Threat Based Evaluation Process

1. What are my opponent’s threats?
    a. Is there a mate threat?
    b. Is there a threat of material loss?
    c. Is there a tactical threat?
    d. Is there a positional threat?

2. Do I have any threats I can execute?
    a. Is there a mate threat?
    b. Is there a threat of material loss?
    c. Is there a tactical threat?
    d. Is there a positional threat?

3. Based on my threat analysis I need to compare both my threats versus my opponent’s and come up with a plan based on:
    a. ignoring opponent’s threat
    b. creating a counter threat
    c. stopping opponent’s threat

4. If neither I or my opponent have any threats, then I proceed to a positional evaluation of the position which can be based on either Silman’s imbalances or Karpov’s method.

[The evaluation method for sub 1800 players  might be simplified to focus on piece activity and harmony...but I need to look into this further.]

Threats in Chess Pt. 1

We make a mistake when we think of bishop pair advantages or of knight outposts before we consider all of our opponent’s threats. The result is our knight getting to a wonderful central outpost, but on the next move our opponent forks our Queen and King and we lose yet another game. While positional knowledge is important and required, particularly at the +1800 level, recognizing threats and having good tactical vision is more important to winning games at the <1800 rating level.

This does not mean that you need to spend your entire game reacting to your opponent’s threats, this will only cause you to play a dull defensive game dictated by your opponent’s moves. What this means is that on every move you need to ask yourself, “What is my opponent threatening?” and “What is the consequence of my opponent’s last move?”. Once you identify your opponent’s threats and plans you need to decide how you are going to react to your opponent’s plan and how it relates to your own plans.

According to Dan Heisman, there are three things one can do against a threat:
1. Ignore it
2. Create a bigger counter-threat (counterattack), or
3. Stop it.

The point is not to play your game based on your opponent’s moves, but to always be very aware of what your opponent is trying to do, and to either prevent it or continue with a more threatening response of your own. What you cannot do is not consider the threats your opponent is making, and then end up playing a positional move or a rule of thumb move which causes you to lose the game. Hopefully, by simplifying our thought process we can play better chess.

Below is a combination of the Crafty chess engine algorithms as well as Larry Kaufman’s material evaluation processes which is used by the Rybka engine.

Pawns

Pawn = 1

isolated pawn penalty based on file:
a-pawn : -.12
b-pawn : -.14
c-pawn : -.16
d-pawn : -.20
e-pawn : -.20
f-pawn : -.16
g-pawn : -.14
h-pawn : -.12

Doubled pawn (and not also isolated) penalty of -.12 plus add isolated pawn penalty

Backward pawns -.06 penalty +.04 bonus for attack on backward pawn on semi-open file.

Pawn advance in center +.04 / rank increasing to about +.08 / rank in the endgame
Development

Rook pawn is worth 15% less than a regular pawn (.85 of a pawn) (L.Kaufman)

Knights

Knights = 3.25
Centralized knight: +.30
In outpost : +.08

Unpaired knight is worth approximately 3.14 pawns (worth less) (L.Kaufman)

Bishops

Bishops = 3.25
Bishop in endgame +.10
Bad bishop : -.04
Corner bishop : 0.0
Center bishop: +.3
Attacking / good bishop: +.18
Attack against King: +.05

The Bishop Pair

Bishop pair: +.50  Bishop pair is worth .50 more if not pieces exist to exchange them (L.Kaufman)

Bishop pair is worth less than .50 a pawn when most or all of the pawns are on the board, and more than .50 pawns when half or more of the pawns are gone (L.Kaufman)

If you have the bishop pair, and your opponent’s single bishop is a bad bishop (hemmed in by his own pawns), you already have full compensation for 1 pawn (L.Kaufman)

Unpaired bishop is worth approximately 3.14 pawns (worth less) (L.Kaufman)

Rooks

Rooks = 5
Attacking on open-file: +.20
One semi-open file: +.10
On open-file: +.14

Rook and Bishop is better than the Rook and Knight. (L.Kaufman)

Queen

Queen = 9.75

Queen and Knight is slightly better than Queen and Bishop

King
Centralized in opening: -.24
Centralized in endgame: +.36
On open file in opening: -.23
No adjacent pawns: -.08

Special Cases

Hanging pieces: -.10

Exchanges favor the side with a material advantage

Minor pieces lose their value as the endgame approaches

In endgames with no other piece the bishop is worth about 2.5 and the knight 2.25 with other pieces the minors are worth about 3.25

Rooks gain value as the endgame approaches

Note: I have modified the Crafty point values to reflect the Kaufman values.

