Wednesday, February 27, 2013

More about manoeuvers

Every tactic can be represented by a geometrical pattern. It contains the targets, the attackers and the road from the attackers to the targets. I call these geometrical patterns the static features of the position. If these patterns actual play a crucial role is decided by typical manoeuvers. The realm of the manoeuvers is governed by the initiative. I summarize this as the dynamics of the game. To give you an idea, it is perfectly possible that a certain position is won when you are to move, while you are lost when it's your opponent to move. This means that looking at the geometrics of the position alone can be very deceptive. We need to know more about the initiative.

The initiative.
Very little is known about the initiative. That's why I take a baffling position that has confused me for long, in order to see if I can find some governing rules.

Black to move.
You can find the problem here.
First I tried to apply some ideas like CCT in relation to the value of the pieces. But that just doesn't make sense. CCT orders the moves by force. The more forceful the move, the higher in the hierarchy. That might be something than can be easely calculated by a computer, but my brain has problems with that. I soon realized that the problems were caused by the fact that to different types of moves are mixed up.

Three ways to win with a tactic.
How do we win with a tactic? There are three ways:
  • Mate the king
  • Capture a piece
  • Promote a pawn
There are moves that are directly related to these three methods and there are moves that are only indirectly related to these three goals. The latter are highly dependend of the initiative. The actual capture is delayed by postponing it. In order to get more favourable circumstances. Every postponing of the cashing in of a tactic is based on the initiative.

Direct moves first.
This means that we first must have an idea about the direct moves, before we can study the indirect ones. In the diagram above, mating the king or promoting a pawn is clearly not the theme. So the position is about captures. There is a natural hierchy of captures: the captures where a piece of low value is traded against a piece of high value first.

This means that the first capture that must be considered is Nxg6. That moves gains a value of +5 (a whole rook) since white is outnumbered on g6. After the gain, the initiative is handed over to white. The knight on f4 was shielding the black queen. Black is outnumbered on f4. Qxf5 Bxf5 Rxf5 leads to a cost of -3 (a bishop) for white. So the most logical sequence of capturing leads to an advantage of +5-3=+2 (the exchange) for black.
If you look at other captures that black can make, it soon becomes evident that he cannot improve on the given line. But maybe white can.

Then indirect moves.
The sequence of direct captures of both sides leads to a -/-2 disadvantage for white. Can he improve on that by postponing the direct captures while maintaining the initiative?
Take for instance 1. ... Nxg6 2.Qe3 threatening the black queen. If black plays the natural 2. ... Qe6 to get out of the way of the white rook and white plays 3.Bxh5 than all of a sudden black is in all sorts of problems. His knight is both pinned against the rook and outnumbered. His king is unsafe.
So black too must not play his most direct move 2. ... Qe6 but he must play 2. ...Rxe5. If black cashes in the queen  now the score becomes +5 (g6) -/-4 (f5) +3 (e5) = +4 for black (RRN vs Q).

Identifying the manoeuvres.
How do these manoeuvres work?
Manoeuver 1.
The problem with cashing in a capture is that it hands over the initiative.
With 1. ... Nxg6 2.Qe3 white abstain from the positive cashing in with 2.Qxf5 Bxf5 3.Rxf5.
In stead of that he introduces two new threats: 3.Rxf5 and Bxh5.
It's very tempting for white to rely on his +6 points (Rp) advantage and to save his queen. The price he pays though is giving up h5, his king safety, and a lot of invasion points for white to use. Alltogether that will proof too much. Especially since black has two undeveloped pieces (Ra8 and Bc8) so effectively he plays with a piece less.

