# Question
Title: When is it legal to castle moving the rook first?
As a follow on from the question *Is it legal to castle with a "ghost" rook*: When is it legal (according to the FIDE Laws of Chess) to castle moving the rook first?

# Answer
> 12 votes
The 2019 Champions Showdown: Chess 9LX (aka Chess 960) currently taking place in St. Louis should have been a clue.

Here is the relevant extract from the FIDE Laws of Chess:

> **Guidelines II. Chess960 Rules**
>
> **II.3 Chess960 castling rules**
>
> II.3.1 Chess960 allows each player to castle once per game, a move by potentially both the king and rook in a single move. However, a few interpretations of regular chess rules are needed for castling, because the regular rules presume initial locations of the rook and king that are often not applicable in Chess960.
>
> II.3.2 How to castle. In Chess960, depending on the pre-castling position of the castling king and rook, the castling manoeuvre is performed by one of these four methods:
>
> II.3.2.1 double-move castling: by making a move with the king and a move with the rook, or
>
> II.3.2.2 transposition castling: by transposing the position of the king and the rook, or
>
> II.3.2.3 king-move-only castling: by making only a move with the king, or
>
> II.3.2.4 **rook-move-only castling: by making only a move with the rook**.

Here is one of the starting positions from yesterday's games which gives the possibility of rook-only castling on the queenside:

```
[fen "nrkrqbbn/pppppppp/8/8/8/8/PPPPPPPP/NRKRQBBN w KQkq - 0 1"]

```

The kings are already on the queenside castling squares of c1 and c8. All that is required is for the d file rooks to move and castling can be performed by hopping the b rook over the king.

# Answer
> 23 votes
Unless this is a trick question, I'd say **never**:

> 3.8.2 \[\] This is a move of the king and either rook of the same colour along the player’s first rank, counting as a single move of the king and executed as follows: the king is transferred from its original square two squares towards the rook on its original square, then that rook is transferred to the square the king has just crossed.

The word **then** implies the king moves first, and the rook second. Also,

> 4.4 If a player having the move:
>
> 4.4.1 touches his king and a rook he must castle on that side if it is legal to do so
>
> 4.4.2 deliberately touches a rook and then his king he is not allowed to castle on that side on that move and the situation shall be governed by Article 4.3.1

That would imply that touching both king and rook (but not moving them) commits the player to castling; then, he/she could then move the rook first and only then the king, since that would give the same position on the board as the only legal play at that moment. Still, if I would see that as an arbiter, I'd have a word with the player about this.

# Answer
> -3 votes
I think this is a bogus question. For the King to be in that position it must have already moved, so therefore cannot be allowed to castle. A standard rule is that if a player wishes to castle then the King must be moved first. By moving it 2 squares, which is an illegal move, the player is indicating that they wish to castle. If the rook is moved first then it could be that they're keeping their options open as to whether to castle or not.

---
Tags: rules, castling
---


# Question
Title: How does a single player have 2 different FIDE accounts
When searched **Yu, Yangyi** you get 2 results. One is the top Chinese super GM. The other is an unrated player with Blitz rating 2544. Both have different Birth days according to FIDE but when I checked the unrated Yu Yangyi's history, It showed that he has played only 1 event which is `2012 Asian Team Chess Championship Men - Blitz`. This confirms that this is the Super GM Yu Yangyi. https://chess-results.com/tnr73636.aspx?lan=6&art=20&snr=4

How is this possible to get a seperate FIDE ID when you already have one. In that case can he register to a tournament with his unrated account

# Answer
> 5 votes
> How is this possible to get a separate FIDE ID when you already have one?

Unfortunately FIDE do not have proper data validation for these things. For instance, check out Lawrenson, Conor. This baby prodigy has been registered by FIDE as a chess player even though his birth year is 2022!

When Yu entered the Asian team championships in 2012 the arbiter's job was to enter his name and ID successfully in the pairing program. If he didn't do this and also entered a wrong date of birth then when the tournament results were sent to the China international rating officer they would have put the file through a program which would automatically generate a new FIDE Id for unregistered players. It would only throw an error if the name and date of birth were identical.

The quality of FIDE data has actually improved over the years. It was much worse, particularly pre 2001. Check out the early records of my club mate Dave Walker in Olimpbase. Surprisingly the records suggest that he/she got their first FIDE rating in January 1982 of 1845. Dave's sex is recorded as "W". He has the same rating and sex in the next list in July 1982 followed by 8 lists in which there is "no data available" for Dave before he re-emerges as a man in the January 1987 list with a rating of 2285. Obviously the transition was so successful that it came with 440 points of rating gain!

As somebody who has known Dave for more than 40 years I can tell you that he has always been a man, except when he was a boy :-). What happened becomes clear if we look at the FIDE records for Susan Walker in Olimpbase. Her first rating was 1885 in January 1983, the first list which records "no data" for Dave Walker. Dave Walker never was a woman. It is just that FIDE confused him with Susan Walker.

Note that Susan Walker went on to marry Keith Arkell and so become Susan Arkell. During the time she was married to Keith FIDE introduced IDs and the immediate data integrity benefit was seen when she divorced Keith and married Bogdan Lalic. FIDE were now clever enough to know that Susan Arkell and Susan Lalic were the same person. However they don't "know" that that person is the same as Susan Walker.

> In that case can he register to a tournament with his unrated account?

It depends if he gives the correct information and if the arbiter is paying attention when he/she enters the information into the pairing program. If the arbiter makes another mistake then it could happen.

---
Tags: fide, rating, tournament, elo, tournament-directors
---


title: Game databases with spent time listed?

text:
# Question
Title: Game databases with spent time listed?
I refereed a match where White had a rather large time advantage in the middlegame - on all boards. This isn't that remarkable, I expect that Black must invest more time just to equalize, and often must defend, which takes more time too. But already in the next match the n=8 stat flew out of the window.

Are there any large game databases (n=1000 surely is a minimum to decide about my hypothesis) which also record the time spent for each move? Note that I'm talking about tournament mode games, although the postulated effect might show up in rapid chess too.

# Answer
There are a lot of games in chess.com with clock info on every move. This clock info can be used to calculate the time spent per move. It can be tricky for time control with periods as additional time is added after say 40 moves. Also there are games with weird clk information in this case just ignore such games.

Go to chess.com events at https://www.chess.com/events, select events and download the event's pgn file
> 1 votes

---
Tags: database, time-management
---


title: Chess.com ELO weirdness

text:
# Question
Title: Chess.com ELO weirdness
I was rated 1140 in rapid, playing against an 1145. Chess.com said 8 points were at stake, so a win for should put me at 1148 and my opponent at 1137. I won and my ELO did become 1148, but my opponent's became 967. What happened here? That's a 178 point swing, over 20x what it should have been.

# Answer
Chess.com does not exactly use elo ratings. The system they use is glicko2. This involves a "ratings deviation" variable. If your RD is low, your rating is considered reliable. The result is that your rating won't change as much, but your opponent's rating will change more. Conversely, if your RD is high, then your rating is considered unreliable. So when you play, your rating will change more, but your opponent's rating will change less.

RD starts out at a high value and will lower as the system becomes more confident as to what your ability is. It will increase if you go a while without playing games, since your ability might have changed in the meantime.

So, the most likely explanation is that your RD is low, and your opponent's RD was high. RD doesn't seem to be displayed in your stats anymore like it used to be, but there *is* a way to check it if you're interested. Go to this page:

https://api.chess.com/pub/player/msoliver/stats

Replace "msoliver" with the username of the player you're interested in. It's not exactly a user-friendly page, but it does show the RD for all your ratings.
> 6 votes

# Answer
It also depends on the rating deviation of players.

Created an online glicko2 program where you can input your rating info and opponent's rating info. This can be used to approximate the changes in the rating after applying the results.
> 0 votes

---
Tags: online-chess, elo
---


# Question
Title: What if white can't capture before black?
Imagine a variant of chess with the simple rule: it is illegal for white to play any capturing move before black has captured a piece. Check/checkmate is unaffected. And white can lose by being checked in a way where the only escape would be to capture a piece.

For instance, this wins for black:

```
[FEN ""]
1. f4 c6 2. Nf3 Qb6 3. Nc3 Qf2+

```

(Arguably, that's 3..Qf2#)

Question: How big is the advantage for black? Is there a forced win?

# Answer
It looks like Black has a decisive advantage.

Obviously Black will avoid making any capture unless that gives her a decisive advantage normal-chess-wise. Meanwhile she can advance all her piece without fear of losing them.

White must be careful about his king safety: any open square in its vicinity is an invitation for a lone queen mate like ...Qf2# in OP's example, but surrounding it make it vulnerable to smothered mates (or decisive forks) by knights... But his queen will also be very vulnerable to Black's minor pieces !

A simple plan for Black would be to develop everything on active squares, whether White control them or not: e5,d5,Nf6-e4,Nc6-d4,Bf5/g4,Bc5/g4,0-0,Q-somewhere, say Qf6 or Qh4, bring the rooks as well if need be. All without captures, or course. And look for opportunities of any Q-check, N-check, B or N attacks against the wQ. I have no big advice for White beside keeping a tough formatiopn (but with Q-mobility!), occupying squares where the opponent wants to go, and hope for a mistake or a premature capture...

Playing several games with that rule (either between humans or engines) would help have a better feeling of the subtelties it creates, and probably settle the matter.

An idea to make the game less unbalanced (still advantageous for Black yet) would be to allow White to capture a checking piece, or even to allow all captures after the first check of the game is delivered.
> 2 votes

---
Tags: chess-variants
---


# Question
Title: Which legal positions with White to move are also legal with Black to move (if colours and board are flipped)?
For every reachable position, is the equivalent position for black also reachable?

If so, can you prove it?

If not, which reachable positions for white are not reachable for black and why?

Definitions:

* **position**: includes castling and en passant possibilities, excludes 50-move considerations
* **equivalent position for black**: swap the colours of all pieces, flip the pieces vertically (swapping rank 1 pieces with rank 8 pieces etc), swap whose turn it is to move, castling rights and e.p. ability. (e.g.: the equivalent position for black after 1.e4 would be the starting position, but with black's E pawn on e5 and with white to move, both players able to castle both sides).
* **legal**: it's possible to get to this position by some sequence of legal moves (disregarding 50 move rule)

# Answer
It's perhaps easier to understand the set of those positions whose flipped versions are *not* reachable. Suppose all the following are true:

* all pawns, rooks, bishops and knights are on the board
* the a and h pawns have not moved more than one square; the other pawns are at home
* the bishops are at home

Then no bishop or queen has ever moved, and every move has been from a black square to a white square or vice versa. White starts with 8 units on black squares (four pawns, Ra1, Bc1, Ke1 and Ng1). Later, if this count is even, White has made an even number of moves; if odd, odd. The same can be said of Black units on white squares. The sum of these two numbers is the total number of White and Black moves made so far. This total's parity (i.e. whether it's even or odd) determines whose turn it is to move: even, White's turn; odd, Black's turn.

Now flip the position. The total is the same. Therefore the *same player* must have the move. Thus if, as you require, we must also swap whose turn it is to move, then the resulting position is unreachable.

By contrast, if anything else has happened, one or other player can "lose a move" and enable the flipped position to occur. For example, given that we may play into a Sicilian with White to move, by 1 e4 c5, we may also play into a reversed Sicilian with Black to move, by 1 c3 e5 2 c4. Another example: given that we may play into a Indian with White to move, by 1 d4 Nf6, we may play into a reversed Indian with Black to move, by 1 Nf3 d6 2 Ng1 d5 3 Nf3.

Thanks to Steve Bennett for the idea which leads to the following additional positions. Suppose that at least one of the players retains at least one castling-right, their f-pawn has advanced one square, and (except for the f-pawn) the above conditions all hold. Now flip the position. The only way to reach the flipped board position with the other player to move is to change the parity of the number of moves, by moving this other player's king out via the f-file. But moving their king destroys both their castling-rights, so the position is different.
> 5 votes

# Answer
Alternate set of unflippable positions (inspired by Lord Dunsany's chess problem):

One side has the b-g pawns, both bishops, the king and queen all on their original squares.

The rotated version of this position is not possible because the pawns and bishop prevent the king and queen from moving, yet they're on the wrong squares.
> 0 votes

---
Tags: puzzles
---


# Question
Title: Is it sportsmanlike to waste opponents' time by giving check at the end of the game?
In Blitz games, with very little time left for both players, is it acceptable to keep on checking the opponent and waste their time and win the game on time? Is that true sportsmanship?

# Answer
That only works in blitz time controls with no increment. If you accept games with no increment you are basically agreeing that flagging is part of the game and sportsmanlike. If you personally find it unsporting then always play with an increment and decline challenges with no increment.
> 86 votes

# Answer
In blitz, time is a major factor in the game, and it is fine to try and win on time.

If you used too much time, and your opponent thinks he can flag you, there is nothing wrong with that. It is part of the game.
> 50 votes

# Answer
Time is a resource in blitz chess, as much as or even more so than material. If it isn't unsportsmanlike to capture your opponent's material, how is it unsportsmanlike to capture their time?