Resources

Evaluation of Material Imbalances in Chess

GNU Chess Positional Heuristics

http://chessprogramming.wikispaces.com/Evaluation

http://www.chessvariants.com/d.betza/pieceval/index.html

Feel free to leave comments if you have any suggestions to improve the checklist.

When solving a tactical puzzle of intermediate to advanced level I either:

1. Have no clue how to go about solving it and get it wrong.

2. Have multiple ideas that look promising, but after further analysis don’t win {usually end up playing one of the two and get the answer wrong}.

3. Solve the puzzle correctly.

This post is going to focus on solving the 2nd category above. I have found that you will get many more puzzles correct by combining ideas that arise by analyzing different candidate moves. Unfortunately, by not making a link between the two, or forgetting about your first idea when looking at the second, I mainly fail to connect the dots and only after reviewing the correct answer do I see that I had been on the right track and would have answered correctly  if I had combined my candidates.

You might want to solve this puzzles on your own before reading the answers below taking into account your thought process while doing so and then see if you encountered the same issues as I did.

Here’s the first position we will look at:

White to move and win

The first candidate that came to mind was 1.Bb6 attacking the Queen. I analyzed the response 1…Nxb6 2.axb6 Qxb6 which loses a pawn for White and the Black Queen lives on. So I abandoned this candidate and looked for a better move.

I then found that Qh6 looked promising and I began to analyze 1.Bh5 with the idea of Bh8 and then getting my Queen to h6. But I soon found that 1.Bh5 was a slow since it allows 1…Kh7 and White is out of gas. What I missed, and where I think there is room for improvement, is if I would have combined both moves. Attacking the Black Queen with 1.Bb6 with the idea of freeing the diagonal for my Queen to get to h6 with mate was the winning combination and one I failed to see by not connecting the dots.

Let’s look at another example, and one which occurred right after I had attempted to solve example #1 above.

White to move and win

In this position quickly saw that both the White rook and Queen were attacking the Black d8 rook, and that there might be a tactical opportunity if the Queen were deflected from its defense. The candidate that came to mind was 1. b4 but after further analysis I saw that the Queen could seek shelter by moving to 1…Qc7.  The other candidate that stood out was 1.Qf6+ but the King can easily get out of the way with 1…Kg8 and there aren’t enough White pieces in the vicinity to force the issue. The third candidate I analyzed was attacking the undefended bishop with 1.Qe7 but I found that the bishop can get out of harms way via 1…Bc8. If I would have combined the two ideas or even looked a few ply deeper  I would have found the answer 1.Qe7 attacking the bishop and preventing the Queen from seeking shelter at c7 after deflecting her with b4. 1…Bc8 2.b4! and Black resigned.

Critical Moments (Dorfman)

• Positions where there are possible exchanges.
• Change in pawn structure (especially central pawns).
• At the end of a  series of forced moves (combination).
• Transposition into an endgame.

 A ply is a half move and a move is equivalent to 2 ply or a turn by each player. For example,  1. e4 is one ply and 1…e5 would be the 2nd ply, together these two plys make one move.

Getting close to the truth of a chess position requires the calculation of a minimum of 6 ply (3 moves). The higher your rating the higher the ply calculation requirement increases since your opponent will be delving more deeply into the position than you. If you calculate anything less than 3 ply you are playing hope chess, since you are not forseeing your opponent’s responses. 

