes
Fist things first, I put the position into another chess program (Chessmaster, because I find it has the most reliable mate-search function) and told it to brute-force search for a mate. This is what it found:

So to answer one part of your question, no, there isn't a mate in 7 here.

That leaves the question of why you are getting the lines:

```
engine: info depth 32 seldepth 52 score mate -7 lowerbound nodes 3696286819 nps 6601691 time 559900 multipv 7 pv d8e7 a1c1 a8c8 c3e4 e6e5 d4d5 b7c5 d5d6 c5d3 d1d3 c8c1 e1d2 e7e6
engine: info depth 32 seldepth 52 score mate -7 nodes 3992249349 nps 6653549 time 600018 multipv 7 pv d8e7 a1c1 a8c8 c3e4 e6e5 d4d5 b7c5 d5d6 c5d3 d1d3 c8c1 e1d2 e7e6

```

I would suggest that the first of these is stating that as far as the engine has calculated, there is *no* mate in 7, hence the term lowerbound. The next line indicates that the engine is initiating a PV-search *for* a mate in 7.

# Answer
> -1 votes
Your largest issue here is the fact that you are using mutli-PV at 7. They often yield unreliable results, so I would recommend moving that down to 3 or lower. When I am doing serious analysis, I often keep it on 1 to maximize performance. After all, it takes more than n times longer per depth per PV.

Otherwise, the engine has no issue evaluating the position and does not find a false mate.

---
Tags: analysis, engines, stockfish, uci
---


# Question
Title: Caro-Kann advanced variation pawn sacrifice
I used to play the Caro-Kann a lot as black. One line that I reached many times in advanced variation is:

```
   [FEN ""]
1. e4 c6 2. d4 d5 3. e5 Bf5 4. g4

```

In this position I saw one game where Anand played Bc8 and in my experience this line is very solid. The move Bg6 suffers some pressure from the pawn sacrifice e6, when the development of the bishop on f8 becomes difficult, and white easily controls e5. I saw one game Topalov vs Morozevich where Morozevich played Bg6, but then Topalov did not commit himself with e6.

My question is: should the pawn sacrifice e6 be feared?

# Answer
> 6 votes
The move **4. g4** is slightly dubious compared to the more solid option of **4. Nc3** (among Nc3), as it forces white to play **5. f3** if black opts for the mainline **4... Be4**. Therefore I recommend this choice in general. It does, to an extent, weaken the idea of **e6**. However, **4... Bg6** is an option and a more common one at that.

The pawn sacrifice is actually quite common at the amateur level and can be an issue for the unprepared. Your most principled choice in your line is **5... fxe6** and it does work quite often well. After the mainline (if it can be so called) **6. Bd3**, black should continue **6... Bxd3 7. Qxd3 Qd6** followed by the eventual fianchettoing of the bishop.

While this will not give you a simple win as black, it is clear that black's position is at least equal.

---
Tags: opening, caro-kann
---


title: Best current player in the endgame?

text:
# Question
Title: Best current player in the endgame?
In one interview, I do not remember when (please if someone knows give the link), Kramnik quoted that the best endgame player is Alexei Shirov... I think this interview was around year 2000. Obviously for anyone to reach the very top level they must be very strong in the endgame. Now, I do not think anyone would support Shirov as the best in endgame because he is not top 20 anymore and the world champion extracts most of his wins in the endgame.

Who is the strongest player in endgame nowadays?

# Answer
The blatantly obvious answer would be Magnus Carlsen who is also the No.1 player in the world, his ability to squeeze out wins from drawn endings is unsurpassed (with a few exceptions, e.g Andersson and Smyslov). Other than that I would naturally consider Vladimir Kramnik, although it is very hard to draw the lines between the various stages of the game nowadays as most of the top players nowadays are extremely versatile and have a universal style of play.
> 3 votes

---
Tags: endgame, super-grandmaster
---


# Question
Title: Chess As It Relates To Elaborate Endgame Strategies
Not sure if this is relevant to chess, so please redirect if necessary. But I figured I would get the best chess-based response here.

How would one apply the principles of chess to everyday life? There is always a lot of talk in fiction about how some character is a great chess prodigy which helps him make lots of money somehow or achieve impossible feats because they can think 20 steps ahead. This causes me several problems:

1. Often you are thinking of what you want to accomplish, while your opponent is thinking about what he wishes to accomplish. While we can anticipate their reactions to our moves, how is it possible to anticipate all of the variables when considering the opponents desires AND their reactions to our moves.
2. As a result of Problem 1 above, the equation is constantly changing, not only rearranging but also completely reformulating... all in your head. It is one thing to master maneuvers in the game of chess relative to its rules and layout, but I am talking about translating these skills to any game, or situation in life, and on the fly. Experience in a single task is one thing, but this adaptability I am referring to is another.
3. As a result of Problem 1 and 2 above, often times our end moves depend on some key decision or action by our opponent, usually at a crucial point that determines if we will continue with our current strategy or not. Better plans would not rely on this, but this seems to be inevitable. Sure, one can bottleneck their opponent into a situation where they are forced to make the move you desire them to make, or make them think that their move is what they want to do, but this reliance has often proven to be problematic. Not only because it is difficult to anticipate all possible moves, but also because of mere chance and environmental variables (completely uncontrollable and seemingly unforeseeable).
4. As a result of Problem 1, 2 and 3 above, it seems unlikely or almost silly to pick out a game plan to begin with, in chess or in life, and move solely towards that goal. Yes, it is possible to set out on a journey for a particular destination and adjust accordingly to reach that destination when steered off course. It is also sometimes desirable to sometimes "land" somewhere near your desired destination because near enough is good. But when people execute plans that are 20 steps in advance and calculate all possible configurations leaving nothing to chance, this seems to me to be impossible or not a reality for most people to able to perform.

To sum: In fiction and (I think) real life, elaborate plots which involve many variables often tip their hat to a foundation in chess. I understand fiction is fiction, and many of these plots are unrealistic, but is it possible to think this way without being a savant?

CLARIFICATION:
I changed the title to reflect that the question is mainly dealing with elaborate endgame strategies. These occurs both in life and also, I believe, in chess. Clearly, I am not an avid chess player, although I have a working knowledge of the game. Perhaps my understanding of how different chess strategies work and how agile they can be, but you often hear about people playing the game in their head before it is actually played which would seem to be a useful skill if applied to a majority of such sequentially reactive tasks. From the answers I have received thus far, it seems that there is very little correlation in between good at chess an then being good at something else with little practice of a result of having their chess skills. When I say "something else", I am mainly referring to life and dealing with its problems, which could be reduced down to a sequentially reactive series or tasks. From what it sounds like, the reverse may be as equally true: someone good at business, sports, military or other strategic game might have a propensity for chess when first beginning.

This is not a philosophy forum, I understand. But if I asked this question in the Philosophy section, how many knowledgeable chess players would be answering?