In blitz chess, there is often a time-endgame. Otherwise pointless checks and random-looking moves are part of this endgame. From my perspective, this is part of what makes blitz *fun*. I have lost many blitz games because my opponent found ways to make me burn precious seconds responding to annoying checks at the end of the game, and have never thought of them as bad players for doing so.
> 42 votes

# Answer
> waste their time

If it's clear that they are able to win within the time they have left, this could be considered bad sportsmanship. However, in those situations the number of remaining checks is usually quite low.

> win the game on time

If that's a possibility, I'd say it's perfectly fine to play on if you're losing on the board. At the beginning of the game, both players get the same amount of time to **finish the game**, not just to **obtain a winning position**. Time management is an important part of the game, and if you fail at it, you deserve as much to lose as you do with failing to obtain a good (or drawn) position.
> 29 votes

# Answer
# Absolutely!

If time wasn't a key to the style of match, it wouldn't be timed.

Adding a time constraint to an otherwise purely strategic game strongly suggests that the time component will and should be used 'strategically' as well.
> 9 votes

# Answer
While flagging the person is not the best and nicest way to beat the opponent (the opponent will probably rage abit), playing a blitz game, **especially** the 3+0 blitz games, you are indirectly telling your opponent that the you are possibly going to be flagged down on time, especially when one is losing, and time is the only option to win on. Flagging is a part of chess, and it is completely fine. Of course, if you are losing by an entire queen and your opponent has a reasonable amount of time, resigning is the most courteous option. But if you were in a drawn position, where the opponent had less than 10 seconds, it's completely fine to flag him/her.
> 1 votes

---
Tags: check, blitz, time-management, ethics
---


# Question
Title: Does opening preparation contribute a lot in winning games?
It is often said that ***Opening preparation is considered one of the most vital things a chess player needs to learn when they start getting better(above 2000 elo)***. Many chess players are known for their good opening preparation like Garry Kasparov, Fabiano Caruana, Anish Giri, Hikaru Nakamura, MVL, etc. Most GMs prepare a lot of openings with different lines, and variations for their classical tournaments. Still, many are not able to get a win and reach the top.

I have never heard anyone say that Magnus Carlsen is very good at opening preparation. He's often regarded as a great endgame player, having good intuition.

So, my question now follows: Is opening preparation really effective and contributes a lot to win at the very top level? Or being a good endgame player, in which good intuition is better? If yes, then why do most of the players spend time in preparation? If not, then why can't they win most of their games by outplaying their opponent?

**To make it more clear and easy to understand:** I want to know if preparation is worth it compared to the time many titled players put into it.

# Answer
Especially for high-rated players like titled players, **YES** opening preparation is crucial. Without it, you would lower your win rate by *a lot*.

Opening preparation is not everything though, you still need to prepare middlegame and endgame positions and theory, as well as certain positions where one can exploit weakness (mostly in openings though).

The saying "Opening preparation is considered one of the most vital things a chess player needs to learn when they start getting better(above 2000 elo)" is not wrong, as especially for me, I am stuck at 2000 blitz rating on lichess.org, as I do not do opening preparation, which of course results in my rating not increasing at all anymore.

Having good intuition is probably a combination of general theory and positions of chess and the ability to see many moves into the future, but it not necessary that opening preparation or intuition is better. In my opinion, I think both are equally good.

Most players still lose even though they have prepared a lot on openings, either because the opponent played a move that completely confused the opponent in the opening, or missed an incredibly good move for either the opponent or yourself.

If you do not plan to study much on openings (Magnus Carlsen still studied *a lot* more than normal people) and rather have good intuition, intuition is quite tricky to train for in the first place, so in my opinion, studying openings is slightly better.

I do not know what others think of this, but in my opinion, it is quite worth it to grind and study openings, especially after a long period of time. Doing so will lead to noticeable better play in the opening. However, if you are the type of person that does not really like long-term studying, i'd rather you study a little only, and gradually build up your knowledge over time. Obviously these GM's got their titles when theyre quite young, so they studied quite intensely on theory, especially openings, to achieve the high rating they have today.
> 2 votes

---
Tags: opening, strategy, learning, preparation
---


# Question
Title: How many moves to checkmate in the initial position with all Black pieces captured?
From the above position, black player lost (by mistakes) all of its pieces after his 15th move. How many more moves shall the black king have before it is checkmated by white if it is black' move?

# Answer
It's a mate in 6. (EDIT: I was reminded Black is to move, but it is still #6 on any defense, if I checked correctly.) Stockfish can tell you, and any problem chess program can tell you exactly. For the lulz, here is the complete output of "Popeye" with the threat (White to move). tl;dr: Only 1.e4 mates in 6, which I remembered correctly, since this is a well-known chess problem.

```
   1.e2-e4 ! threat:
      2.Qd1-g4 threat:
              3.Qg4-g7 threat:
                      4.Bf1-b5 +
                          4...Ke8-d8
                              5.Qg7-d7 #
                  3...Ke8-d8
                      4.Bf1-a6 zugzwang.
                          4...Kd8-e8
                              5.Ba6-b5 +
                                  5...Ke8-d8
                                      6.Qg7-d7 #
                              5.Ba6-c8 zugzwang.
                                  5...Ke8-d8
                                      6.Qg7-d7 #
                      4.Bf1-b5 threat:
                              5.Qg7-d7 #
                          4...Kd8-c8
                              5.Bb5-c6 zugzwang.
                                  5...Kc8-b8
                                      6.Qg7-b7 #
                                  5...Kc8-d8
                                      6.Qg7-d7 #
                              5.Qg7-a7 zugzwang.
                                  5...Kc8-d8
                                      6.Qa7-d7 #
          2...Ke8-f7
              3.Qg4-d7 +
                  3...Kf7-g6
                      4.d2-d4 threat:
                              5.Qd7-e7 zugzwang.
                                  5...Kg6-h5
                                      6.Qe7-g5 #
                          4...Kg6-h5
                              5.Bf1-c4 zugzwang.
                                  5...Kh5-g6
                                      6.Qd7-f7 #
                                  5...Kh5-h4
                                      6.Qd7-h3 #
                              5.Qd7-f5 +
                                  5...Kh5-h4
                                      6.Qf5-h3 #
                                      6.Qf5-g5 #
                                      6.g2-g3 #
                                      6.Sg1-f3 #
                              5.Qd7-e6 zugzwang.
                                  5...Kh5-h4
                                      6.Qe6-h3 #
                              5.Qd7-h7 +
                                  5...Kh5-g4
                                      6.Qh7-h3 #
                                      6.h2-h3 #
                                      6.f2-f3 #
                                      6.Bf1-e2 #
                              5.Qd7-g7 threat:
                                      6.Qg7-g5 #
                          4...Kg6-f6
                              5.Bf1-c4 threat:
                                      6.Qd7-f7 #
                  3...Kf7-g8
                      4.b2-b4 threat:
                              5.Bf1-c4 +
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                  5...Kg8-h8
                                      6.Bc1-b2 #
                          4...Kg8-f8
                              5.Bc1-b2 zugzwang.
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                          4...Kg8-h8
                              5.Bc1-b2 +
                                  5...Kh8-g8
                                      6.Qd7-g7 #
                      4.b2-b3 threat:
                              5.Bf1-c4 +
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                      6.Bc1-a3 #
                                  5...Kg8-h8
                                      6.Bc1-b2 #
                          4...Kg8-f8
                              5.Bc1-b2 zugzwang.
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                          4...Kg8-h8
                              5.Bc1-b2 +
                                  5...Kh8-g8
                                      6.Qd7-g7 #
                      4.d2-d4 threat:
                              5.Bc1-h6 threat:
                                      6.Qd7-g7 #
                      4.d2-d3 threat:
                              5.Bc1-h6 threat:
                                      6.Qd7-g7 #
                  3...Kf7-f6
                      4.d2-d4 threat:
                              5.Bf1-c4 threat:
                                      6.Qd7-f7 #
                          4...Kf6-g6
                              5.Qd7-e7 zugzwang.
                                  5...Kg6-h5
                                      6.Qe7-g5 #
                      4.d2-d3 zugzwang.
                          4...Kf6-e5
                              5.Qd7-c6 threat:
                                      6.Sg1-f3 #
                              5.Qd7-e7 +
                                  5...Ke5-d4
                                      6.Qe7-d6 #
                                      6.c2-c3 #
                                      6.Sg1-f3 #
                                      6.Sg1-e2 #
                                      6.Bc1-e3 #
                          4...Kf6-g6
                              5.Qd7-e7 zugzwang.
                                  5...Kg6-h5
                                      6.Qe7-g5 #
                  3...Kf7-f8
                      4.Sg1-h3 zugzwang.
                          4...Kf8-g8
                              5.Sh3-g5 zugzwang.
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                  5...Kg8-h8
                                      6.Qd7-h7 #
                      4.Sg1-f3 zugzwang.
                          4...Kf8-g8
                              5.Sf3-g5 zugzwang.
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                  5...Kg8-h8
                                      6.Qd7-h7 #
                      4.b2-b4 threat:
                              5.Bc1-b2 zugzwang.
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                          4...Kf8-g8
                              5.Bf1-c4 +
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                  5...Kg8-h8
                                      6.Bc1-b2 #
                      4.b2-b3 threat:
                              5.Bc1-b2 zugzwang.
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                          4...Kf8-g8
                              5.Bf1-c4 +
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                      6.Bc1-a3 #
                                  5...Kg8-h8
                                      6.Bc1-b2 #
                      4.d2-d4 threat:
                              5.Bc1-h6 +
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                      4.d2-d3 threat:
                              5.Bc1-h6 +
                                  5...Kf8-g8
                                      6.Qd7-g7 #
          2...Ke8-f8
              3.Bf1-b5 zugzwang.
                  3...Kf8-e7
                      4.Qg4-g6 zugzwang.
                          4...Ke7-f8
                              5.e4-e5 zugzwang.
                                  5...Kf8-e7
                                      6.Qg6-e8 #
                                      6.Qg6-f6 #
                          4...Ke7-d8
                              5.Qg6-d6 +
                                  5...Kd8-c8
                                      6.Bb5-a6 #
                  3...Kf8-f7
                      4.e4-e5 zugzwang.
                          4...Kf7-e7
                              5.Qg4-f5 threat:
                                      6.Qf5-f6 #
                                  5...Ke7-d8
                                      6.Qf5-d7 #
                          4...Kf7-f8
                              5.Qg4-g6 zugzwang.
                                  5...Kf8-e7
                                      6.Qg6-e8 #
                                      6.Qg6-f6 #
              3.Qg4-d7 threat:
                      4.Sg1-h3 zugzwang.
                          4...Kf8-g8
                              5.Sh3-g5 zugzwang.
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                  5...Kg8-h8
                                      6.Qd7-h7 #
                      4.Sg1-f3 zugzwang.
                          4...Kf8-g8
                              5.Sf3-g5 zugzwang.
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                  5...Kg8-h8
                                      6.Qd7-h7 #
                      4.b2-b4 threat:
                              5.Bc1-b2 zugzwang.
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                          4...Kf8-g8
                              5.Bf1-c4 +
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                  5...Kg8-h8
                                      6.Bc1-b2 #
                      4.b2-b3 threat:
                              5.Bc1-b2 zugzwang.
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                          4...Kf8-g8
                              5.Bf1-c4 +
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                      6.Bc1-a3 #
                                  5...Kg8-h8
                                      6.Bc1-b2 #
                      4.d2-d4 threat:
                              5.Bc1-h6 +
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                      4.d2-d3 threat:
                              5.Bc1-h6 +
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                  3...Kf8-g8
                      4.b2-b4 threat:
                              5.Bf1-c4 +
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                  5...Kg8-h8
                                      6.Bc1-b2 #
                          4...Kg8-f8
                              5.Bc1-b2 zugzwang.
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                          4...Kg8-h8
                              5.Bc1-b2 +
                                  5...Kh8-g8
                                      6.Qd7-g7 #
                      4.b2-b3 threat:
                              5.Bf1-c4 +
                                  5...Kg8-f8
                                      6.Qd7-f7 #
                                      6.Bc1-a3 #
                                  5...Kg8-h8
                                      6.Bc1-b2 #
                          4...Kg8-f8
                              5.Bc1-b2 zugzwang.
                                  5...Kf8-g8
                                      6.Qd7-g7 #
                          4...Kg8-h8
                              5.Bc1-b2 +
                                  5...Kh8-g8
                                      6.Qd7-g7 #
                      4.d2-d4 threat:
                              5.Bc1-h6 threat:
                                      6.Qd7-g7 #
                      4.d2-d3 threat:
                              5.Bc1-h6 threat:
                                      6.Qd7-g7 #
              3.Qg4-e6 threat:
                      4.Bf1-c4 threat:
                              5.Qe6-f7 #
                          4...Kf8-g7
                              5.d2-d4 threat:
                                      6.Qe6-h6 #
                                  5...Kg7-f8
                                      6.Qe6-f7 #
                                      6.Bc1-h6 #
                              5.d2-d3 threat:
                                      6.Qe6-h6 #
                                  5...Kg7-f8
                                      6.Qe6-f7 #
                                      6.Bc1-h6 #
                              5.Qe6-f7 +
                                  5...Kg7-h6
                                      6.d2-d4 #
                                      6.d2-d3 #
                                  5...Kg7-h8
                                      6.Qf7-g8 #
                      4.d2-d4 threat:
                              5.Bc1-h6 #
                          4...Kf8-g7
                              5.Bf1-c4 threat:
                                      6.Qe6-h6 #
                                  5...Kg7-f8
                                      6.Qe6-f7 #
                                      6.Bc1-h6 #
              3.Qg4-g6 zugzwang.
                  3...Kf8-e7
                      4.Bf1-b5 zugzwang.
                          4...Ke7-f8
                              5.e4-e5 zugzwang.
                                  5...Kf8-e7
                                      6.Qg6-e8 #
                                      6.Qg6-f6 #
                          4...Ke7-d8
                              5.Qg6-d6 +
                                  5...Kd8-c8
                                      6.Bb5-a6 #

```
> 1 votes

---
Tags: checkmate
---


title: Bishop vs Knight

text:
# Question
Title: Bishop vs Knight
I read in a book written by Fischer about piece values, and he said that a knight is worth 3 pawns, and a bishop is worth 3,25 pawns. I know that in closed positions knights are better, and I have also read in a Nimzovich book that a centralized knight and bishop have equal value.