Below is an assessment of how calculation skill correlates to one’s chess rating:

0-1000 1 ply

1000-1200 2-3 ply

1200-1400 4 ply

1400-1600 6 ply

1600-1800 8 ply

1800-1900 10 ply

1900-2000 12 ply

Stopping your calculations too soon can prevent you from finding the winning move. Many times the winning move comes after a series of seemingly unfavorable moves, and stopping your calculation too soon will prevent you from finding the best move in the position. At the same time, not looking deeply enough into your opponent’s moves will cause you to miss defensive opportunities against your opponent’s threats.

Here’s a good example of a tactics puzzle where I did not find the correct answer because I stopped my calculations 1 ply too soon.

In this position I saw 1. Qxe5 and 1. Rd8+ as possible candidate moves. I then proceeded to analyze 1.Qxe5 Qxe5 2.Rd8+ which leads to the next position:

At this point I saw that the Black King seemed to be escaping via 2…Ke7 and he would also be attacking the undefended rook on d8. I stopped my calculations at this point and proceeded to analyze 1.Rd8 which also lead nowhere. If only I would have continued analyzing 1 ply deeper, I would have found 3.Re8# and White Wins. Here’s the winning position:

Consistently calculating at least 6 ply deep on most moves is one of the key improvements you can make in your thought process that will allow you to improve your chess skill.

I modified the process based on conversations with FM Charles Galofre, I have merged the tactical and strategic scans into one. His point is that even if you find a strong tactical move, you should still look at the strategic aspects of the position since the game might be won with a quiet positional move which you would not have considered if you cut your search short once you had found a tactic.

The following is the thought process I have decided to employ during long games. The idea is to drill these questions in during practice, so that they become second nature when playing an regular game.

The idea is to create your own thought process checklist and make it your own.

It is highly recommended that you also check out Chessplanner by Blue Devil Knight, since it is more thorough than my checklist.

1. Threat Scan

I. What is my opponent threatening?

II. What are the consequences of my opponent’s last move? (how has the position changed?)

III. Do I have any checks, captures or threats (CCT)? Consider forcing moves as possible candidates

2.  Move Scan

A. Tactical Scan

I. Is there likely to be a tactic in the position?

a. Tactical Motifs: hanging pieces, weak back rank, discovered attack, pinned or skewerable along same rank, overworked pieces, lack of development, poorly guarded pieces, overworked pieces, forks, weak king position (uncastled King), large accumulation of pieces on one side, in-between moves.

Even if you find a strong tactical scan, if time allows do a positional scan. If you find a good move look for a better one.

B. Strategical Scan

(If there are no tactics, you need to come up with a plan)

I. Material balance

II. King safety

III.  Pawn structure

a. Who has the better pawn structure (look for doubled pawns, isolated pawns, and hanging pawns)
b. Are there any open lines or diagonals?
c. What are the strong and weak squares?
d. Who is controlling the center?
e. Who has more space and where on the board do they have it?

IV.. Activity
a. which pieces are active and which are not? (how can you make them more active)
b. Who has better development?
c. who has the initiative?

V. Minor pieces
a. Bishops (bishop pair, bad / good bishop, good diagonals for bishops)
b. Knights (outposts, strength compared with bishops)

VI. misc questions
a. what stage of the game are we in?
b. If we removed the Queen’s off the board, who has the better endgame?

4. Select your candidates (based on scans above)

5. Analyze candidates (start with the most forcing)

6. Select move based on analysis

7. Blundercheck

8. Write down your move

9. Blundercheck again

10. Make your move

The following thought process which is recommended by Karpov and Mazukevich is used to detect the important features of an arbitrary position in order to devise a plan that conforms to the positional assessment derived by using this thought process.

This thinking process is based on 7 criteria in which the White position is compared with the Black position.

1. What is the material balance?

2. Are there any (direct) threats?

3. How is the safety of both Kings?

4. Pawn structure questions:

   a. Where are the open lines and diagonals?

   b. Are there many strong squares?

   c. Who is controlling the center

   d. Who has more space and where on the board do they have it?

5. Which pieces are active and which are not?

Training applications:

Go through the questions out loud while doing middlegame positions based on  Stoyko Exercises. The idea is to practice “talking out loud” with the list in front of you so that when you are in real game mode the questions will be asked subconsiously.

Source: Chess Strategy for Club Players pg. 37.