To finalize my point: mastery of the strategy game "Go", or "Wei Qi"/"Weiqi" in Chinese, is one of the four cultivated arts, and was probably considered this due to the strategy-based techniques it requires and mental abilities it may (or may not) develop. This has not been proven, if you believe what you read in the 'Psychology' section of the "Go" Wikipedia article. This game shares many fundamental qualities with chess, in my opinion, so I was curious if chess also cultivates something more in a human being than, say, playing a musical instrument or a sport.

And then to bring it full circle and lose even more readers:
This question may have been two seperate parts that I was trying to combine into one.
1. Does elaborate endgame strategy truly work despite my claims for Problems #1, #2, #3 and #4 in the original section of this post?
2. Can the elaborate endgame strategy learned and used in chess be applied to life directly?

# Answer
Garry Kasparov wrote a book called *How Life Imitates Chess*, where he considers parallels between the two.

I will point out that this is a controversial topic though. For example, its been observed that strong chess players have strong memories, but does that apply off the chessboard?

Anyway, chess *may* help you develop transferable skills, such as logic, predicting competitors' actions, building a strong memory etc., but the jury seems to be out on this one. But not many people would argue that playing chess gives you exceptional abilities as described in popular fiction.
> 3 votes

# Answer
Based on my personal opinion: I'm not sure I understand your question entirely, but if your question is: "does chess help you solve everyday life problems", I would say not more so than any other sport/hobby/(insert some thing that requires skill to master).

I saw an excerp from a documentary about chess players being made around the time of the Olympiad in Tromso, where the narrator makes a statement similar to: "I'm going to ask the best minds in the world how they would go about fixing the world". Part of the documentary featured Kramnik in explaining how he is shocked at how business people fail to "consider the moves of their opponents, which comes naturally for me as a chess player". I stopped watching at that point, because I think the documentary failed in its premise.

Chess GM's or players do not have superior minds, better thinking ability, higher IQ's or any other special intrinsic skill that "ordinary" people do not have, except for one - they are better at playing chess. People get good at something if they devote time to it, find it interesting, keep at it and yes, have some talent and psychological traits for it. Being good at chess does not mean you are going to be good at anything else (i.e. business, politics, maths, whatever).

Yes, that means I don't think Kramnik's view on how to go about doing business means much. I'm not saying he is necessarily *ignorant* or *uninformed*, but the fact that he is a super GM at chess gives him no credentials to comment about doing business any more than if we were to ask Bono, Stephen Hawkins or Messi.
> 1 votes

---
Tags: learning, theory, strategy
---


title: Does ...b5 give Black an advantage?

text:
# Question
Title: Does ...b5 give Black an advantage?
After being squeezed for an entire game I got the chance to ease my position with a pawn exchange. Incidentally, this would open lines for my pieces to attack opponent's weakened king. I played `...b6-b5` in the position below, and won. Computer played badly so I ask here for help to determine objective assessment of the below position -\> does `...b6-b5` give equality for Black or can he aim for more?

```
[Title "Black to move"]
[fen "2r3k1/p4p1p/qp2p1p1/4Q3/2PR1P2/P7/1P4PP/7K b - - 0 1"]

1...b5

```

## EDIT:

To help the viewers understand the nature of this question, here are the lines I saw that convinced me that Black suddenly gets good chances after `...b5` :

```
[Title "Black to move"]
[fen "2r3k1/p4p1p/qp2p1p1/4Q3/2PR1P2/P7/1P4PP/7K b - - 0 1"]

1...b5 2.c5 (2.Rd7 (2.cxb5? Rc1+) 2...bxc4 3.Qf6 Rf8 4.Qe7 {Trying to win back the pawn} c3! {With the threat of Qf1 checkmate, and cxb2 Black should win in my opinion} ) 2...b4! {Threatening Qf1 checkmate} 3.Qe3 $8 bxa3 4.bxa3 $8 (4.Qxa3? Qf1$) 4...Qf1 5.Qg1 Qxg1+ 6.Kxg1 Rxc5

```

I think `2.Rd6` was played in the game but I can't remember what happened nor what I had in mind as a response... Since it is clear that after that move Black must defend, my question is answered -\> Black can not aim for more than an equality :(

# Answer
> 3 votes
2. Rd6 followed up with 3. c5 looks strong for White, unless I am missing some obvious tactics.

---
Tags: analysis
---


# Question
Title: Is studying computer games legal in correspondence chess?
I have recently umm downloaded the Dragon Cookbook from Chessbase. It is filled with human and computer games in the dragon. The thing is, are previously played computer games allowed to be seen in correspondence chess?

# Answer
On chess.com, use of books and game databases is allowed. Use of engines and tablebases is not. Your book is either a book or a game database and therefore fine.

There are also sites that don't allow any outside help (no books, no databases), and on the other hand the ICCF (the offiical FIDE-affiliated Correspondence Federation that is also completely online nowadays) does allow engine use, so it's best to always check the rules of the actual site you're using.
> 5 votes

# Answer
It is not illegal to view and use previously played Chess games, some people even use Chess Analyse programs while playing on (for example) the internet. However most websites do not allow you to use programs to gain benefits over other players, including but not limited to analyzers.

Ofcourse it is allowed to study previously played Chess games, you can even learn a lot from them!
> 2 votes

---
Tags: opening, engines, correspondence-chess
---


# Question
Title: Is there any way to extract PGNs from a DGT live games presentation?
For example:

http://www.budva2013.org/live/d/tfd.htm

I have no particular interest in this tournament, but I often seen displays like this and wish to extract games without needing to type them out manually. Is there some way to download the PGNs?

# Answer
> http://www.budva2013.org/live/d/tfd.htm

If you remove the last file name, you get the listing of the contents of the directory:

> http://www.budva2013.org/live/d/

The .txt files are files used by the Flash program to find the moves. But there also is a pgn file:

> http://www.budva2013.org/live/d/games.pgn

However, if I recall correctly, the pgn file does not always exist. If it does not exist, one way would be to write a script that parses the pos##.txt files which contain all moves even when the games are ongoing. I thought of doing that before the pgn files started appearing (probably an update of the dgt software?) in the directories, but never got started.
> 2 votes

---
Tags: pgn
---


title: Chess Statistics How to?

text:
# Question
Title: Chess Statistics How to?
I am a graduate student studying statistics and I play chess once in a while for fun.

I was thinking (just for the fun of it) -- applying some of what I've learned in statistics to chess games: I want to perform statistical analysis of chess games.

Note: My primary purpose is recreation:

1. Tinkering around
2. Re-producing earlier works -- for example how much of an advantage does white have over black
3. Looking at mid-game winning patterns
4. Etc. etc.

So to that:

1. I need a large collection of chess games (historic data)
2. I will then analyze them using R which is a statistical programming language

Question:

1. I'm looking a collection of games that I can then use as my data set (I would love to get a list of open source chess databases -- commercial chess database might have restrictions on em)
2. I'm looking for any reference material -- like seminal papers in this area.