So, while evaluating a position, how can I recognize when a bishop is better, or when a knight is better? I also saw that grandmasters like bishop pairs very much. What about knight pairs?

Do engines make this difference?

Does it depend on the number of the pawns in the center, or something like that? What factors establish which are better?

# Answer
Basically, what it comes down to is mobility.

In closed positions bishops are often hemmed in by pawn chains everywhere, whereas knights can slowly maneuver to a good outpost. But it isn't the closedness of the position that makes knights better in this case. Some closed positions are so cramped that even knights cannot jump anywhere useful. It is only that knights usually are more mobile than bishops in closed positions.

```

[FEN ""]
[Event "USSR Championship"]
[Site "Leningrad (RUS)"]
[Date "1956"]
[EventDate "1956"]
[Round "?"]
[Result "1/2-1/2"]
[White "Yuri Averbakh"]
[Black "Boris Spassky"]
[ECO "E75"]
[PlyCount "145"]

1. c4 Nf6 2. Nc3 g6 3. e4 d6 4. d4 Bg7 5. Be2 O-O 6. Bg5 c5
7. d5 Qa5 8. Bd2 a6 9. a4 e5 10. g4 Ne8 11. h4 f5 12. h5 f4
13. g5 Qd8 14. Bg4 Nc7 15. Bxc8 Qxc8 16. Nf3 Nc6 17. dxc6 bxc6
18. Nh4 Qe8 19. hxg6 hxg6 20. Qg4 Rb8 21. Nd1 Ne6 22. Ra3 Nd4
23. Rah3 Qf7 24. Bc3 Rfe8 25. R3h2 Qxc4 26. Nxg6 Re6 27. Bxd4
Rxg6 28. Qf5 Qe6 29. Qxe6+ Rxe6 30. Bc3 d5 31. f3 Rb3 32. Rh3
c4 33. Kd2 Rg6 34. Rg1 d4 35. Ba5 Bf8 36. Rg4 Rd6 37. Kc2 Rd7
38. g6 Rdb7 39. Be1 c5 40. Rgh4 Bg7 41. Ba5 c3 42. bxc3 Ra3
43. cxd4 exd4 44. Rxf4 Ra2+ 45. Kd3 Rb1 46. Rh1 Rxa4 47. Kc2
Rb5 48. e5 d3+ 49. Kxd3 Rxf4 50. Bc3 Rxf3+ 51. Ke4 Rg3 52. Kf4
Rxg6 53. Ne3 Rb8 54. Nf5 Rf8 55. Rh5 Re8 56. Ke4 Rg1 57. Rh3
Bf8 58. Kd5 Rd1+ 59. Ke4 Rc1 60. Kd5 Rd1+ 61. Ke4 Rd7 62. Nh6+
Bxh6 63. Rxh6 Rh7 64. Rg6+ Kf7 65. Rf6+ Ke7 66. Rc6 Kd7
67. Rxc5 Rh6 68. Kd5 Rb6 69. Ba5 Rb5 70. Rxb5 axb5 71. e6+
Rxe6 72. Kc5 Re5+ 73. Kb6 1/2-1/2

```

Take this famous game. At move 16 the position is quite closed, but the black knights are pretty unhappy anyway. White is about to build a strong attack on the kingside and the black knights just don't have the space to create some counterplay. So Spassky take the rather shocking practical decision to ditch one of his immobile knights for more space and a chance of counterplay. Notice how a few moves later the remaining black knight lands on the perfect outpost on d4.

To be mobile knights have to be positioned close to the centre. But in the centre pieces are vulnerable to (pawn-) attacks. Therefore it is very important for knights to have save, central outposts.

In the endgame the bishops often get a lot stronger than knights, if there are pawns on both sides of the board. The knights on the other hand love local weaknesses.

Bishop pairs are strong because together they can control a lot of squares. Knights don't complement each other as well. Often they are even rivals for the same outpost. That's why the knight pair isn't a factor.
> 8 votes

# Answer
These answers are very comprehensive. As food for thought I would only add three points that I haven't seen mentioned about the transitory (changing) value of the pieces during a game, and a caution against relying on the number values.

First, some have already noted how **bishops become more powerful in the ending** when their better mobility really gets to shine, but in the opening, Andrew Soltis notes in Rethinking the Chess Pieces that:

"a **knight is frequently more active, more threatening, in short, more significant than a bishop in the first ten or so moves of a game**. That may sound trivial but it is more than a quarter of a 40-move game."

a few paragraphs later he added:

"GM Gennady Timoshchenko studied a database of 150,000 games and came to the conclusion that **BxN often makes sense in the opening because a knight is simply the more useful piece then**. "A well-written chess program should be aware of the fact that at the beginning of the game the knight is at the peak' of its strength relative to the bishop and its relative strength decreases" from then on, he wrote in the \[CCA Journal, December 1993."

Conversely, and as alluded to in other replies, **bishops increase in relative value as the game goes on**.

Second, the value of minor pieces changes depending on captures, and on the presence of major pieces (and on pawn structure, as noted by others). Jose Capablanca wrote in A Primer of Chess that **a knight becomes weaker as pieces are traded off** (while rooks become stronger). Larry Kaufman added to this that the same holds true after pawn exchanges. GM Timoshchenko said a knight increases in value after a trade of rooks, and decreases in value after a trade of queens.

Another way of saying this is that the combination of Q+N and R+B are generally stronger in the endgame than Q+B and R+N. So in general in the ending having R+B \> R+N, while Q+B \< Q+N.

Finally, I would also caution against relying on the numbers too much in deciding which pieces are better. Expand your understanding of the position (and of chess) by using a more sophisticated approach endorsed by many chess teachers. Yusupov suggests using **the following five factors to determine the relative value of pieces** (relative to other pieces in an actual position):

1. Mobility
2. Activity
3. Coordination
4. Central location
5. Safety
> 5 votes

# Answer
Kasparov once said something like: "The number of positions in which a bishop is better a than knight is greater than the number of positions in which a knight is better than a bishop. That's why bishops are better than knights, in general".

As mentioned in other answers, general principle is that knights are usually superior in closed positions, where the advantage of being able to jump over pieces becomes more important than the long range bishops have.

Now, I am not a *very* good chess player, but I will give you *my* view on advantages and disadvantages of knights and bishops, and I will try to make it as concrete as possible. However "wrong" my views may seem to you (or objectively are), at least I hope it will be something for you to think about.

**What I like about bishops**:

* they can *simultaneously* play a defensive role and an attacking role;
* in an endgame (especially when there are only few pawns left, and not all on the same side of the board), bishop can be sacrificed "at the very last moment" meaning: you let your opponent spend a lot of moves to get her/his pawn(s) to the promotion square and then it disappears, all the while you use your bishop to nurse your pawn up the board; since knights are rather clumsy at stopping pawns alone, this is a significant factor around which one can make plans in an endgame; one of my favorite endgames ever is Fischer vs. Taimanov (excellently video-annotated here); the B vs N endgame appears on move 45;

```

[FEN ""]
[Event "Fischer - Taimanov Candidates Quarterfinal"]
[Site "Vancouver, Canada"]
[Date "1971.05.25"]
[EventDate "1971.05.16"]
[Round "4"]
[Result "1-0"]
[White "Robert James Fischer"]
[Black "Mark Taimanov"]
[ECO "B47"]
[WhiteElo "?"]
[BlackElo "?"]
[PlyCount "141"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Qc7 5. Nc3 e6 6. g3 a6
7. Bg2 Nf6 8. O-O Nxd4 9. Qxd4 Bc5 10. Bf4 d6 11. Qd2 h6
12. Rad1 e5 13. Be3 Bg4 14. Bxc5 dxc5 15. f3 Be6 16. f4 Rd8
17. Nd5 Bxd5 18. exd5 e4 19. Rfe1 Rxd5 20. Rxe4+ Kd8 21. Qe2
Rxd1+ 22. Qxd1+ Qd7 23. Qxd7+ Kxd7 24. Re5 b6 25. Bf1 a5
26. Bc4 Rf8 27. Kg2 Kd6 28. Kf3 Nd7 29. Re3 Nb8 30. Rd3+ Kc7
31. c3 Nc6 32. Re3 Kd6 33. a4 Ne7 34. h3 Nc6 35. h4 h5
36. Rd3+ Kc7 37. Rd5 f5 38. Rd2 Rf6 39. Re2 Kd7 40. Re3 g6
41. Bb5 Rd6 42. Ke2 Kd8 43. Rd3 Kc7 44. Rxd6 Kxd6 45. Kd3 Ne7
46. Be8 Kd5 47. Bf7+ Kd6 48. Kc4 Kc6 49. Be8+ Kb7 50. Kb5 Nc8
51. Bc6+ Kc7 52. Bd5 Ne7 53. Bf7 Kb7 54. Bb3 Ka7 55. Bd1 Kb7
56. Bf3+ Kc7 57. Ka6 Nc8 58. Bd5 Ne7 59. Bc4 Nc6 60. Bf7 Ne7
61. Be8 Kd8 62. Bxg6 Nxg6 63. Kxb6 Kd7 64. Kxc5 Ne7 65. b4
axb4 66. cxb4 Nc8 67. a5 Nd6 68. b5 Ne4+ 69. Kb6 Kc8 70. Kc6
Kb8 71. b6 1-0

```
* in general one could say that bishops are more useful in endgame pawn races;
* the movement of the bishop is more natural (straight diagonal lines), and therefore easier to use and to visualize; this makes them also better team players; you may heard people saying "a rook and a bishop is better than a rook and a knight"; it is easier to coordinate rooks and bishops, bishops and bishops, and especially queens and bishops, than knights,
* bishops can dominate knights more easily than vice versa.

**What I do not like about bishops**:

* when not paired, they are limited to one color of the squares (obviously, this is not optimal)
* you cannot win an endgame with an a- or h- pawn, if you have the wrong-colored bishop.

**What I like about knights**:

* each square on the board can be controlled by a knight;
* they can be "eternal" (there is a notion of an "eternal knight", i.e. in a situation knight vs. bishop, there is often a possibility of establishing an outpost for the knight, where it is untouchable and this is often the beginning of a long positional domination of the side with the eternal knight); one of my favorite games demonstrating this is Fischer vs. Bolbochan (excellently commented here); the "eternal knight vs. bad bishop" situation appears after move 20;

```

[FEN ""]
[Event "Stockholm Interzonal"]
[Site "Stockholm, SWE"]
[Date "1962.03.03"]
[EventDate "1962.??.??"]
[Round "21"]
[Result "1-0"]
[White "Robert James Fischer"]
[Black "Julio Bolbochan"]
[ECO "B90"]
[WhiteElo "?"]
[BlackElo "?"]
[PlyCount "74"]

1.e4 {Notes by Bobby Fischer} c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6
5.Nc3 a6 6.h3 Nc6 7.g4 Nxd4 8.Qxd4 e5 9.Qd3 Be7 {More accurate
is 9...B-K3 immediately.--Fischer} 10.g5 Nd7 11.Be3 Nc5 12.Qd2
Be6 13.O-O-O O-O 14.f3 Rc8 15.Kb1 {Amateurs are often puzzled
by this apparent loss of time. Actually it is a handy
defensive move, getting out of the pin on the QB-file which
could become annoying after ...P-QN4-5. One never knows when
lightning will strike! -- Fischer} Nd7 16.h4 b5 17.Bh3 Bxh3
18.Rxh3 Nb6 19.Bxb6 Qxb6 20.Nd5 {White has a strategically won
game; his Knight cannot be dislodged. -- Fischer} Qd8 21.f4
exf4 22.Qxf4 Qd7 23.Qf5 Rcd8 24.Ra3 Qa7 25.Rc3 g6 26.Qg4 Qd7
27.Qf3 Qe6 28.Rc7 Rde8 29.Nf4 Qe5 30.Rd5 Qh8 31.a3 h6 32.gxh6
Qxh6 33.h5 Bg5 34.hxg6 fxg6 35.Qb3 {The coup de
grace.--Fischer} Rxf4 36.Re5+ Kf8 37.Rxe8+ {Black
resigns. After 37...KxR; 38 Q-K6+, K-B1; 39 Q-B8+
mates.--Fischer} 1-0