Manoeuver 2.
So black has to answer with a manoeuver of himself.
1. ... Nxg6 2.Qe3 Rxe5 3.Rxf5 Rxf5.
Total cost of this manoeuver: +5 +3 -/-5 so  black gains a full piece. Since h5 is still protected the black king is still safe enough. The weak point of whites manoeuver is that he hasn't captured something during his previous move. He only threathen. But with Rxe5, only two threats remain for white: capture the queen with Rxf5 or capture the rook with dxe5. Both options are favourable for black, value-wise. Both keep the black king safe enough. Black gives some material back, but he doesn't compromises his king safety and het prevent to hand over invasion squares to white. In the end that is a better option. Since the pawnending is winning for black, white must prevent trades too.


4 comments:

  1. It is a CT puzzle.
    CT puzzles are evaluated > 1.75
    So the goal is to get material >1.75

    And now the clue to the puzzle: Black is up in material:

    - 6 to 5 pawns ( +1 )
    - white has in isolated pawn (-0.xx)
    - black has an protected passer (+0.xx)

    So winning the exchange is enough!


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  2. That's not a fruitful way of reasoning if you want to learn something.

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  3. Oh, it is fruitful! At least for your rating at CT.
    You can eliminate variations by reasoning, and that winning the exchange is not enough is kind of reasoning, too.

    However, in a real OTB game we are likely to be happy to find even an +0.5 pu advantage.
    So in a real OTB game it is probably good to follow Dan Heisman:
    "If you found a good move - put it in your pocket and look out for a better one!"
    Of course you can only do so if you have enough time left to spent for looking for better moves.
    I'd say: if you found a good move that might be enough to increase your chances of winning, but it is also kind of tactical move, then you can allow to search deeper. Because you need to be sure that your tactic is really winning and you wont fall for a trap.
    And after you convinced yourself that it is really winning, then you dont need to worry about the extra minute you spend on carefully checking for more tactics.

    But what do you do if you are on "positional thoughts only" mode?
    I have no cure for that. I guess then you simply miss the tactic, isnt it?

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  4. In a real game it is often like this:
    To win material, you tend to exploit the weakness by overstretching your position yourself. After a winning tactic you often have hanging pieces yourself. Or you created a weakness in your position, because if your winning move was positionaly sound, your opponent had seen it and hence not blundered his material away.

    What can you learn from that fact for your real games:
    Whenever you won material and your opponent keeps playing --> Play veeery carefully your next 2 moves. Invest some time (if you have time enough left) such as 2x5 minutes for the next 2 moves - even if it seems ridiculous easy to you. Think hard about any counterchances of your opponent.

    It will safe you many games, but such a behavior would hurt your CT Blitz rating because you would achieve a lot of "yellows" instead of "greens" with that behavior.

    Or the other way round: if you lose material, the best counter chance is after you lost material. To get a clue --> look what the pieces did before the winning tactic, and what job his pieces left unattended in order to cash in the material.
    Then again: the latter advice is useless, because once we are aware we lost the game, we check any possibility for the slightest hope of a chance before we give in and resign.


    For the post: That is all very nice - but what lesson do you intend to learn from it?

    - - - - -
    Other ways to try to improve I can think of:
    Turn your board upside down, and hopefully that makes you more aware of what your opponent can do to you instead of what you can do to him.

    I discovered that my solving times are much slower (factor 3-5!) when I try to solve puzzles upside down (=flipping the board by 180°).
    Uri tried the same and found no difference. He can solve puzzles upside down as good as from bottom to top.

    In the book "chess for Zebras" GM Rowson said he isnt sure how to improve, but one ingredient for improvement he is pretty sure of: You will improve if the training is outside your comfort zone.

    For me it was too painful to solve upside down. I told myself that I want to learn my puzzles first with the normal view, and only after I can do them fast I switch to flipping the board.
    I guess I reached the point where I learned thousands of puzzles, so no excuse anymore. Since it is outside my comfort zone, I am full of hope this is going to be fruitful.
    I could imagine that it improves my boardvision. (So far training my boardvisions attack/defense/check seem to have reached a point where I plateau.)

    Did you try solving known puzzles upside down?

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