Thanks.

# Answer
> 2 votes
I started doing something similar some time ago. So I can give you some advice. As already stated by @Student T, you need to define precisely which is the question you want to answer with statistics. I will not repeat his argument which is complete enough, but let me just say that defining well your problem is essential to select your methods of analysis and the selection of data.

1. The dataset. If you are interested in analysing games, one good option might be the The Week In Chess database, which includes all the games of international competitions (= games of high-rated players). Another possibility is the million base, containing 2.2 million games. Whereas if you are interested in analysing ratings, you can download FIDE rating list here, for example. In downloading the dataset(s) you want to use, you should consider the following:

1.1. The format: chessbase format is proprietary, which means it is difficult to know which are its specifications and, in consequence, to extract the data. The format pgn is more convenient, you can process it as a textfile and extract the information you need using the pgn file specifications.

1.2. How to filter the data / which data to include in the database (in statistical parlance, sampling and stratification issues). For this you need to specify which is your population. Are you interested in games of high-rated players? Then, it is easy to find the games and databases include many. In contrast, it is more difficult to find games of unrated or lower-rated players, but you can find some of them in the websites of some national chess federations (Canada, Scotland, Wales, Ireland...). Also, there might be differences in the behaviour of chess players depending on the type of competition (individual or by teams; human, computer or correspondence games; etc.). Do you include all type of competitions or you leave out some of them?

1.3. Rating systems inhomogeneities. Chess rating systems are usually based on professor Arpad Elo rating system, but with different coefficient values. For example, USCF and FIDE ratings are not equivalent. And the value of coefficients can also change with time (see here for an example).
2. Some bibliography. I can hint you little reference material. Some time ago I did a quick search on Scopus and didn't find any interesting article (but you could try to dig deeper). However, some years ago I looked through a book on chess and mathematics. It dealt with geometrical, combinatorial and probability issues, but not with statistical analyses. It was originally written in German and there is also a translation to Spanish, but I don't think there is an English version. You can find some similar references in Wolfram MathWorld's Chess article. You might also be interested in this analysis of piece moving rate as a function of Elo rating. Regarding the rating system, the seminal work is professor Elo's book *The rating of chessplayers, past and present*.

# Answer
> 5 votes
I'll leave others to point you a correct database for the games because I'll focus more on the statistical part.

First, you need to ask yourself what you want to analyze. If you don't know, you should really ask yourself what problem you want to address. Your question simply say "I want to do something, but I don't know what to do.". There're infinite ways how a database of chess games can be analyzed. I'll point to you for some areas.

1. Whether white has an advantage

Given a large data set, if we assume the games are independent we might strip away the draws. Then we might assume a binomial distribution with p=0.5 and try to detect statistical significance. However, this approach assumes that the players are equal.

2. There's rumor that Carlsen got most of his points from players older than him (last generation like Anand) but suffers against like Caruana and Giri. Is that true?

You might use a two samples-mean t-test or something like that.

3. Whether Elo rating is really inflated
4. Given a set of games between two players (or computers), is one player really better than another?

For example, Carlsen has beaten Nakamura many games without a loss. Does it mean Carlsen is a better player? Did that happen because Carlsen was simply lucky.

5. Correlation between world-number one and world champion

Is there a positive correlation? Are they independent?

6. Whether the Elo rating system really make sense

There were some articles on Chessbase about it a while ago. I don't remember the names so you'll need google yourself.

# Answer
> 2 votes
That's an unique thing that you are doing. However to help you, to collect most of all the games played by recognized rated players around the world, the below website will help you.

database.chessbase.com/

---
Tags: statistics, chess-algorithms
---


# Question
Title: Why is it rare to see unusual "special" opening preparation by trailing player late in a match?
Taking the recent Anand-Carlsen match as an example, I know that grandmasters spend incredible amounts of time in opening preparation, and Anand's play to refute certain lines of the Berlin defense was impressive.

But once reaching game 10, 11, or 12 and desperately needing a win, why don't players make an effort to force the game off into some opening line that the opponent almost certainly hasn't prepared for? *Not* into some fringe or unorthodox opening, but into solid openings that are just much less familiar for the opponent.

Much the same way that an American football team must spend at least some small amount of time practicing "trick" plays, like on-side kicks or throw-back passes, or much like a football (soccer) team might practice very special free kick formation for late in a game when a goal is needed very quickly -- shouldn't it be normal to prepare for a championship match by spending at least a small amount of time studying some very different openings that the opponent has not faced recently or does not appear to be as strong in?

I'm not endorsing these as candidates for specifically Anand v. Carlsen, but I might have expected to see some different variations of Sicilian, or to see Dutch Defense, Benoni Defense, or to see Reti opening, and to play in lines that don't transpose easily to positions that are similar to the main lines played (Grünfeld, Berlin, etc.).

I'm not saying Anand's openings were the problem in the match -- he often played well with great opening prep and blundered later on.

I am just asking why it is so uncommon to see players deviate to some "special preparation" in late stages of a match when they are trailing and need a win.

Wouldn't that be one of the scenarios that they prepare for specifically prior to the match starting? "What if I find myself down 1 point late in the match and my opponent has shown clear strength in the most frequent openings from the match? How will I steer the game into unknown territory?"

# Answer
It happens, but there's a reason why it doesn't happen often, and, when it does, why it doesn't work.

First off, there's a psychological reason not to do it; it's uncomfortable. If the match is going badly for you, it's natural for you to fall back on familiar weapons: positions that you know how to play better than any others. When you do that, when you stand on familiar ("home," if you will) ground, you feel more secure and play better than if you're in less familiar territory. And when you play better, you're more likely to score better.

Also, there's the unknown. When you're down by a point late in the match, a single failure ends your chances. And, when you decide to divulge radically from your "normal" game approaches for this one game, you don't know with certainty how well your opponent can play those positions. So you divert time away from preparing to play comfortable positions even better than you currently play them (after all, no one plays their comfortable positions perfectly, there's always room for improvement) to learning how to play a completely different position passably well. And, when the day of the game dawns and you uncork it, you find out your opponent actually likes to play those positions, just never gets the chance to because opponents haven't so far let that happen. And down go your chances of leveling the match in a flaming crash.

Romantic notions like risking everything on one wild roll of the dice don't occur naturally to the vast majority of top chess players, because the tendency to do so keeps them from making it to the top, except in the rarest of circumstances.

A GM once told me chess was a little like tennis; "sometimes the only thing you can do is hit the ball back over the net and try to give your opponent another chance to make a mistake."