```
* they are more forcing pieces than bishops in the sense that you cannot block knights; if your king is in check from a knight, either you have to move your king, or take the knight, which reduces the number of resources for the defending king; you can see this theme especially in the games of the great champion Mikhail Tal;
* their unusual movement generally offers more room for creativity; it often helps in creating unusual and visually spectacular attacks (again, see Tal's games---I am no expert, but he sacrificed knights maybe more often than any other piece);
* white knights on the 6th rank (or black ones on the 3rd) are incredibly powerful; I assume you saw the 16th game of the 1985 WCC (Kasparov himself explains this game in his documentary---there is a portion of it on Youtube); while mere mortals can only dream of ever playing such a beautiful game, this is still good to have in mind as a potential threat; the mentioned situation appears after Black's 16th move; there the knight cuts off all of White's heavy pieces (such knight is popularly called an "octopus knight");

```

[FEN ""]
[Event "Wch Moscow i 40/202; YB 4/91"]
[Site "16"]
[Date "1985.10.15"]
[EventDate "?"]
[Round "16"]
[Result "0-1"]
[White "Anatoly Karpov"]
[Black "Garry Kasparov"]
[ECO "B44"]
[WhiteElo "?"]
[BlackElo "?"]
[PlyCount "80"]

1.e4 c5 2.Nf3 e6 3.d4 cxd4 4.Nxd4 Nc6 5.Nb5 d6 6.c4 Nf6 7.N1c3
a6 8.Na3 d5 9.cxd5 exd5 10.exd5 Nb4 11.Be2 Bc5 12.O-O O-O
13.Bf3 Bf5 14.Bg5 Re8 15.Qd2 b5 16.Rad1 Nd3 17.Nab1 h6 18.Bh4
b4 19.Na4 Bd6 20.Bg3 Rc8 21.b3 g5 22.Bxd6 Qxd6 23.g3 Nd7
24.Bg2 Qf6 25.a3 a5 26.axb4 axb4 27.Qa2 Bg6 28.d6 g4 29.Qd2
Kg7 30.f3 Qxd6 31.fxg4 Qd4+ 32.Kh1 Nf6 33.Rf4 Ne4 34.Qxd3 Nf2+
35.Rxf2 Bxd3 36.Rfd2 Qe3 37.Rxd3 Rc1 38.Nb2 Qf2 39.Nd2 Rxd1+
40.Nxd1 Re1+ 0-1

```
* from White's point of view, getting a knight on f5 is a pretty good accomplishment; this is a good square because the knight is difficult to evict without creating serious weaknesses, and it is ready to sacrifice itself at any moment, so your opponent has to worry about it constantly (a good lecture about this can be found at the YouTube channel of Chess Club and Scholastic Center of Saint Louis)

**What I do not like about knights**:
* I guess they are in general worse pieces than bishops; they are more difficult to manoeuvre, as they are slower than bishops, they also get stuck more easily than bishops (there are no "bishop on a rim..." sayings in chess)
* pinning a knight is usually easier than pinning a bishop, and one has to look after knight pins, especially in certain openings, so you have to be more careful with knights, than with bishops in that respect.

That's it for now. I hope it will help. I just listed things as they came to my mind. It's neither meant to be comprehensive, not objectively correct. It's a list of subjective views. The question itself is quite general, so it's hard to give a concrete and objective answer.

But I do want to say that while it is good to have basic guidelines in chess for bishops, knights, and everything else, it is also important to think about them and try to evaluate them for yourself before accepting (or rejecting) them. Good luck!
> 4 votes

# Answer
There are many good positional books that cover this topic in depth, such as Silman's "Reassess Your Chess." For a lighter answer, there are several good guidelines (many of which are well-known):

**Middlegame guidelines**

* Is the position open or closed?
    + Open positions favor bishops; closed positions favor knights.
* Does the knight have advanced outposts on which it can do something?
    + Powerful knights that cannot be driven away are valuable.
* Does the bishop have an active function?
    + Bad bishops (blocked by own pawns) and ghost bishops (the battle is being fought on the opposite color) can be useless.
* Does one side have the bishop-pair?
    + GM Larry Kaufman, with the aid of non-subjective silicon, says the bishop-pair is worth 1/2 pawn. However, if the position is closed, this 1/2 pawn can be more than offset by the ineffectiveness of bishops in the position.
* Is there a weak square complex, especially around the king?
    + If so, a bishop of that color is more valuable for both sides, unless the bishop is trapped.
* Bishops of opposite colors favors the attacker in the middlegame.

**Endgame guidelines**

* Are all pawns on one side, or are there pawns on both flanks?
    + One side favors knight due to its ability to cover both colors
    + Both flanks favors bishop due to its long-distance range
* Is there a rook-pawn?
    + Rook-pawn + bishop of wrong color is a draw if the opposing king is well placed.
    + Rook-pawn + knight is a win even if the opposing king is well placed, unless the pawn is (or is forced to go to) the 7th rank.
* Are there no pawns?
    + 2 bishops mate is easy, bishop + knight mate is hard, and 2 knights mate cannot be forced
* Is one side up in pawns?
    + Bishops of opposite colors tends to be drawish when there are no other pieces (excl. pawns).
* The endgame tends to be open, so keep that in mind.

The article by GM Larry Kaufman also somewhat addresses this topic.

Note that bishop pairs are not redundant, and knight "pairs" are, so the bishop pair is better than 2 knights.

Mobility is important for bishops (beware of ghost bishops). Knights, if they are well placed and invulnerable, bypass the mobility consideration because the very purpose of mobility is activity, and well placed knights do not need to be mobile in order to be active (think knight blockade, or an attacking outposted knight).
> 4 votes

# Answer
In the endgame a Knight is usually better than a bishop. Two bishops are almost always better than a bishop and a knight.

However, you need to play at Master level for this to become important. There are many more factors more important in the position, including material. If you have a good bishop against a bad knight but you are the Queen down, it is not going to help you.
> 2 votes

# Answer
Is a Knight inferior to a Bishop? A perfect reply is, I think an impossibility.

Well the superiority of Knight over Bishop (or vice versa) is position dependent. I believe as a general guideline (but not a rule) that a Knight is only slightly superior to a Bishop, though several exceptions can be demonstrated.

Some people believe that a Knight is inferior to a Bishop in endings. It is worth noting that in about 55% of masters' games (single Bishop vs. single Knight) the Knight dominates the opposing Bishop. It is again often the case that Queen + Knight combination is better than a Queen + Bishop combination because the Knight is unique in its movement and thus supplements its friendly Queen. So is a R + N combination a little superior to a R + B team.

Some also believe that a Knight is pretty useless on an empty board, which can be a wrong notion. What finally becomes important is whether the piece (the Knight or the Bishop) watches crucial squares and does the 'job' well.

What about pairs of pieces? A Bishop pair is usually much worth compared to a Knight pair! The Bishop pair can win 80% or so of chess endings when they confront pair of Knights. What I like about chess is that it 'disproves' Mathematics in this context!
> 2 votes

# Answer
In endgames, especially when knight or bishop is against pawns, the knight has another advantage. It is that knights can reach and attack pawns on dark squares as well as light squares. Also for many players it is harder in the endgame to see knight moves than bishop moves.
> 1 votes

# Answer
No one has answered about engines yet, so I'll write about Stockfish, the strongest engine in the world at this moment with NNUE. It has gone through a lot of tweaking through fishtest which includes the relative piece values. These values actually change from middlegame to endgame as pawns become substantially more valuable.

https://github.com/official-stockfish/Stockfish/blob/9f6bcb38c032a18c8b1aec318d5c7255827f9c7b/src/types.h#L189

```
  PawnValueMg   = 126,   PawnValueEg   = 208,
  KnightValueMg = 781,   KnightValueEg = 854,
  BishopValueMg = 825,   BishopValueEg = 915,
  RookValueMg   = 1276,  RookValueEg   = 1380,
  QueenValueMg  = 2538,  QueenValueEg  = 2682,

```

Using these values at face value, Stockfish considers bishops to be slightly better than knights. However, note that these values are only one in a whole bunch and Stockfish searches much deeper than a human can.

Some interesting discussion https://www.reddit.com/r/chess/comments/e57lqz/stockfish\_doesnt\_use\_the\_traditional\_piece\_values/

Comment from Stockfish dev: https://www.reddit.com/r/chess/comments/e57lqz/stockfish\_doesnt\_use\_the\_traditional\_piece\_values/f9idquq/ (here is the referenced PSQT)

> This is not really correct. https://github.com/official-stockfish/Stockfish/blob/master/src/types.h#L182 As you can see there in middlegame values are even more off (like bishop is worth 6.5 pawns, etc). I think this is needed for stockfish to understand positional pawn sacs in midgame/opening. Pawns become more valuable into endgame, but still bishop is worth like 4.5 pawns. But you should understand smth :
>
> 1. stockfish eval is actually worse than human eval. It's needed to guide search. It thinks completely differently from how human do it that's why not all human concepts are good for sf eval and vice versa;
> 2. eval isn't pure piece values at all. For example, each piece is assigned bonuses with PSQT and everything but pawns and king is used in calculation of mobility. This bonuses are actually not 0-centered, so it can be somewhat compensating;
> 3. for human players it's much harder to win smth like B + R + P vs R + 4p than it is for stockfish, so for human players bigger material eval of pawn is more logical;
> 4. stockfish has a lot of bonuses for passers, so it's kinda balanced around it. This means that if pawn becomes a passer it becomes worth a ton so probably low material value of pawn is a subproduct of this.

Further statistics of analysis of games are at chess programming wiki https://www.chessprogramming.org/Bishop\_versus\_Knight which also brings up that a bishop pair is stronger than a knight and a bishop or two knights
> 0 votes

---
Tags: analysis, learning, engines, statistics, evaluation
---


title: Who decides to name an opening?

text:
# Question
Title: Who decides to name an opening?
Some openings are named after the players who spent their whole career playing a particular type of opening. For eg. Alekhine for Alekhine Defense, Philidor for Philidor Defense, William Evans for Evans Gambit. While some are named after the places they were played like French Defense, Dutch Defense, etc. So, my question is, who decides that a particular opening will be called a certain name? Is it **FIDE**, **World Chess**, or another organization?

# Answer
> 4 votes
> who decides that a particular opening will be called such and such?

The simple answer is "Chess players".

Wittgenstein's principle of "The meaning is the use" also applies to chess. If more chess players over time call a particular opening "A" rather than "B" then it becomes "A".

> Is it FIDE?

No. FIDE actually tried back in the early 1930's but failed miserably. Their one success was in changing the Greco Counter Gambit to the Latvian Gambit. Chess historian, Edward Winter, wrote about this here.

> The delegates from Czechoslovakia agreed to draw up a draft by 1 April 1930. At that year’s FIDE Congress, in Hamburg, a committee was set up (involving the federations of Czechoslovakia, Germany, Holland, Poland and Sweden) to prepare by the following year a report on the draft (source: FIDE minutes of the 1930 Congress, page 18). In the summer of 1931 FIDE met in Prague and, as noted on page 7 of the minutes, the Secretary of the Czechoslovakian Federation, Josef Louma, reported that the draft had been revised by a large number of chess figures, including Tartakower and Grünfeld. Another year went by. Page 9 of the minutes of the Paris, 1932 Congress contained a brief note by the FIDE President, Alexander Rueb, that no further news was available on the openings project (which was described as ‘important mais difficile et considérable’. But then at Folkestone in 1933 the delegate from Czechoslovakia, Jan Bedrníček, presented a document by Louma, still described as a draft (‘avant-projet’). Rueb extended his warm congratulations, and the minutes (page 4) also reported that the work would be published, at FIDE’s expense, with profits going into the FIDE coffers. A further year passed, and it was not until the Zurich Congress in 1934 that, as noted on page 5 of the minutes, FIDE was able to announce with great pleasure that the book had just appeared

Winter goes on to give some examples of their chosen names:

> * 1 b4: ‘Partie Hunter-Englisch’
> * 1 d4 d5 2 Nd2: ‘Partie Breyer’
> * 1 d4 Nf6 2 c4 g6 3 ~ Bg7: ‘Défense Dr Euwe de la Partie indienne’
> * 1 e4 c5 2 Nf3 Nf6: ‘Défense Kljatzkine de la Partie sicilienne’
> * 1 e4 e6 2 d4 d5 2 Nc3 Bb4: ‘Défense Maroczy-Nimzowitch de la Partie française’
> * 1 e4 e5 2 Bc4: ‘Partie Spielmann’
> * 1 e4 f5: ‘Gambit en second’
> * 1 Nf3 d5 2 e4: ‘Gambit de Léopol’.

In those days French was the official language of FIDE although I don't think that was the reason they failed so utterly.

# Answer
> 1 votes
You could argue the openings listed in the Encyclopedia of Chess Openings (ECO), however they were chosen by the editors, are the standard reference for opening names, which seem to be pretty widely adopted in opening explorers (lichess, chess.com, see What are the letters and numbers next to an opening's name on online services?) and chess publications (chess programming wiki claims it is a de facto standard: https://www.chessprogramming.org/ECO).