You're far more likely to see a player pull divergences like that that early in a match than late, such as Fischer pulling out 1.c4 to open Game 6 of the 1972 match (that match was for 24 games, so G6 there would have been like G3 of Carlsen-Anand). If it doesn't work, then the player still has the energy to save the draw if possible, and time to recover from the failure if not.
> 3 votes

# Answer
I looked through the WC matches since 1995 (Kasparov-Anand) to try to validate the claim that surprise openings aren't used very often at the end of matches. I found that generally this holds true, with some notable exceptions. Particularly, in both of his WC matches where he trailed with two games to go, Vladimir Kramnik has pulled out sharp tactical openings that he rarely or never played previously.

In 2004 vs. Peter Leko (http://www.chessgames.com/perl/chesscollection?cid=1002400) he was down 6.5-5.5 in a 14-game match when he played a Benoni in game 13. While he did not win that game, he generated excellent chances and likely missed a win in the endgame.

In 2008 vs. Viswanathan Anand (http://www.chessgames.com/perl/chess.pl?tid=65865), he was down 6-4 in a 12-game match when he played a Najdorf Sicilian in game 11. He did not win that game either, but he certainly avoided his renowned Berlin or the Petroff.

In 2013, Anand was down 5-3 going into game 9 of a 12-game match against Magnus Carlsen (http://www.chessgames.com/perl/chess.pl?tid=81142) when he played the 4. f3 Nimzo. He got a strong attack but ultimately blundered and lost the game.

However, there is an additional reason that surprise openings do not appear often, which is that many matches are level towards the end and both players want to get to the tiebreaks without expending too much effort. I find this to be the case in Kramnik-Topalov 2006, Anand-Gelfand 2012, and Anand-Topalov 2010 (although Topalov badly blundered in the last game and lost).

That leaves the following matches where a surprise opening did not appear: Kasparov-Anand 1995 (the last few games were sharp Sicilians, which had been played several times in the match already), Kasparov-Kramnik 2000, and Carlsen-Anand 2014. In Carlsen-Anand 2014, Anand had been getting good play from his openings as White and I see no reason that he should have deviated.

That leaves the only really inexplicable case as Kasparov-Kramnik, where Kasparov seems to have just lost his will to dominate after the match started out badly. He had been the dominant player in the world for over a decade and maybe finally being brought low was too fatiguing for him.
> 1 votes

---
Tags: opening, grandmaster, preparation
---


# Question
Title: Can Black perform a successful freeing break? If yes, what would be his long-term plan after?
I have tried to resurrect an old line and use it in my repertoire. Every single time I play it I reach positions similar to this:

```
[Title "White to move"]
[fen "r2q1rk1/pbpnbppp/1p2pn2/8/3PNB2/3B1N2/PPP1QPPP/R4RK1 w - - 0 1"]

```

Usually, engines and most human opponents continue with `c4`. I almost always go for `Re8` \+ `Qc8`, so I can safely play `...c5` (the Queen is off the d-file so there will be no pressure from a potential `Rd1`, and `Be7` is protected so there will be no `d5` tricks).

## QUESTIONS:

Can we confirm that this is the correct plan, or does Black have better moves at his disposal?

If my plan is viable, how should I proceed when White exchanges on `c5`-\> recapture with a pawn or with a piece?

What would be my long-term plan in the resulting position-\> minority attack with `...a6` \+ `...b5` or fighting for `...e5` push?

Thank you.

# Answer
> 2 votes
c5 is, by far, the preferred idea and line here, because it not only frees up the light squared bishop, breaks and challenges the d4 pawn, as in some Rubinstein lines, but also allows your queen to visit in e7, and park your rooks on c8 and d8 respectively.

It is by far, in terms of breaks, the most effective, and does not allow white the luxury of a kingside attack.

Therefore, as white, it would be beneficial, tactically, to park your a-rook on d1 to prevent c5 and then try to play on the d-file with doubled rooks and c3 (to prevent counterplay).

---
Tags: analysis, strategy, middlegame
---


# Question
Title: Make chess engine play a particular position
I want to be able to train my mating skills by making a chess engine play positions that others have resigned from. Is there a way to make a chess engine play a particular position? I am using stockfish and scid vs pc at the moment.

# Answer
> 3 votes
In Scid vs PC got to Edit \> Setup Board. Here you can setup the board with a particular position, set side to move and castling flags. Easier is if you have a FEN of the position, you could just paste this and use it directly. Click OK once you are done to get the position on the main board.

Now navigate to Play \> Computer-UciEngine \> Choose your stockfish engine, Check "Start from current position", Set desired time control and click "Play".

# Answer
> 1 votes
I have no specific knowledge about stockfish, but usually there is an Graphic User Interface (GUI) to a chess engine. The GUI allows you to edit a game (making moves---do this because it takes care of fine details like castling rights and right to en passant) or edit a position (placing pieces) and than let the engine play.

You can specify who is on the move and which colour(s) the engine should play independently.

---
Tags: engines, stockfish, scid
---


# Question
Title: Why do Super GMs still have to write down their moves at tournaments?
I thought that the boards can register the moves electronically. What is the point of writing them down?

# Answer
> 9 votes
I can think of several reasons:

1. The players will want to know how many moves have been played in the game (as you often get extra time after moves 40 and 60), how many moves have been played before the last pawn move or capture etc. Currently the players may not consult any other material than the score sheets during a game, but even if the rule was changed, the score sheet is probably the easiest way to access this information.
2. The electronic boards can be unreliable sometimes. Also, although this probably never happens in Super GM level, problems may occur with illegal moves etc.
3. There is no pressure to change the rules, or the trouble of changing the rules weighs more than the potential gain. Some players like the old-fashioned way of writing the moves down. Comparing with reason 2, somebody should decide when the electronic boards are good enough to be trusted, and drawing the line is not an easy job.

# Answer
> 4 votes
I'm not sure I understand the question properly. Are you suggesting electronic boards to print out the list of moves once the game is finished, so the players can sign it and save the time and effort to fill the scoresheets themselves during the game?

If you are proposing just to remove the scoresheet because there's an electronic register of the game, then I think the most important reason is that the scoresheets (because obviously there is one per player) are the only official documents, signed by both players, that attests that that game was played between those players and with the result that is noted on them (besides date, place, etc.). Eliminating this document would be like removing the signing of the wedding license because there's already a video of the ceremony.

# Answer
> 3 votes
The simple answer is because it is required by the FIDE competition rules.

The more complicated reason is that you cannot easily enforce other laws if you do not have your own written record.

For instance:

It is a requirement to record all draw offers by writing "=" against the move when a draw offer is made. It is illegal to disturb your opponent by making repeated draw offers. If this happens the only way you can prove this is by means of the written score sheets. Draw offers are not recorded electronically.

Draw by 3-fold repetition. If you make an incorrect claim for a draw by 3-fold repetition your first penalty is to have your opponent given an extra 2 minutes on the clock. For a second offence you lose the game. A 3-fold repetition can unfold over many moves. It is not required that it take place over consecutive moves. The only way you can double check this to avoid a penalty for an incorrect claim is by examining your own score sheet.

Note that in a recent GM competition where because of the time controls (either rapid or blitz) the players were not required to record the moves the British GM Nigel Short wanted to claim a draw by 3 fold repetition but didn't make a claim because he didn't have a written scoresheet. He went on to lose the game and raised the point afterwards.

Note that in any case rule 6.13 states that: "Screens, monitors, or demonstration boards showing the current position on the chessboard, the moves and the number of moves made/completed, and clocks which also show the number of moves, are allowed in the playing hall. **However, the player may not make a claim relying only on information shown in this manner**"

# Answer
> 0 votes
There's one reason I can think of which no one else mentioned. Super GMs might still need the scoresheet to backtrack to moves that happened earlier to get some clues on the opponents strategy or to think of lines in their theoretical preparation.

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Tags: notation, super-grandmaster
---


# Question
Title: How many moves ahead does Anand calculate in his mind?
I always wondered about this! How many moves ahead can strong players like Anand actually 'see' during the game? How does the calculation of a supercomputer like Deep Blue differ from that of strong human players?

# Answer
> 13 votes
first of all see here. here is a quote

> Asked how many moves ahead he can think, Kasparov replied that it depended on the positions of the pieces. "Normally, I would calculate three to five moves," he said. "You don't need more.... But I can go much deeper if it is required." For example, in a position involving forced moves, it's possible to look ahead as many as 12 or 14 moves, he noted.

for a supercomputer it obviously depends on how well-written it is, there is a concept called alpha-beta, which is used to limit thinking into unnecessary moves, like the computer usually wont consider the opponents (white) `c3`,`b5`,`d6`,`f7`, combo, on the first move. however after `c3`, `b5` it should consider `d6`, and have a reply ready. from a page called Creating a chess engine from scratch on chess.com:

> A computer can easily evaluate a few million positions per second, a human probably 1-2 positions per second!! Usually speed is measured in MNodes/sekund which means million positions (Nodes in computer science jargon) per second. Fritz running on my old laptop does about 2.5 MNodes while Deep Blue did about 200 MNodes per second. Raw power is not all - the evaluation function is also very important. Pretty much all engines use the same algorithm for searching through the search tree of possible moves to find the next move. This algorithm is known as alfa-beta search or it is some variant of this.

an important difference is that a computer has to consider things a human takes for granted, such as the concepts behind a known opening, even though a good program can remember which combos work (and rate them, then play based on its ratings), its extremely difficult for it to recognize concepts, such as a fork independent of the result, this can be a advantage because a human may fork, and not see another better future move.

hope that helps!

# Answer
> 9 votes
This is an ill defined question, similar to: what is my girlfriend thinking about when we ... ?

But to stab at an answer, it would be completely dependent on the position. If the position has many tactical variations possible, the answer will probably be *very* far, 5, 6 or more moves ahead.

If the position is very closed, and positional strategy matters, the answer is probably that he is largely relying on his previous experience, understanding of positional strategy, and analysis of openings/other tournament games in guiding his moves. This usually means he has memorized the possible variations and can move with confidence knowing he is not blundering.

If the position is considered an endgame position, once again, he should be able to see very far ahead since the number of tactics and variations is greatly reduced.

This is mostly true of all chess players, the difference being that master and grand master players can perform all of these things to a greater degree than lesser players.

In terms of how this applies to the development of a Chess Engine such as (Deep) Blue: it doesn't. Computers are largely computational beasts and other than large databases of known openings/endgame position and transposition tables they don't largely rely on previous experience. They simply search for the best move as defined to be the move such that the opponent's best (following) move is weakest (this is the principle behind the min-max search algorithm which is usually used in Chess Engines.) It is a well known trick that when a human is playing a strong computer opponent they should aim to create a largely positional game with few tactics in order to increase their chances of winning. Computers make far fewer mistakes than humans in calculating tactics and, in general, have poor positional play.

# Answer
> 5 votes
Just thought to add the famous story (likely apocryphal):

During a tournament in the 1920s a newspaper reporter asked Richard Reti how many moves ahead he could read. Reti replied *"I only see one move ahead: The right one."*

# Answer
> 5 votes
Players such as Anand and Carlsen can play top-level blindfold chess. I assume this means that the number of moves ahead such players can "see" is essentially unlimited: at the board they can presumably visualize a continuation of the game to its conclusion. But a single very deep search down a single branch of an enormous game tree, though very important in certain situations, is not in itself enough to produce the best moves (and also may not be the best form of time management).

# Answer
> 4 votes
How far ahead a strong player like Anand sees depends on the position. On move 1 he doesn't see any moves ahead because he doesn't know which of several perfectly good replies his opponent will play. In the endgame there might be a forced line which is 15 or 20 moves long which he will see and so, by the way, will many weaker players.

The two significant differences between a strong human and a supercomputer are:

1) A supercomputer can calculate much, much faster than any human and so can consider many more moves (orders of magnitude more) than any human in the same time.

2) Very strong players are much better at evaluating a position than supercomputers. This means that they can quickly reject unpromising lines and so dramatically reduce the number of variations they need to consider and do this much better than the supercomputer. Effectively they can often see as far, sometimes even further than the supercomputer.

Incidentally, this superior evaluation ability separates strong grandmasters from not only supercomputers but also ordinary players like you and me, or at least me ;-).

Weaker players are often not that much different in their calculating abilities from stronger players. They just don't recognize whether the resulting position is good or bad anything like as well as the stronger players do. Their poor evaluation abilities mean that they waste time, just like the supercomputer, analyzing unpromising variations.

---
Tags: engines, famous-players, anand, super-grandmaster, calculation
---


# Question
Title: In an ECF tournament, how are rapid play rules different from standard play?
I am interested in entering some rapid tournaments in England, and have heard that the rules for the rapid games are somewhat different than standard play rules. For example, I was told you can legally take your opponent's king if he fails to spot a check (and win the game in the process). Also, the touch-move rule does not apply - apparently you are allowed to touch a piece, take it back and play another piece - only when you press the clock does your decision become permanent.

I have picked up these hints from casual conversations at my local club - it is entirely possible that these are not really the "official" rapid play rules (ECF or otherwise) but that of a specific tournament, that these are actually blitz rules and not rapid play rules, or it may even be my club members taking my inexperience for a ride. Is my understanding of these rules correct? If I were to enter a rapid play tournament, what other differences from the normal tournament rules could I expect?

# Answer
> 4 votes
You should read the rules from this page, sections `A` and `B`. Also, I would strongly advise you to ask a referee about this **just to be safe** from making a mistake or from embarrassing yourself. You can come earlier before the game starts ( 1 hour will be enough for the referee to explain you everything you need to know and for you to have time to relax and psychologically prepare for the game ) and just ask him/her to explain you what you want to know ( it would be wise to write down your questions ).

> I was told you can legally take your opponent's king if he fails to spot a check (and win the game in the process).

I haven't had such a case, but if the opponent plays illegal move you **can stop the clock and claim a win**-see the rules in the section A in the link I posted.