---
Tags: opening, fide
---


# Question
Title: What is White's compensation in the Smith-Morra Gambit, Paulsen Formation (a6, e6, Nc6) after an early ...Na5?
The variation is almost forced if White aims for the standard Smith-Morra setup. At the end White is a pawn down and no longer has two bishops, but is well developed. However Black's setup does not seem to have any weaknesses that can be pressured by White's superior pieces.

White's most immediate plan is to strike on the flank with a4, provoking ...b4.

In most of games at 2000+ level, White ends up defending a worse endgame.

```
 [fen ""]
 1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 e6
 5. Nf3 Nc6 6. Bc4 a6 7. O-O b5 8. Bb3 Na5
 9. Re1 Nxb3 10. Qxb3

```

If Black reveals his intention to play ...a6 early, White has alternative plans: Play Bf4, threatening Nd5 with pressure on the dark squares c7, d6 and b6, leading to decent games with White retaining the initiative. So Black should delay ...a6 as much as he can, as Bf4 only makes sense after ...a6.

```
[fen ""]
1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 Nc6
5. Nf3 a6 6. Bf4 e6 7. Be2

```

Also, ...Na5 needs to be played immediately, as 8...Bb7 allows 9. a4 with initiative and nasty tricks from White. Example game:

```
[fen ""]
[White "Vivante-Sowter, John (2259)"]
[Black "Kavc, Andrej (2270)"]

1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 e6 5. Nf3 a6 { B21 Sicilian Defense: Smith-Morra Gambit Accepted, Kan Formation } 6. Bc4 b5 7. Bb3 Bb7 8. O-O Nc6 9. a4 b4 10. Nd5 Na5 11. Bg5 f6 12. Ne5 Bxd5 13. exd5 Nxb3 14. dxe6 dxe6 15. Qxb3 Qd5 16. Nc4 fxg5 17. Rad1 Qf5 18. Rfe1 Bc5 19. Nd6+ Bxd6 20. Rxd6 Nf6 21. Rdxe6+ Kf8 22. Qxb4+ Kf7 23. Qc4 Kg6 24. g4 Qf3 25. R1e3 Qd1+ 26. Kg2 Rad8 27. Rxf6+ gxf6 28. Qe4+ Kf7 { The game is a draw. } 1/2-1/2

```

# Answer
> 1 votes
```
[Event "Morra Gambit Accepted - Paulsen Formation"]
[FEN "RNBQKBNR/PPPPPPPP/8/8/8/8/pppppppp/rnbqkbnr b KQkq - 1"]
[StartPly "14"]

1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 e6 5.Nf3 Nc6 6.Bc4 a6 7.O-O b5

```

To investigate the position after 7...b5, I setup a round-robin tournament between **Stockfish NNUE** 14.1, **Stockfish Classical** 14.1, **Komodo Dragon** 2.6.1, and **Leela Chess Zero** (Lc0) 28.2. These 4 engines are arguably the top chess-playing entities on the planet at the moment.

Each engine played W and B against every other engine. The time control was 10/10 and each engine was given 16 logical cores (3080 Ti for Lc0) with 8 GB of RAM.

Based on the results:

* All 12 games were drawn. This is strong evidence for the theory that White has sufficient compensation for the pawn.
* In every game every engine evaluation stayed between +1/-1 pawn. So no dramatic surprises, and more evidence that White has sufficient compensation.
* Most games were fought with a material imbalance as part of complex unbalanced positions.
* Most games were very tactical in nature - so fully fitting the typical Morra Gambit theme.
* Every engine played 8. Bd3, not 8. Bb3.
* Several games ended with a Black fortress - Black down material, but creating an impenetrable barrier to the White queen.
* Several games included a White sac on b5.
* As Black, Dragon always insisted on returning the pawn by allowing a4, axb5, and Bxb5.

# Answer
> 1 votes
To be honest, I see very little there, but Re1 also just looks like it is not in the spirit of the opening since it does little to add any pressure to the center. Of course, if black were to play d5, then it would make sense, but black will probably refrain from playing that for quite a while. Bc2 probably should be played there, and follow it up with the standard Qe2 and Rd1.

Overall, the only compensating factors right now are a slight lead in development, and more space; but as always, in such positions, if the other side is very solid, they can catch up in development, and then the extra pawn will become a major factor.

There is a reason the Morra is only popular at lower levels: It just loses a pawn, and there are not many redeeming factors.

---
Tags: opening, analysis, sicilian-defense, smith-morra-gambit
---


# Question
Title: Is there a record for threefold repetition for when the claimed positions are the farthest apart, in terms of moves?
That’s one long question, so let’s break it down. Threefold repetition, as many know, is when a draw occurs, after the same position, with all piece types on the same square, all possible moves and rights are the same, happens three times in a game of chess. The draw can be claimed whether or not the positions are consecutive or not.

My question is based on the non-consecutive part. Is there any sort of or record for when a draw was claimed for threefold repetition, when the three congruent positions, are the farthest apart by number of moves?

Essentially, the “number of moves” means this: Somtime in the game, position one occurs. So and so many moves later, position two happens. Then the third and final position is reached at last.

One could view this in two ways: What is the greatest number of moves between positions one and three, OR, What is the greatest number of moves from position one to position two, and then from position two to position three?

The game must have ended on the basis of a threefold-repetition claim.

# Answer
> 5 votes
Here is an improvement over my original suggestion. The game finishes after White's 128th move, repeating the position after their 62nd and 87th moves, so the distance is 66 moves. The source for this game was Mark Crowther's The Week in Chess.

```
[FEN ""]
[Event "Int ch-Central SRB Op A"]
[Site "Paracin SRB"]
[Date "2016.07.12"]
[Round "7.38"]
[White "Tisma,I"]
[Black "Krasteva,Beloslava"]
[Result "1/2-1/2"]

1. Nf3 d5 2. d4 Nf6 3. c4 e6 4. g3 Be7 5. Bg2 O-O 6. O-O Nbd7 7. Qc2 c5 8.
cxd5 exd5 9. dxc5 Nxc5 10. Nc3 Be6 11. Be3 Rc8 12. Rfd1 Nce4 13. Qa4 Nxc3
14. bxc3 a6 15. Rab1 Bd7 16. Qb3 b5 17. Ne5 Be6 18. Bd4 Qc7 19. a4 Rb8 20.
axb5 Rxb5 21. Qa2 Rfb8 22. Rxb5 axb5 23. Nd3 Ne4 24. Qb2 Bf6 25. Bxe4 dxe4
26. Nb4 Rd8 27. Nc2 Bc4 28. Ne3 Bg5 29. Ng2 Ra8 30. Ra1 Qb7 31. h4 Be7 32.
Rxa8+ Qxa8 33. Ne3 Qa4 34. Qd2 Be6 35. Kh2 h6 36. Ng2 Qa8 37. Qf4 Bc4 38.
Qg4 Bf8 39. Nf4 Qc6 40. h5 Be6 41. Nxe6 Qxe6 42. Qxe6 fxe6 43. Be5 Kf7 44.
Kh3 Bc5 45. e3 Be7 46. Kg4 Bg5 47. Bd4 Kf8 48. f4 Bf6 49. Bxf6 gxf6 50. f5
e5 51. Kh3 Ke7 52. Kg2 Kd6 53. Kf2 Kc5 54. Ke2 b4 55. g4 bxc3 56. Kd1 Kd6
57. Kc2 Kc6 58. Kxc3 Kc5 59. Kb3 Kd5 60. Kb4 Kd6 61. Kb5 Kd5 62. Ka4 Kc6
63. Kb3 Kd7 64. Kc3 Kc7 65. Kb4 Kd6 66. Kb5 Kd5 67. Kb6 Kd6 68. Kb7 Kd7 69.
Ka6 Kc6 70. Ka5 Kc5 71. Ka4 Kc6 72. Kb3 Kd7 73. Kc3 Kc7 74. Kc4 Kc6 75. Kb3
Kd7 76. Kb4 Kd6 77. Kb5 Kd5 78. Ka6 Kc6 79. Ka7 Kc7 80. Ka8 Kc8 81. Ka7 Kc7
82. Ka6 Kc6 83. Ka5 Kc5 84. Ka4 Kc6 85. Ka3 Kc5 86. Kb3 Kd5 87. Ka4 Kc6 88.
Kb4 Kd6 89. Kb5 Kd5 90. Kb6 Kd6 91. Ka5 Kc5 92. Ka4 Kc6 93. Ka3 Kc7 94. Kb3
Kd7 95. Kb4 Kd6 96. Kb5 Kd5 97. Kb6 Kd6 98. Ka5 Kc5 99. Ka4 Kc6 100. Ka3
Kc7 101. Kb2 Kd8 102. Kc3 Kc7 103. Kb3 Kd7 104. Kc3 Kc7 105. Kb4 Kd6 106.
Ka5 Kc5 107. Ka4 Kc6 108. Kb3 Kd7 109. Kc3 Kc7 110. Kb4 Kd6 111. Kb5 Kd7
112. Kb6 Kd6 113. Kb7 Kd7 114. Ka6 Kc6 115. Ka5 Kc5 116. Ka4 Kc6 117. Ka3
Kc7 118. Kb3 Kd7 119. Kc3 Kc7 120. Kb3 Kd7 121. Ka4 Kc6 122. Kb4 Kd6 123.
Kb5 Kd5 124. Kb6 Kd6 125. Kb5 Kd5 126. Kb6 Kd6 127. Kb5 Kd5 128. Ka4
1/2-1/2

```

The following was my original offering which finishes after Black's 146th move, with the same position having previously occurred after their 96th and 117th moves.

```
[fen ""]
[Event "Internet Section 14-A"]
[Site "Dos Hermanas"]
[Date "2003.03.14"]
[Round "1"]
[White "Keskinen, Sauli"]
[Black "Verhagen, Emmanuel"]
[Result "1/2-1/2"]

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. c3 d3 5. Bxd3 d6 6. h3 Be7 7. O-O Nf6 8.
Nd4 O-O 9. Nd2 Bd7 10. f4 Qc8 11. N2f3 a6 12. Be3 Nxd4 13. cxd4 c5 14. Rc1
b5 15. b3 Qb7 16. dxc5 dxc5 17. Bxc5 Bxc5+ 18. Rxc5 Qb6 19. b4 a5 20. a3
axb4 21. axb4 Rfd8 22. Kh2 Be6 23. Qb1 h6 24. Rxb5 Qd6 25. Ne5 Nd7 26. Rd1
Nxe5 27. fxe5 Qe7 28. Rc5 Qg5 29. Qc1 Qg6 30. b5 Ra2 31. Bf1 Rxd1 32. Qxd1
Qxe4 33. Qd8+ Kh7 34. Bd3 Rxg2+ 35. Kh1 Bf5 36. Bxe4 Bxe4 37. Qd4 Rg4+ 38.
Kh2 Rg2+ 39. Kh1 Rg4+ 40. Kh2 Rg2+ 41. Kh1 Rg4+ 42. Qxe4+ Rxe4 43. Kg2 Rb4
44. Kg3 Kg6 45. Rd5 Kf5 46. Rd7 Kxe5 47. Rxf7 g5 48. Rh7 Rxb5 49. Rxh6 Kf5
50. Rh8 Rb3+ 51. Kh2 Kf4 52. Rf8+ Ke4 53. Kg2 Ke5 54. Rf2 Ke4 55. Rf8 Ke5
56. Re8+ Kf5 57. Rf8+ Kg6 58. Rg8+ Kh5 59. Rh8+ Kg6 60. Rf8 Kh5 61. Rf7 Kg6
62. Rf8 Kh5 63. Rc8 Kg6 64. Rc6+ Kh5 65. Rf6 g4 66. Rf5+ Kh4 67. hxg4 Kxg4
68. Rf8 Rb2+ 69. Kf1 Kg3 70. Ke1 Kg4 71. Rg8+ Kf3 72. Rf8+ Ke3 73. Re8+ Kf3
74. Rf8+ Ke3 75. Re8+ Kf3 76. Kd1 Rh2 77. Kc1 Rg2 78. Kd1 Rh2 79. Rf8+ Ke3
80. Re8+ Kd3 81. Rd8+ Ke3 82. Ra8 Kd3 83. Ra3+ Ke4 84. Ke1 Kf4 85. Kf1 Ke4
86. Kg1 Rb2 87. Ra4+ Kf3 88. Ra3+ Kf4 89. Ra8 Kf3 90. Rf8+ Kg3 91. Rg8+ Kf3
92. Rf8+ Kg3 93. Rg8+ Kf3 94. Ra8 Kg3 95. Ra3+ Kf4 96. Kf1 Ke4 97. Ke1 Kf4
98. Kd1 Rh2 99. Kc1 Ke4 100. Kb1 Kd4 101. Ra4+ Ke3 102. Ra8 Kd3 103. Rd8+
Kc3 104. Rd1 Kb3 105. Rd3+ Kc4 106. Rd8 Kc3 107. Rc8+ Kb3 108. Rb8+ Kc3
109. Rg8 Kb3 110. Rg3+ Kc4 111. Rg4+ Kb3 112. Rg3+ Kc4 113. Kc1 Kd4 114.
Kd1 Ke4 115. Ke1 Kf4 116. Ra3 Ke4 117. Kf1 Rb2 118. Ke1 Kd4 119. Ra4+ Ke3
120. Ra3+ Ke4 121. Kd1 Kd4 122. Kc1 Rh2 123. Ra8 Kc3 124. Rc8+ Kd3 125.
Rd8+ Ke3 126. Ra8 Kd3 127. Ra3+ Kc4 128. Ra4+ Kc3 129. Ra3+ Kc4 130. Ra8
Kc3 131. Rc8+ Kd3 132. Rd8+ Kc3 133. Rc8+ Kd3 134. Rd8+ Kc3 135. Rc8+ Kd3
136. Kb1 Kd4 137. Rd8+ Kc3 138. Rg8 Kb3 139. Rg3+ Kc4 140. Kc1 Kd4 141. Kd1
Ke4 142. Ke1 Kf4 143. Ra3 Ke4 144. Ra4+ Ke3 145. Ra3+ Ke4 146. Kf1 Rb2
1/2-1/2

```

I have some longer examples but, in those cases, the repetitions occur more than three times.

The original process was fairly messy but I have now streamlined it in the light of experience:

* Use my pgn-extract program to identify games with three-fold repetition.
* Use pgn-extract again to output the matched games in EPD notation - essentially, the FEN string after every move.
* Use a Perl script to read the EPD version of a game and find the distance between the first and last occurrences of the terminating position, and the number of repetitions.
* Sort the distances, find the largest and then match it up with the original game. As a side effect, this process allows those games that didn't actually end by repetition to be eliminated.

Of 3.2M games in one database, about 50,000 had 3-fold repetitions occurring somewhere but only around 35,000 ended by repetition. Of those, about 87% ended as soon as the third repetition occurred.

Here is an example with a longer distance: 73 moves occurring 10 times (48, 53, 61, etc.).

```
[FEN ""]
[Event "GER-chT U12"]
[Site "Verden/Aller"]
[Date "2002.12.30"]
[Round "7.2"]
[White "Mader, Manuela"]
[Black "Voelz, Michael"]
[Result "1/2-1/2"]

1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 Bxb4 5. c3 Be7 6. d4 exd4 7. O-O d3 8.
Qb3 d5 9. Bxd5 Na5 10. Bxf7+ Kf8 11. Qd5 Qxd5 12. Bxd5 c6 13. Bxg8 Rxg8 14.
Nbd2 c5 15. Nb3 Nc6 16. Ba3 c4 17. Bxe7+ Kxe7 18. Nbd4 Nxd4 19. Nxd4 Bd7
20. a4 b6 21. Rfb1 Rgb8 22. Rb4 Rc8 23. Kf1 Kd6 24. Ke1 Rc5 25. Kd2 Rf8 26.
Ke3 Ke5 27. a5 b5 28. Rab1 a6 29. Rf1 g5 30. Nf3+ Ke6 31. Nd4+ Ke5 32. Nf3+
Kd6 33. Nd4 Re5 34. Nf3 Rc5 35. Nd4 Bg4 36. f3 Bd7 37. h3 Re5 38. Rf2 Re7
39. Rb1 Ke5 40. Rh1 h6 41. g3 Ref7 42. Rhh2 h5 43. g4 h4 44. Rh1 Rf4 45.
Rhf1 Re8 46. Rg1 Rg8 47. Rgf1 Rd8 48. Rd1 Rb8 49. Rb1 Re8 50. Re1 Rb8 51.
Rb1 Ra8 52. Ra1 Rd8 53. Rd1 Rh8 54. Rh1 Rhf8 55. Rhf1 Rg8 56. Rg1 Rb8 57.
Rb1 Rc8 58. Rc1 Ra8 59. Ra1 Raf8 60. Raf1 Rd8 61. Rd1 Re8 62. Re1 Rc8 63.
Rc1 Rg8 64. Rb1 Rgf8 65. Rbf1 Rd8 66. Rd1 Rc8 67. Rc1 Rb8 68. Rb1 Rbf8 69.
Rbf1 Re8 70. Re1 Rb8 71. Rb1 Ra8 72. Ra1 Rg8 73. Rg1 Re8 74. Re1 Rd8 75.
Rd1 Rg8 76. Rg1 Rb8 77. Rb1 Rc8 78. Rc1 Rcf8 79. Rcf1 Rb8 80. Rb1 Ra8 81.
Ra1 Rg8 82. Rg1 Rgf8 83. Rgf1 Rd8 84. Rd1 Rc8 85. Rc1 Rb8 86. Rb1 Ra8 87.
Ra1 Rh8 88. Rh1 Rg8 89. Rg1 Rgf8 90. Rgf1 Rb8 91. Rb1 Ra8 92. Ra1 Raf8 93.
Raf1 Rb8 94. Rb1 Re8 95. Re1 Ref8 96. Ref1 Rd8 97. Rd1 Rb8 98. Rb1 Rbf8 99.
Rbf1 Re8 100. Re1 Rd8 101. Rd1 Rdf8 102. Rdf1 Rg8 103. Rg1 Rgf8 104. Rgf1
Rb8 105. Rb1 Rbf8 106. Rbf1 Re8 107. Re1 Rd8 108. Rd1 Rb8 109. Rb1 Ra8 110.
Ra1 Rh8 111. Rh1 Rhf8 112. Rhf1 Rc8 113. Rc1 Rb8 114. Rb1 Rg8 115. Rg1 Re8
116. Re1 Rc8 117. Rc1 Ra8 118. Ra1 Rh8 119. Rh1 Rhf8 120. Rhf1 Rd8 121. Rd1
1/2-1/2

```

I have no idea what was going on with the following example. The repetition occurs 28 times, starting after White's 67th move.

```
[FEN ""]
[Event "?"]
[Site "Dos Hermanas"]
[Date "2004.03.08"]
[Round "9"]
[White "Garvin Mejia, Ricardo Luis"]
[Black "Arroyo, Roberto Carlos"]
[Result "1/2-1/2"]

1. e4 d5 2. exd5 Qxd5 3. Nc3 Qa5 4. d4 Nf6 5. Bc4 Bf5 6. Ne2 e6 7. Ng3 Bg6
8. Bd2 c6 9. h4 h6 10. Nd5 Qd8 11. Nf4 Bh7 12. Qe2 Bxc2 13. Bc3 Bh7 14. d5
cxd5 15. Bxf6 gxf6 16. Nxd5 Be7 17. Nxe7 Qxe7 18. O-O O-O 19. Rfe1 Nc6 20.
Bb5 Nd4 21. Qg4+ Bg6 22. Qxd4 e5 23. Qg4 Kh8 24. Qe2 a6 25. Bd3 Rg8 26. Qe3
Kh7 27. Nf5 Bxf5 28. Bxf5+ Kg7 29. Rad1 Rad8 30. Rxd8 Qxd8 31. f4 exf4 32.
Qxf4 Qb6+ 33. Qf2 Qxf2+ 34. Kxf2 Rd8 35. Re2 Rd5 36. g4 Ra5 37. a3 Ra4 38.
Re7 b5 39. Ra7 a5 40. Be6 b4 41. Bxf7 Kf8 42. Bb3 bxa3 43. Bxa4 a2 44. Ra8+
Kg7 45. Ra7+ Kf8 46. Ra8+ Kg7 47. Ra7+ Kf8 48. Ra8+ Kg7 49. Ra7+ Kf8 50.
Ra8+ Kg7 51. Ra7+ Kf8 52. Ra8+ Kg7 53. Ra7+ Kf8 54. Ra8+ Kg7 55. Ra7+ Kf8
56. Ra8+ Kg7 57. Ra7+ Kf8 58. Ra8+ Kg7 59. Ra7+ Kf8 60. Ra8+ Kg7 61. Ra7+
Kf8 62. Ra8+ Kg7 63. Ra7+ Kf8 64. Ra8+ Kg7 65. Ra7+ Kf8 66. Rxa5 a1=Q 67.
Ra8+ Kg7 68. Ra7+ Kf8 69. Ra8+ Kg7 70. Ra7+ Kf8 71. Ra8+ Kg7 72. Ra7+ Kf8
73. Ra8+ Kg7 74. Ra7+ Kf8 75. Ra8+ Kg7 76. Ra7+ Kf8 77. Ra8+ Kg7 78. Ra7+
Kf8 79. Ra8+ Kg7 80. Ra7+ Kf8 81. Ra8+ Kg7 82. Ra7+ Kf8 83. Ra8+ Kg7 84.
Ra7+ Kf8 85. Ra8+ Kg7 86. Ra7+ Kf8 87. Ra8+ Kg7 88. Ra7+ Kf8 89. Ra8+ Kg7
90. Ra7+ Kf8 91. Ra8+ Kg7 92. Ra7+ Kf8 93. Ra8+ Kg7 94. Ra7+ Kf8 95. Ra8+
Kg7 96. Ra7+ Kf8 97. Ra8+ Kg7 98. Ra7+ Kf8 99. Ra8+ Kg7 100. Ra7+ Kf8 101.
Ra8+ Kg7 102. Ra7+ Kf8 103. Ra8+ Kg7 104. Ra7+ Kf8 105. Ra8+ Kg7 106. Ra7+
Kf8 107. Ra8+ Kg7 108. Ra7+ Kf8 109. Ra8+ Kg7 110. Ra7+ Kf8 111. Ra8+ Kg7
112. Ra7+ Kf8 113. Ra8+ Kg7 114. Ra7+ Kf8 115. Ra8+ Kg7 116. Ra7+ Kf8 117.
Ra8+ Kg7 118. Ra7+ Kf8 119. Ra8+ Kg7 120. Ra7+ Kf8 121. Ra8+ 1/2-1/2