> Also, the touch-move rule does not apply - apparently you are allowed to touch a piece, take it back and play another piece - only when you press the clock does your decision become permanent.

No, that is not the way I remember. If you touch the piece you **must play with it** but your opponent can hold it in the air / drag it over the board / continuously put it on the board-pick it up-put it on another square, **until he presses the clock.** This is very rude behavior but **is allowed.**

> If I were to enter a rapid play tournament, what other differences from the normal tournament rules could I expect?

Read the rules from the link I posted above, and talk to the referee before the tournament just so you can be sure and safe.

This is all I know, I haven't played blitz for 11 years-that is why I have advised you to talk a little with the referee.

If you have further questions leave a comment and I will try to help.

Good luck on your tournament!

## THIS EDIT CORRECTS MISTAKES POINTED OUT IN COMMENTS BELOW:

I will just quote member *Remco Gerlich* :

*About illegal move* ( **emphasis is mine** ):

> **In rapidplay**, an illegal move does **not lose** the game. The **same penalties as in slow play apply** (have to take it back and move with the touched piece, opponent gets 2 minutes extra on the clock, 3rd time in the same game is game loss). The difference with slow chess is that in rapid you must claim before you make your own move, in slow chess the position will always be reinstated no matter how long ago it happened. **Illegal move is only a loss in blitz chess (section B).**

*About making a move according to the rules*:

> Also, no you can't keep moving your piece until you press the clock, you can keep moving it until you let go of it.

Best regards.

# Answer
> 0 votes
I'm afraid the earlier answer is just plain wrong on the subject of illegal moves. An illegal move in both rapidplay and blitz does lose the game.

Here is the relevant section of the rules:

> An illegal move is completed once the player has pressed his clock. If the arbiter observes this he shall declare the game lost by the player, provided the opponent has not made his next move. If the arbiter does not intervene, the opponent is entitled to claim a win, provided the opponent has not made his next move. 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. If the opponent does not claim and the arbiter does not intervene, the illegal move shall stand and the game shall continue.

Note that if your opponent leaves his king en prise he has made an illegal move and if no arbiter is watching your game and so can't or doesn't intervene then you should claim the win. If you take your opponents king then you legitimize his move and are yourself making an illegal move. He can then claim the game!

Only in the special circumstances that a rapidplay competition had at least one arbiter per 6 players AND the arbiters recorded the moves would standard rules apply.

Regarding the question about touch-move in rapidplay, the first time I played a formal rapidplay competition I had the same belief as the OP. My opponent was bemused (but didn't actually burst out laughing) when at one stage I took back one move before pressing the clock and made another move. The arbiter soon put me right.

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Tags: rules, rapid
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# Question
Title: Question about solutions given in a chess book for mate-in-two and mate-in-three
I recently purchased the book "Chess: 5334 Problems, Combinations, and Games" by Laszlo Polgar, just to learn more about moves.

This book has 3411 "Mate in two" problems and 743 "Mate in three" problems. The book is great but I have a question about the solutions to these problems.

For example, the solution to this mate-in-two (white to move first) problem # 1135 (from p. 247)...

```
[FEN "rkn5/pp1R4/2pn4/2N5/8/8/8/K w - - 0 1"]

```

...is given (in figurine algebraic notation) as:

`Rb7`

The solutions to both the mate-in-two and the mate-in-three problems list only one step (the book does not explain the reason for this).

How should a person read this solution? Is it the supposed final location of the white rook? And is this way of listing solutions common practice in chess books?

# Answer
I think it's slightly unusual to only give the first move, or a little outdated. But it saves space and the assumption is that if you found the right solution, you can confirm it by seeing the first move.

I also think that Polgar originally intended this book (and his other "big books") as a collection of problems for *coaches* to select problems for their students from, because doing 5000+ mate in 2 and mate in 3 problems is a bit much for self-study. The coaches are expected to be of sufficient strength already, and to be able to select some problems with a common theme that they need for some lesson.

The whole answer, in this case, is of course 1.Rxb7+ Nxb7 (forced) 2.Na6#.

The 'x' and '+' in Rxb7+ are strictly speaking not necessary, so some books omit it. Again, that's a bit of an outdated practice since it's just not that user friendly.
> 4 votes

# Answer
The reason for giving just a first move is that the rest should be obvious (if you figured out the first move, you'd know how to continue). And yes, it is a standard practice.

> Is it the supposed final location of the white rook?

Again, yes. In a long notation the move would be spelled `Rd7-b7`, but since there's only one rook able to land on `b7`, the initial square is omitted. In short notation the initial square is only spelled out to disambiguate the move.
> 2 votes

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Tags: notation
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title: Has Topalov retired?

text:
# Question
Title: Has Topalov retired?
Topalov's rating hasn't changed since a long time. And he hasn't signed for any of the upcoming tournaments. I wonder if he has retired, after reaching that 2800 mark? He isn't playing the Grand Prix even.

# Answer
> 5 votes
I think there is no reason to suppose Veselin Topalov has retired.

> "Topalov's rating hasn't changed since a long time"

The last change in Topalov's rating was in October, just two months ago. He has previously spent periods of up to 4 months without playing. So that seems normal.

> "I wonder if he has retired, after reaching that 2800 mark?"

Topalov has been above 2800 before. His maximum rating was 2813 in 2006 and again in 2009. I don't see any reason why he should stop.

> "He isn't playing the Grand Prix even."

According to this interview (minute 8:30) given during the Chess Olympiad, he isn't a great fan of the Grand Prix series (see also here).

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Tags: famous-players
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# Question
Title: Illegal move or forfeit on time - who wins this 5-minute match?
In a 5-minute match a player makes an illegal move leaving his king in a check position. This usually gives the victory to the opponent, if he sees it and captures the king. Otherwise, if the opponent doesn't claim the illegal move within 2 moves, the game just continues as if nothing happened.

But what happens, if the opponent runs out of time just before he captures the king? Is it a time win, since the opponent didn't claim the illegal move within his time limit? Or does the illegal move automatically lose, once it is noticed?

If the illegal move automatically loses, that raises the following theoretical question: What if nobody immediately sees the illegal move, and the game is considered to be lost on time. But after a while the opponent notices the illegal move and claims it. Is there a time limit to that, and how is it enforced after the clocks have stopped ticking?

And lastly, would the decision be any different, if the match was longer/shorter?

# Answer
> 1 votes
I think the illegal move has to be noticed by the opponent who should then immediately stop the clock and call the arbiter to claim and get the victory. Yet if the opponent fails to notice the illegal move and runs out of time, then this player thereby loses on time.

# Answer
> 1 votes
An illegal move is completed once the opponent’s clock has been started. The opponent is entitled to claim a win before he has made his own move. However, if the opponent cannot checkmate the player’s king by any possible series of legal moves, then the claimant is entitled to claim a draw before he has made his own move. Once the opponent has made his own move, an illegal move cannot be corrected unless mutually agreed without intervention of an arbiter.

As far as the time/check priorities go... As far as I'm aware(and in any tournament I have played in thus far) any player that is first to claim for a win will win the game, UNLESS both flags have fallen in which case it becomes a draw. It is part of the game(especially in blitz) for a player to be aware of the clock and there is no default loss when a player's time hits 0 unlike online chess where this is done automatically.

EDIT:

Since someone wanted a conclusive pointer to a rule that enforces this... which took a while it is found in the fide rulebook which can be found at http://www.fide.com/component/handbook/?id=124&view=article There is also a short section regarding blitz(which is less than 15 minutes) which seems to handle the same format.

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Tags: illegal-move
---


title: How useful is Chess.com Chess Mentor?

text:
# Question
Title: How useful is Chess.com Chess Mentor?
So I've used the Chess Mentor feature on Chess.com, and completed all of the free courses, and am now using it at 1 lesson a day(extremely slow).

So, I've been considering buying a membership, namely a Diamond one. How useful is the Chess Mentor when considering non-private coaching? By that I mean a class with about 15-20 people taught by a 2000 rated player (Don't have many good players in my country). Would it give a noticeable increase in performance, or would it be just a slight improvement?

# Answer
> 2 votes
I personally don't benefit much from the mentor. However, that is just a preference in learning styles.

However, I still highly recommend a diamond membership for the tactics trainer and videos, as a good, organized at of videos with tactics will make your rating skyrocket!

I suggest Colle-Zuckertort/London systems and Dutch stonewall.

# Answer
> 2 votes
Me too! I am also a free member at chess.com (@datfreshmandude if you're daring to look for me;) ) and Chess Mentor has helped me to a small degree. It has helped me in openings, and the advantage to Chess Mentor over Tactics Trainer is that Chess Mentor not only gives reasoning for why a solution is right/wrong, but it is also written by GMs and IMs (at least I think they are). So you are almost sure to get a good lesson out of the day. The problem with some of the puzzles (most, I daresay) is that they don't apply in 99.99% of the games you play. Some of them you have to be in that EXACT position to really get anything out of it, in the long term. But it does help you look for things you have never seen before. For me it has taught me when to make a sacrifice, for example, to sac a rook for a bishop. I never even considered it before, but now I am looking for ways like that to make my position better. Because of chess mentor I now look for better ways to improve my position. In fact, I would much rather have a good position then be up in material. I had an opponent that was ahead a full rook for 10 moves, but I ended up destroying him because of his weak kingside. Things like this you'll eventualy catch on.

But if you really want to get better and improve, here's what you do: You lose games. I'm not recommending this on purpose, but you learn a lot from lost games. You learn what things you should have taken advantage of but decided not to... and also, in my case, it will tell me that I should not have been so recklessly aggressive. (I play aggressively, open position, and love queenside castling in order to full on assault the other players kingside).

If you are a free member on chess.com, which I assume from the information you have given, I recommend playing as many tactics trainer and chess mentor puzzles that it will let you. (normally about 6 total). But best yet is to play against other players. Dont just play against fellow players who are the same skill level and rating as you. Play against players who are rated much higher. They will teach you a lot when you lose. Play against lower rated players. they will teach you how to better find holes in their positions because almost all lower rated players have the same Achilles Heel: weak pawn structures.

Good luck and I hope you won't hestitate to contact me if you need any more help or just want to play a game. I like analyzing games with the player afterwards whether I've won or not.

Ryan @datfreshmandude

# Answer
> 2 votes
Like Ryan Orr I too am a free member of Chess.com. I love the site and it has been very useful to my chess learning! You are right in saying that getting a coach of sorts would be more beneficial to you. However Chess.com has many useful resources (developed by GMs) for their members to use. Tactics trainer and Chess mentor are the only real learning tools "fully" accessible to free member. Limited to 3 tactics per day, only the free trials for the mentor. So it would be worth your while to get some sort of paid membership. The price is up to you but I would agree with you to take advantage. There is another feature available to the free member that starts you from a position and lets you play against a computer and try and win. Use that as well!

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Tags: online-chess
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# Question
Title: Could you show me the code(s) of one or more simple chess program(s) written in C#?
I am a novice in C#.
I am looking for the code(s) of one or more chess program(s) written in C#.
Preferably, the code(s) should be short, clean, straightforward, very simple, and use only basic things (try to avoid complicated system namespace / library). It does not matter if the program is not very strong.
If you could also provide some explanations of the different parts of the code it would be even better.

The part of the code which interests me the most is the part which stores all the many millions positions at different depths.
Can this be done in a multidimensional array?
I was thinking that maybe the first two dimensions of the array could represent the two-dimensional boards, the 3rd dimension of the array could represent all the possible positions at a depth of 1 ply, the 4th dimension of the array could represent all the positions at a depth of 2 plies, the 5th dimension of the array could represent all the positions at a depth of 3 plies, etc... But perhaps that would be a little too messy.

# Answer
> 3 votes
Although it is written in C, you might want to take a look at Tom Kerrigan's Simple Chess Program (TSCP) which is created for this very purpose—to allow beginners to see what a simple chess engine is made of.

# Answer
> 3 votes
There is http://sharpchess.com/

And http://www.codeproject.com/Articles/36112/Chess-Program-in-C

But since chess engines are very cpu intensive and carefully tweaked for performance, if you want to do anything serious, you'd rather move to C/C++ as your implementation language.

And dont forget the wiki for chess programming: https://chessprogramming.wikispaces.com with many documented advanced techniques in the field.

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Tags: engines, programming
---


# Question
Title: Is a DGT Bluetooth Wireless e-Board stable enough to use regularly?
I am considering purchasing a DGT Bluetooth Wireless E-Board for my school's chess club for exhibition games to be broadcast to a room without having everyone hovering over the board.

Are these boards sufficiently stable and reliable that, once configured, they can be used weekly without requiring any expert attention? I'm thinking both of the ability to detect what pieces have been moved and also the reliability of the Bluetooth connection.

# Answer
Bluetooth supports distance of less than 30 feet, or 10 meters, and 802.11b is roughly up to 200 feet, though both distances depend on a number of factors; mention WiFi since it's possible that might be a better solution for your needs. Here's the DGT manual for "Connecting your Bluetooth board to your Computer", which might provide additional information of value to you.

Also, it appears that the DGT boards do have problems, here's an example; note the pawn falls, and the screen does not report the pawn is not where it is suppose to be; note that the board is not the Bluetooth model, though in this case, I don't believe it matters; also, it's possible this is not a hardware issue, but related to the software used in the demo I've linked to just now.

Given that the board appears to be $1000+, it's unlikely you're going to find enough reviews to judge if it's a good fit for your needs. My suggestion would be to make sure that you're 100% sure it's possible to return it at near to no cost given the price of the board.