```

For completeness, here is the 131-move repetition but from the tags I presume this was played in an Under-10 tournament, so probably not of great significance:

```
[FEN ""]
[Event "GER-ch U10"]
[Site "Ueberlingen"]
[Date "2000.06.05"]
[Round "3"]
[White "Ugur, Ozgur"]
[Black "Cammann, Tim"]
[Result "1/2-1/2"]

1. e4 e5 2. Nf3 Nc6 3. Bc4 Nf6 4. Nc3 Bb4 5. d3 Nd4 6. Be3 c5 7. O-O O-O 8.
a3 Bxc3 9. bxc3 Nxf3+ 10. Qxf3 d6 11. h3 Qa5 12. Qd1 Qxc3 13. Bd2 Qb2 14.
Ra2 Qb6 15. Qf3 Qd8 16. Qg3 Ne8 17. Bh6 Bd7 18. Be3 b5 19. Bb3 a5 20. c3 a4
21. Bc2 Qa5 22. Bd2 Rb8 23. Qe3 Be6 24. Rb2 Nf6 25. Rfb1 Bd7 26. c4 Qa6 27.
cxb5 Bxb5 28. Bc3 Rb7 29. Qd2 Rfb8 30. Qd1 h6 31. Bd2 d5 32. exd5 Nxd5 33.
Qg4 Bd7 34. Rxb7 Rxb7 35. Qd1 Rxb1 36. Qxb1 Qb5 37. Qe1 f6 38. Qe4 Qc6 39.
Bxa4 Qxa4 40. Qxd5+ Kh7 41. Qa2 Bb5 42. Be3 Qd1+ 43. Kh2 Qxd3 44. Bxc5 Qc4
45. Qxc4 Bxc4 46. Kg3 Kg8 47. Kg4 Kf7 48. Kh5 Be2+ 49. Kh4 g5+ 50. Kg3 h5
51. f3 f5 52. Be3 f4+ 53. Kf2 Bd3 54. Bd2 Kf6 55. Ke1 Kf5 56. Kf2 h4 57.
Ke1 e4 58. fxe4+ Bxe4 59. Kf2 g4 60. a4 g3+ 61. Kg1 Bd5 62. a5 Bc4 63. a6
Bxa6 64. Bxf4 Kxf4 65. Kh1 Bc8 66. Kg1 Bb7 67. Kh1 Bxg2+ 68. Kxg2 Ke3 69.
Kg1 Ke2 70. Kg2 Ke1 71. Kg1 Ke2 72. Kg2 Ke3 73. Kg1 Ke4 74. Kg2 Kf4 75. Kg1
Kf5 76. Kg2 Ke4 77. Kg1 Ke5 78. Kg2 Kf4 79. Kg1 Kf3 80. Kf1 Ke3 81. Kg1 Ke2
82. Kg2 Ke3 83. Kg1 Kf4 84. Kg2 Ke4 85. Kg1 Kd5 86. Kg2 Ke4 87. Kg1 Kd3 88.
Kh1 Kc3 89. Kg2 Kd2 90. Kh1 Kd3 91. Kg1 Kc4 92. Kg2 Kd5 93. Kh1 Ke6 94. Kg2
Kf7 95. Kf3 Kg6 96. Kg2 Kh5 97. Kf3 Kh6 98. Kg2 Kh7 99. Kg1 Kg8 100. Kh1
Kf8 101. Kg2 Ke8 102. Kg1 Kd8 103. Kh1 Kc8 104. Kg2 Kb8 105. Kg1 Ka8 106.
Kg2 Ka7 107. Kg1 Ka6 108. Kg2 Ka5 109. Kg1 Ka4 110. Kg2 Ka3 111. Kg1 Ka2
112. Kg2 Ka1 113. Kg1 Kb1 114. Kg2 Kc1 115. Kg1 Kb2 116. Kg2 Kb3 117. Kg1
Kb4 118. Kg2 Kb5 119. Kg1 Kb6 120. Kg2 Kb7 121. Kg1 Kb8 122. Kg2 Kc8 123.
Kg1 Kc7 124. Kf1 Kc6 125. Kg2 Kc5 126. Kg1 Kc4 127. Kg2 Kc3 128. Kg1 Kc2
129. Kg2 Kc1 130. Kg1 Kd1 131. Kh1 Kd2 132. Kg2 Kd3 133. Kh1 Kd4 134. Kg2
Kd5 135. Kg1 Kd6 136. Kg2 Kd7 137. Kg1 Kd8 138. Kg2 Ke8 139. Kg1 Ke7 140.
Kg2 Ke6 141. Kg1 Ke5 142. Kg2 Ke4 143. Kg1 Ke3 144. Kh1 Kf4 145. Kg2 Kg5
146. Kf3 Kh6 147. Kg2 Kh7 148. Kg1 Kg7 149. Kg2 Kf7 150. Kg1 Ke7 151. Kg2
Kd7 152. Kg1 Kc7 153. Kg2 Kb7 154. Kg1 Ka7 155. Kg2 Ka6 156. Kg1 Kb6 157.
Kg2 Kc6 158. Kg1 Kd6 159. Kg2 Ke6 160. Kg1 Kf6 161. Kg2 Kg6 162. Kg1 Kh5
163. Kg2 Kg5 164. Kg1 Kf5 165. Kg2 Ke5 166. Kg1 Kd5 167. Kg2 Kc5 168. Kg1
Kb5 169. Kg2 Ka5 170. Kg1 Ka4 171. Kg2 Ka3 172. Kg1 Ka2 173. Kg2 Kb2 174.
Kg1 Kc2 175. Kg2 Kd2 176. Kg1 Kd3 177. Kg2 Kd4 178. Kg1 Kd5 179. Kg2 Kd6
180. Kg1 Kd7 181. Kg2 Kd8 182. Kf1 Ke8 183. Kg1 Kf8 184. Kg2 Kg8 185. Kg1
Kh8 186. Kg2 Kh7 187. Kg1 Kh6 188. Kg2 Kh5 189. Kg1 Kg5 190. Kg2 Kf5 191.
Kg1 Ke5 192. Kg2 Kd5 193. Kg1 Kc6 194. Kg2 Kb5 195. Kg1 Kb4 196. Kg2 Kc4
197. Kg1 Kd3 198. Kg2 Ke4 199. Kg1 Ke5 200. Kg2 Kf6 201. Kf1 Kf7 202. Kg1
Kg7 203. Kg2 Kf6 204. Kg1 Ke7 205. Kg2 Kd7 206. Kf3 Kc6 207. Ke2 Kc5 208.
Kf1 Kc4 209. Kg2 Kb4 210. Kg1 Kb5 211. Kg2 Kc6 212. Kg1 Kd7 213. Kg2 Ke7
214. Kg1 Kd6 215. Kg2 Kc7 216. Kg1 Kb6 217. Kg2 Ka5 218. Kg1 Ka6 219. Kg2
Ka7 220. Kg1 Ka8 221. Kg2 Kb8 222. Kg1 Kc8 223. Kg2 Kd8 224. Kg1 Ke8 225.
Kg2 Kf8 226. Kg1 Kg8 227. Kg2 Kh7 228. Kg1 Kg6 229. Kg2 Kf5 230. Kg1 Ke6
231. Kg2 Kd6 232. Kg1 Kc7 233. Kg2 Kd8 234. Kg1 Ke7 235. Kg2 Kf7 236. Kg1
Ke6 237. Kg2 Kd5 238. Kg1 Kc4 239. Kg2 Kb3 240. Kg1 Kc4 241. Kg2 Kc3 242.
Kg1 Kb4 243. Kg2 Ka5 244. Kg1 Kb6 245. Kh1 Kc7 246. Kg1 Kd8 247. Kh1 Ke8
248. Kg1 Kd7 249. Kg2 Kc6 250. Kg1 Kb6 251. Kf1 Kc5 252. Kg2 Kd5 253. Kg1
Kd4 254. Kg2 Kd5 255. Kg1 Ke6 256. Kg2 Kf7 257. Kg1 Kf6 258. Kg2 Kf5 259.
Kg1 Ke5 260. Kg2 Kd5 261. Kg1 Kc4 262. Kf1 Kd5 263. Kg2 Kc6 264. Kg1 Kb5
265. Kg2 Kb4 266. Kg1 Kc5 267. Kg2 Kd6 268. Kg1 Ke5 269. Kg2 Kd5 270. Kg1
Kc4 271. Kg2 Kc3 272. Kg1 Kb3 273. Kg2 Kc4 274. Kg1 Kd3 275. Kh1 Ke4 276.
Kg2 Ke5 277. Kg1 Ke6 278. Kg2 Kf6 279. Kg1 Kg7 1/2-1/2

```

# Answer
> 2 votes
I would say 50 moves (possibly 49).

Three-fold repetition requires the game to return same position 3 times. This obviously can't happen if there are any captures or pawn moves, so therefore as long as the 3-fold repetition is possible so is the 50-move rule - which provides a hard upper limit.

# Answer
> 0 votes
I found this what is perhaps the strangest repetition ever in Tim Krabbe's Diary #26. I shall quote it in full for context.

"Last night on ICC, using my alias for the command obs * -c (which will get you to see the highest rated non-computer game), I chanced upon a 3 5 game between grandmasters Grandma (2938) and KingLoek (2929). After 39 moves, the position in the diagram was reached. There followed: 39...Rb5+ 40.Kc2 Rc5 41.Kb3 Rb5+ 42.Kc2 Rc5 43.Kb3 Rb5+ ICC does spot repetitions, but will only declare the game a draw if one of the players clicks 'draw'. Here, neither did. The game continued, watched by at least 60 people, including a few grandmasters:"

```
[FEN "8/p2R2pp/5k2/2rn1p2/2N5/PK3PP1/7P/8 b - - 0 1"]

1... Rb5+ 2. Kc2 Rc5 3. Kb3 Rb5+ 4. Kc2 Rc5 5. Kb3 Rb5+ 6. Kc2 Rc5 7. Kb3 Rb5+ 8. Kc2 Rc5 9. Kb3 Rb5+ 10. Kc2 Rc5 11. Kb3 Rb5+ 12. Kc2 Rc5 13. Kb3 Rb5+ 14. Kc2 Rc5 15. Kb3 Rb5+ 16. Kc2 Rc5 17. Kb3 Rb5+ 18. Kc2 Rc5 19. Kb3 Rb5+ 20. Kc2 Rc5 21. Kb3 Rb5+ 22. Kc2 Rc5 23. Kb3 Rb5+ 24. Kc2 Rc5 25. Kb3 Rb5+ 26. Kc2 Rc5 27. Kb3 Rb5+ 28. Kc2 Rc5 29. Kb3 Rb5+ 30. Kc2 Rc5 31. Kb3 Rb5+ 32. Kc2 Rc5 33. Kb3 Rb5+ 34. Kc2 Rc5 35. Kb3 Rb5+ 36. Kc2 Rc5 37. Kb3 Rb5+ 38. Kc2 Rc5 39. Kb3 Rb5+ 40. Kc2 Rc5 41. Kb3 Rb5+ 42. Kc2 Rc5 43. Kb3 Rb5+ 44. Kc2 Rc5 45. Kb3 Rb5+ 46. Kc2 Rc5 47. Kb3 Rb5+ 48. Kc2 Rc5 49. Kb3 Rb5+ 50. Kc2 Rc5 51. Kb3 Rb5+ 52. Kc2 Rc5 53. Kb3 Rb5+ 54. Kc2 Rc5 55. Kb3 Rb5+ 56. Kc2 Rc5 57. Kb3 Rb5+ 58. Kc2 Rc5 59. Kb3 Rb5+ 60. Kc2 Rc5 61. Kb3 Rb5+ 62. Kc2 Rc5 63. Kb3 Rb5+ 64. Kc2 Rc5 65. Kb3 Rb5+ 66. Kc2 Rc5 67. Kb3 Rb5+ 68. Kc2 Rc5 69. Kb3 Rb5+ 70. Kc2 Rc5 71. Kb3 Rb5+ 72. Kc2 Rc5 73. Kb3 Rb5+ 74. Kc2 Rc5 75. Kb3 Rb5+ 76. Kc2 Rc5 77. Kb3 Rb5+ 78. Kc2 Rc5 79. Kb3 Rb5+ 80. Kc2 Rc5 81. Kb3 Rb5+ 82. Kc2 Rc5 83. Kb3 Rb5+ 84. Kc2 Rc5 85. Kb3 Rb5+ 86. Kc2 Rc5 87. Kb3 Rb5+ 88. Kc2 Rc5 89. Kb3 Rb5+ 90. Kc2 Rc5 91. Kb3 Rb5+ 92. Kc2 Rc5 93. Kb3 Rb5+ 94. Kc2 Rc5 95. Kb3 Rb5+ 96. Kc2 Rc5 97. Kb3 Rb5+ 98. Kc2 Rc5 99. Kb3 Rb5+ 100. Kc2 Rc5 101. Kb3 Rb5+ 102. Kc2 Rc5 103. Kb3 Rb5+ 104. Kc2 Rc5 105. Kb3 Rb5+ 106. Kc2 Rc5 107. Kb3 Rb5+ 108. Kc2 Rc5 109. Kb3 Rb5+ 110. Kc2 Rc5 111. Kb3 Rb5+ 1/2-1/2

```

"44.Kc2 Rc5 45.Kb3 Rb5+ 46.Kc2 Rc5 47.Kb3 Rb5+ 48.Kc2 Rc5 49.Kb3 Rb5+ 50.Kc2 Rc5 51.Kb3 Rb5+ 52.Kc2 Rc5 53.Kb3 Rb5+ 54.Kc2 Rc5 55.Kb3 Rb5+ 56.Kc2 Rc5 57.Kb3 Rb5+ 58.Kc2 Rc5 59.Kb3 Rb5+ 60.Kc2 Rc5 61.Kb3 Rb5+ 62.Kc2 Rc5 63.Kb3 Rb5+ 64.Kc2 Rc5 65.Kb3 Rb5+ 66.Kc2 Rc5 67.Kb3 Rb5+ 68.Kc2 Rc5 69.Kb3 Rb5+ 70.Kc2 Rc5 71.Kb3 Rb5+ 72.Kc2 Rc5 73.Kb3 Rb5+ 74.Kc2 Rc5 75.Kb3 Rb5+ 76.Kc2 Rc5 77.Kb3 Rb5+ 78.Kc2 Rc5 79.Kb3 Rb5+ 80.Kc2 Rc5 81.Kb3 Rb5+ 82.Kc2 Rc5 83.Kb3 Rb5+ 84.Kc2 Rc5 85.Kb3 Rb5+ 86.Kc2 Rc5 87.Kb3 Rb5+ 88. Kc2 Rc5 89.Kb3 Rb5+ 90.Kc2 Rc5 91.Kb3 Rb5+ 92.Kc2 Rc5 93.Kb3 Rb5+ 94.Kc2 Rc5 95.Kb3 Rb5+ 96.Kc2 Rc5 97.Kb3 Rb5+ 98.Kc2 Rc5 99.Kb3 Rb5+ 100.Kc2 Rc5 101.Kb3 Rb5+ 102.Kc2 Rc5 103.Kb3 Rb5+ 104.Kc2 Rc5 105. Kb3 Rb5+ 106.Kc2 Rc5 107.Kb3 Rb5+ 108.Kc2 Rc5 109.Kb3 Rb5+ 110.Kc2 Rc5 111.Kb3 Rb5+ 112.Kc2 Rc5 113.Kb3 Rb5+ 114.Kc2 Rc5 115.Kb3 Rb5+ 116.Kc2 Rc5 117.Kb3 Rb5+ 118.Kc2 Rc5 119.Kb3 Rb5+ 120.Kc2 Rc5 121. Kb3 Rb5+ 122.Kc2 Rc5 123.Kb3 Rb5+ 124.Kc2 Rc5 125.Kb3 Rb5+ 126.Kc2 Rc5 127.Kb3 Rb5+ 128.Kc2 Rc5 129.Kb3 Rb5+ 130.Kc2 Rc5 131.Kb3 Rb5+ 132.Kc2 Rc5 133.Kb3 Rb5+ 134.Kc2 Rc5 135.Kb3 Rb5+ 136.Kc2 Rc5 137. Kb3 Rb5+ 138.Kc2 Rc5 139.Kb3 Rb5+ 140.Kc2 Rc5 141.Kb3 Rb5+ 142.Kc2 Rc5 143.Kb3 Rb5+ 144.Kc2 Rc5 145.Kb3 Rb5+ 146.Kc2 Rc5 147.Kb3 Rb5+ 148.Kc2 Rc5 149.Kb3 Rb5+ and here the text appeared: 'Game drawn by repetition 1/2-1/2'"

# Answer
> 0 votes
The answer is that the theoretical maximum is 75 moves. This is based on the Article 9.6.2 of the FIDE Laws of Chess, which defines "The game is drawn if any series of at least 75 moves have been made by each player without the movement of any pawn and without any capture."