While not a review of the Bluetooth model, here's a review of a DGT board that appears to use the same technology, minus the Bluetooth.
> 4 votes

# Answer
I just posted a review of the DGT board on Amazon. The software related to the DGT boards is VERY UNSTABLE and crashes too often to make them usable in practical play. Here is a link to the review, but ultimately here is what I said also:

URL: http://www.amazon.com/gp/product/B003M88VKS#customerReviews

A friend and I both have the DGT board and while the board and chess pieces appear to work fine, we have tried to get the related software drivers and ICC.com and PlayChess.com to cooperate. We have failed and have sent logs to DGT support for anwers after having done everything they recommended and installed latest drivers and software. The physical boards seem generally fine but the software does not work well (stability) across the internet sites ICC.com and playchess.com. We are only able to get through a game or a fraction of the game before all stops working. The boards seem stable if you play Fritz locally, but considering our goal was to play each other via the Internet, and not just play a computer locally, the DGT boards so far has not been a good investment. Be aware that they probably work fine locally on your computer but not very well across the Internet in their current release of software as of the time of this post. We are still actively sending logs and working with DGT support to try and improve the situation, but no luck. We have tried 4 computers, Windows 7 32 bit and 64 bit so far, and loaded all their latest drivers etc. We are greatly disappointed so far. We also wish chess.com would support the DGT board in the future, but that is an aside, but be aware chess.com is not supporting the DGT board so far also.
> 2 votes

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Tags: chess-clocks
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# Question
Title: Should I be afraid of the Slav Tolush-Geller Gambit?
As Black, after 1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3, I like to play 4... dxc4 5. a4 Bf5, but I am afraid to play 4... dxc4 because of 5. e4, the Tolush-Geller Gambit (always followed by 5... b5 6. e5 Nd5 7. a4 e6)

```
  [StartPly "9"]

  [FEN ""]
  1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 dxc4 5. e4 b5 6. e5 Nd5 7. a4 e6 (5. a4 Bf5)

```

I am a 1800 Elo player who likes quiet and strategic positions, so this gambit which leads to insanely sharp tactical positions is frightening me...

But is this gambit really sound?
Does it really give White enough compensation for the sacrificed Pawn?
Should I really be afraid of it?
Should I really abandon 4... dxc4 because of this gambit and choose something else instead (maybe 4... a6 the Chebanenko)?

# Answer
It is quite sound in my opinion. As White I always welcome `dc`: Black surrenders the center, and asserting a control over it is well worth the pawn. I am not so much sure about 6. e5 though.
> 2 votes

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Tags: opening, gambits, slav-defense
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# Question
Title: What are the options to automatically identify games where the first move played was the best by a margin?
Let's imagine I have a pgn file with each game starting from a tactical position, and I want to identify the games where the solution was the only one. Basically an engine would have to evaluate several possible moves, and the evaluation margin between the first best move and the second best move would have to be above a certain threshold (e.g. \>3.00 pawns). I do not want to load up manually every game and look at the engine evaluation - that's the step I am hoping to eliminate.

I am interested to hear of any GUI based solutions, or even script based (e.g. modifications to this - http://sourceforge.net/p/scid/mailman/message/29220017/ \- I like this script, but can't get it up and running easily because SCID TCL interpreter on Windows seems to come without Expect package ...)

# Answer
It is not too difficult to do this with a python script: You basically start the engine as a subprocess and communicate via "uci". I'll post some not very pretty code snippets and try to explain what you have to do:

```
engine=subprocess.Popen('./stockfish-5-        64',universal_newlines=True,stdin=subprocess.PIPE,stdout=subprocess.PIPE,)

def put(command):
    print command
    engine.stdin.write(command+'\n')

    if command!='quit':
        engine.stdin.write('isready\n')
        while(True):
            text=engine.stdout.readline().strip()
            print
            print text
            print
            if text == 'readyok':
                return

def get():
    engine.stdin.write('isready\n')
    while(True):
        text=engine.stdout.readline().strip()
        print text
        if text == 'readyok':
            break
        if text !='':
            print text

def getResult(depth):
    Result=[]
    while(True):
        text=engine.stdout.readline().strip()
        liste=text.split()
        if text[:22]=="info depth "+str(depth)+" seldepth" and liste[15]=='1':
            Result=[]
        if text[:22]=="info depth "+str(depth)+" seldepth":
            Result.append(text)

        if text[:8] == 'bestmove':
            break

    Scores=[]
    for line in Result:
        liste=line.split()
        Scores.append(liste[7])

    return Scores

def Game_Analysis(game):
    scorestring=''
    moves=''
    for x in range(len(game)-1):
        moves+=game[x]+' '
        command='position startpos moves '+moves
        put(command)
        get()
        put('go depth 15')
        Scores=getResult(15)
        for score in Scores:
            scorestring+=score+' '
        scorestring+='\n'
    return scorestring

get()
put('uci')
get()
put('setoption name MultiPV value 20')
get()

print Game_Analysis(game)

put('stop')
put('quit')

```

So, get() and put() are for communicating with the engine.

put('uci') starts the dialog.

put('setoption name MultiPV value 20') tells the engine to return the best twenty moves. (In your case you really only need 2)

command='position startpos moves '+moves
put(command) This sets up the position, unfortunately the moves aren't pgn but in uci-format. So you'll probably have to transcribe or use FEN.

In GetResult() I extract the 20 best scores of the position. Then you only need to look for a big difference between move one and move two.

Game\_Analysis(game) extracts the 20 best scores for every position in a game, here given as a list of uci-formated moves.

To deal with the uci-format and really understand these commands you should have a look at the uci=Universal Chess Interface.
> 2 votes

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Tags: engines, software, pgn
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title: Awkward situation. Take it or leave it!

text:
# Question
Title: Awkward situation. Take it or leave it!
Imagine a situation where our queen, opponent's bishop and opponent's king are in same vertical line such that if bishop was not there, there would be a check. Now the opponent, somehow unnoticeably removes the bishop from the line which straight leads to our victory. . . So is this a fouls and should be reversed or a rule or something?? Answer please,!!!

# Answer
This depends on the rules you are playing under:

In blitz chess with very short time control, an illegal move, such as putting your king into check, usually loses.

In Fide rated tournament games only the second illegal move loses, so he would just have to put the bishop back and make a different move with the bishop (such as taking your queen …).

In olden times there was the rule that you'd have to take back an illegal move and make a king move instead, as a way of punishment, because quite often making a king move would just be a loss of time. I think this is a good compromise for casual games.

I remember an anecdote about this old rule: Two masters were playing and after 2…Qd5 white wanted to attack the queen with 3.Nc3. But he fumbled the piece and played 3.Bc3 instead.

The king move punishment unfortunately led to immediate mate …

```
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
1.e4 d5 2.exd5 Qd5 3.Ke2 Qe4#

```
> 3 votes

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Tags: analysis
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