This is perhaps best explained with an example. Suppose the second occurrence of the position happens 50 moves after the first occurrence, and the third occurrence happens 26 moves after the second occurrence. This means that the player will claim a draw 76 moves after the first occurrence, and the arbiter will evaluate and declare a draw already in the previous move by the 75 moves rule. The 76.th. move is in effect not a part of the game, because it already ended with a draw. This would only happen if the arbiter was not already attentive to declare the draw on the previous move, which can happen because arbiters have many duties during a tournament, and will not always check each game for this rule.

---
Tags: draw, threefold-repetition, records
---


# Question
Title: Puzzle: Forced game end in at most two halfmoves
Compose a position where

1. It's White to move
2. White can deliver checkmate or stalemate in 1 move
3. Or if they make a different move, then Black can deliver checkmate or stalemate in one 1 move

I needed 6 white pieces and 11 black pieces. Beat me!

Toned down example for understanding:

```
[FEN "7k/7P/7K/6BP/8/8/8/8 w - - 0 0"]

```

After the next White move, Black is either mated or stalemated, depending on if White plays Bf6 or not. (This does not meet the 3rd requirement).

# Answer
Just one piece fewer, but how about:

```
[FEN "5brr/4p1pq/4P1pk/4N1p1/6P1/6PK/6PP/8 w - - 0 1"]

1.Nd7= {Black stalemated} (1.Nf7#) (1.Nxg6 Kxg6#) (1.Nxg6 Qxg6= {White stalemated})

```
> 2 votes

# Answer
I knew it! 13 pieces:

```
[FEN "8/6p1/6P1/6PB/6P1/4p1pQ/4Pp1p/5K1k w - - 0 0"]

```

1.Qg2#/1.Qxg3=/1.Qh4 g2#/1.Qxh2+ K,gxh2=

Note that 5 pieces just stand around against 1.Qg4, which also ends the game, but in 1.5 moves - *still* too bad!
> 2 votes

---
Tags: problems, checkmate, stalemate
---


# Question
Title: How do you calculate the chess rating of players using the Ingo system?
I have been reading on the references below but could not understand it.

References:

**Edit**
After some further research I got other info on top players with Ingo rating.

# Answer
According to https://second.wiki/wiki/ingo-zahl

In Ingo, lower rating numbers indicate stronger players.

Take your "performance score" as the average result, as a percentage from 0 to 100. e.g., if you got 6.5 pts out of 10 games, this would be 65. Let's call this S.

Take the average rating of all the opponents and call this R.

With R and S, calculate the adjustment factor for your rating as R - (S-50) = R - S + 50.

Then calculate your new rating (I') from your old rating (I) as:

I' = ( (R-S+50) * n + I * E ) / (n+E)

Where n is the number of games played and E is a "development factor" which was based on the player's age:

| age | E |
| --- | --- |
| 0-19 | 10 |
| 20-24 | 15 |
| 25+ | 20 |
> 2 votes

# Answer
It is hard to get your head round because lower Ingo ratings are better than high ones (opposite of modern Elo based systems) and because none of the references above give numbers. So, what would Magnus Carlsen's Ingo rating be? What would my Ingo rating be? What about an "average" player? What about a beginner?

The Wikipedia reference gives some details of how the calculations work but misses out key details that still leave a feeling of incomprehension:

> New players receive a high, fixed starting score. Players' new ratings centre on the average rating of entrants to their competition: then if having achieved better than a net draw set of result, minus the number of percentage points it is over 50% (e.g. a 12–4 or 24–8 wins-to-losses result is, as ever, noted as a 75% tournament outcome) – if having achieved worse than this then the number, again in percent, is added to the average of the tournament entrants' scores; thus in all cases recalibrating all players after each tournament completely. A consequence is at most 50 points gained or shed per tournament (namely by a totally winning or totally losing participant) away from the tournament average.

This begs a number of questions.
What is the "high, fixed starting score" given to new players?
Does a round robin tournament with say 4 players really have the same weighting as a round robin with say 10 players? Seems unfair if true.

I found a number of references which clear up some of these questions.

First, this chess.com reference gives a formula for converting between Ingo and FIDE and also notes that Ingo ratings typically vary between 0 (strong, world champion) and 300 (complete beginner):

FIDE = 2840 - (INGO x 8) and
INGO = (2840 - FIDE) / 8

That would put Carlsen round about 0, an average 1500 FIDE player would be about 170 and a player who just gets a 1000 FIDE rating would be about 230.

The Ingo rating system may no longer be used for classical chess ratings but it is used for the Chinese variant, Xiangqi, at least by the European Xiangqi federation. I found this useful reference for its use in Xiangqi which gives more details.

> **1. Principles**: a) The "better" player the lower rating.
> INGO range is from about 10 (world champion) up to 250 (beginner), maximum rating should be 300.
> b) Rating performance has to be calculated strictly in chronological order of the tournaments.
> c) The ratings will be updated after each tournament.
> d) Each INGO rating gets an index that means the number of tournaments that have been calculated for this player.
> Example: a rating of 120-10 means an INGO of 120, resulting out of 10 rated tournaments.
>
> **2. Meanings**: One point difference means one percent more or less of expectancy range.
> Example: If A has a rating of 110 and the average of A's opponents is also 110, the expectancy range is exactly 50%; if the opponents' average is 100, expectancy range is 10% less than 50%, means 40% (when playing 10 games A should gain 4 points otherwise his INGO rating has to be changed).
>
> **3. Limits**: Due to the linearity of the INGO system, the calculating of expectancy ranges is limited to 50 points difference. (Of course it is not possible that a player may gain more than one point resp. less than 0 points per game..) So we have to cut off in case of opponents' rating differs more than 50 points from yours, when calculating your opponents' average.
> Example: A's INGO is 100, his opponents' 100,170,40, for calculation of average take 100,150,50, so the average will be 100 and A should gain 50% that means 1.5 points of the three games (three points in "Chinese" counting style).
>
> **4. Performance**: Row "H" shows the rating performance of a player for the calculated tournament.
>
> **5. New INGO**: Abbreviation of INGO is "F" (F-old, F-new).
> F is normally calculated as follows:
> F-new = (F-old * k + H) / (k + 1), where k means the expansion coefficient:
>
> **6. Coefficient**: The lower coefficient, the faster the changes!
> Normally the expansion coefficient is
> k = 3; if your index is less than 10, make:
> k = k - 1; if your index is less than 5, make:
> k = k - 1; for every game less than 5 in the current tournament, make:
> k = k + 1; if the tournament's time schedule is less than 1 hour per player (quickplay), k will be doubled:
> k = k + k but see 7.a Restrictions)
> Example: your rating is 120-4 and you play 3 games in your 5th tournament, your coefficient is:
> k = 3 (starting value)
> -1 (because less than 10 tournaments)
> -1 (because less than 5 tournaments)
> +2 (2 games less than 5)
> = 3!
> If this tournament is a quickplay tournament, k will now be doubled to 6!

It looks to me like this Xiangqi variant of the Ingo rating system has been updated to modern requirements (quickplay, handling weaker and stronger players with "k" factor, etc.) but it makes how it works much clearer than the Wikipedia article.
> 2 votes

---
Tags: rating
---


# Question
Title: Coming up with a plan at beginning of middlegame
I very often encounter the situation that I don't know how to come up with a plan after the opening. See this position, playing as Black, black to move:

```
[FEN "r3r1k1/1pp1qpp1/pb1p1n1p/4p3/1P2P3/2PP2BP/1P1Q1PP1/R2N1RK1 b - - 0 17"]

```

From my understanding, both Black's minor pieces are better than White's. The bishop has a great open diagonal and the knight is better placed, closer to the center. What I don't know is how to continue from here. ...d5 with support from the queen, knight, rook or the c pawn seems "natural" and it's even recommended by the engine, but what for? That weakens the e pawn which is already targeted by White's bishop.

Like I said, Black's bishop seems fine, and about the knight, with the current pawn structure I don't see an obvious better place for it.

# Answer
I will try to give an approach to assessing this position. My aim is not to reach a conclusion but to illustrate a process. It is a typical error to try and assess a position by looking at where the pieces and pawns currently stand, instead of asking where they can go to. OP does somewhat acknowledge this by saying "about the knight, *with the current pawn structure* I don't see an obvious better place for it." Well, how about f4? We get off to an immediate start with ..Nh5, threatening to win a piece. If then Bh2, then ....g5 (the pawn structure is not permanent) the Knight is going to f4 and if it is exchanged off we retake with the g-Pawn which will give us an open file for attack that outweighs the doubled Pawns. Oh, but there is a downside to ..g5. White will play Ne3 (that Knight was not so badly placed- I feel sure it went to d1 with this in mind!) and now White too will have a well placed Knight unless Black trades off that beautiful Bishop. If he does so, then if White is afraid of doubled pawns he will recapture with the Queen, but much better would be to retake with the Pawn, kicking the knight from its outpost. So we decide to keep our Bishop. and we have the line of play ..Nh5, Bh2 g5, Ne3 Nf4, Nf5 and now where does the Queen go?? Both e6 and f6 would protect the h-pawn, but e6 has the extra merit of combining nicely with a ..g4 push.

At this point I find myself liking ..Nh5 but suddenly notice that instead of Ne3 White might try g3, which is so ugly that it does not easily come to mind, but does defeat Blacks aims. If the Black Rook had been on f8 I could keep up the momentum with ..f5 So then I start to consider playing ..Rf8 at some stage, or even playing (in the position after ..Nh5, Bh2 g4, g3 f5 as a temporary sacrifice. But after Ne3 I find myself unable to do better than to get that Pawn back with ..Bxe3. My assessment now is that both positions have been damaged, and perhaps more so for Black.

So that did not work well, but I was trying, as I said, to illustrate a process. The engine recommendation of ..d5 does not seriously weaken the e-pawn. In fact after ..d5, exd Nxd5, it is the WPd3 that starts to look vulnerable. If White protects the e-pawn with, say, Qc2 then Black can play..Rad8 followed by doubling on the d-file. The move ..d5 is probably what should be played.

I will try to outline a procedure that might be followed, beginning with these questions.

1. Is the position stable? In particular is the Pawn structure stable? Which pieces are likely to still be on their present squares in five moves time? In ten moves time?
2. If a piece is likely to move, do I want to exchange it off? If not, what square would I like it to be on? What useful Pawn moves do I still have?
3. Can I effect the exchange? Can I route the piece or pawn to its preferred post? If not, can I remove the obstacles?
4. This is harder! The same questions from the opponents viewpoint!
5. Select "candidate moves" on the basis of these answers. Analyse the tactical consequences of each as far as you are able.

Entire books have been written on this topic. I doubt that anything I may say here can truly answer your question, but one thing I feel sure of is that you need to base your evaluation on more than the static features of the position. And although you are correct to look for negatives, like the possible weak e-pawn after ..d5, remember that unless your opponent is a complete beginner you will not not be able to give weaknesses to him without accepting some of your own. Good luck!
> 7 votes

# Answer
Amazing answer by Philip. But let me try an answer more specific to this position. **Each side has two minor pieces that are developed and quite active.** That knight on d1 is in reality quite good: It is going to e3, blocking the diagonal and eyeing d5 and f5. (I hope you don't, but I personally suffer from this subconscious false idea that a piece is better simply because it is mine!)

So, the question now becomes: **how is each side going to put their heavy pieces (rooks, I mean) to work.** Whoever finds the best half-open files for their rook(s) with potentially weak opponent pawns on them will take the initiative. Now it is a matter of inspection. Begin with the a-file. Can I (Black) open it? Yes, push the a-pawn. But then after exchange, not only white has liquidated their doubled pawn, it is also not clear to whom that file now belongs! So, I will give up on the a-file. Though this might be a good way toward a draw as rooks can be traded along that file. How about b.file? No. I will need many tempi for that, even if it is achievable. Notice that **White is only 2 or 3 moves away from opening their own file:** **the f-file**. So, I must be quick. c5 is interesting and I am not using an engine to see the lines, but maybe after exchanges bxc5 dxc5, the least is White can push c4 and block out our Bishop then continue with their own plan of Ne3 and f4. Philip also mentioned Rf8 and f5, but realistically that is not executable. Case of e, g and h files is pretty obvious. So, it becomes a no-brainer to **play d5! It opens the d file for our rook(s) and a d3 pawn is sitting there**. Moreover, if takes takes, **our Knight becomes amazing on d5** where it at the same time prevents white's plan: it pressures e3 and attacks f4 squares.

So, that is how one would be lead to d5 by asking: **How can I find some play for my rooks.** In chess, and in life, once you ask the right question, it often more easily leads to the right answer :)

Warning: Once you find the plan, check tactical safety first and then move!
> 1 votes

---
Tags: strategy, middlegame
---