FIDE May 2017 - Miguel Illescas - Working With Computers PDF

 

Miguel Illescas: Working with computers: does the machine fool us?

held his breath at the verdict of the engine, which offered a dead equal evaluation of 0.00, a consequence of the repetition of moves that occurs in the curious line

Farewell to glamour? 20...Nf2! 21.Kg2 Nh4!

In recent years, increasingly powerful

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computers programs are already able unravel theand mysteries of most positions into just a few seconds. This has led to the trend of following the major tournaments live  broadcasts with the engine connected, which  judges implacable every movement made by the grandmasters. The fan, standing on the shoulders of giants, thinks he is a big shot and criticizes Carlsen strongly for missing a tactical blow, or Karjakin, for not being able to see it. “What a patzer! It was so easy…” He easy…”  He shouts in disbelief, almost outraged. For instance, let’s take the already famous 20 ... Nf2 that could have given a beautiful draw

9r+ rz rk+0 k+0 9+p+++t p 0 9 +pz ppw ppw q z p0 p0 9z p + z p + 0 9P+ +P+ s n0 n0 9+ PPs P zPs N z P 0 9 P z NQs N sQs nKz nKz P0 P0 9t R + +R+ 0 xiiiiiiiiy

to Karjakin in the tenth game, which he ended up losing. It was tremendously criticized by all and sundry, even by grandmasters. Was it really that easy?

equality!  equality! 

Carlsen : Karjakin WCC New York (10) 2016

XIIIIIIIIY 9r+ + t rk+0 rk+0 9+p+ + z p 0 9 +pz ppw ppw qnz qnz p0 p0 9z p ++P+ z p ++0 0 9P+ 9+ PPs P zPs N z Pn0 9 P z s NQz NQz P z P0 P0 9t R + +R+K0 xiiiiiiiiy In this position, the game continued with 20 ...d5 21.Qh5 Ng5 22.h4 Nf3 23.Nf3 Qf3 24. Qf3 Rf3 25.Kg2, a very natural sequence of moves that led to a slightly better endgame for white, which Carlsen went on to win in good fashion. While Karjakin was thinking about his twentieth move, the audience on the Internet FIDE Surveys – Miguel Illescas

22.Kg1 Nh3! 23.Kh1 Nf2! 24.Kg1 Nh3  with

But Karjakin finally played pla yed the natural 20...d5, and before we had recovered from the excitement Carlsen answered quickly with the incisive 21.Qh5 (instead of the prudent 21.f3), which still allowed the capture on f2, which again was correct. Social networks set on fire! The audience was pulling their hair out. How is it possible that the two finalists of the World Championship do not see something so obvious? Could be read on the net. I will rhetorically repeat the question. Was it really that obvious? How to estimate the difficulty of a combination? Of course, the machine sees the truth on the spot and the lines that it offers do not admit any discussion whatsoever. But let us review the analysis step  by step, for a better understanding. 20...Nf2!  Is an ugly move, which leaves the knight  pinned and apparently lost after the obvious obvious 21.Kg2  Here, most masters stop the analysis, because experience tells us that the knight is lost in these cases, except for a miracle. And the miracle exists as a sacrifice: 21...Nh4!!   based on the fact that after 1

 

22.gh4 Qg6

XIIIIIIIIY 9r+ + t rk+0 9+p+ + z p 0 9 +pz pp+qz p0 9z p + z p + 0 9 P0 0 9P ++z P+ PP s N++z 9 P z s NQs nKz P0 9t R + +R+ 0 xiiiiiiiiy the white king has nowhere to hide, since the  black knight deprives him of h1 and h3, and white must return the material with interest.  interest.  Once seen, it seems easy, but there are no referents in the grandmaster’s mind mind to imagine the jump to h4, which leads to a very rare combination. I took the trouble to search the Mega2017 database for a similar pattern: knight sacrifice on h4 to give a check on g6, with a knight on f2. In almost seven million games, do you know how many I found? ZERO. Not a single time in the history of chess competition there have been a similar combination. Thus, it is not surprising that Karjakin's mind almost automatically dismissed the "ugly" catch in f2. And what about the "missed" chance in the next move? Logically, if neither of the two contenders noticed the blow in the 20th, they wouldn’t see it in the 21st. Because it was harder, indeed! After 20 ...d5 21.Qh5

XIIIIIIIIY 9r+ + t rk+0 9+p+ + z p 0 9 +p+pw qnz p0 9z p +pz p +Q0 9P+ +P+ +0 9+ z PPs N z Pn0 Pn0 9 P z s N z P z P0 9t R + +R+K0 y xiiiiiiii  21…Nf2! 22.Kg2

Black had to anticipate: FIDE Surveys – Miguel Illescas

22...Qf7!  which is the only move. And the next one one is diabolical, since after: 23.Kg1 

XIIIIIIIIY 9r+ + t rk+0 9+p+ +qz p 0 9 +p+p+nz p0 9z p +pz p +Q0 9P+ +P+ +0 9+ z PPs N z P 0 9 P z s N s n z P0 9t R + +Rm K 0 xiiiiiiiiy The only move that keeps the equality is the quiet: 23...Qf6!! to answer 24.Ng4 (or 24.Nd1) with 24...Qg5!!  Since it turns out that after 25.Qg5 Nh3 the knight is saved. Hurray for the engine! But it is difficult to find this kind of unusual moves when there are reasonable alternatives like 20...d5. The title "Farewell to glamour" is more than  justified. With the engine on, anyone anyone believes to know the truth and presumes to have the authority to criticize nothing less than the world champion. A pity, in my opinion, which makes me feel a bit of nostalgia for those years in which fans and the press spent several se veral months in order to refute a sacrifice by Mikhail Tal. Lastly, I would like to tell you briefly the following anecdote. Karjakin has just lost the tenth game and is obliged to deal with the TV channels, first. The journalist approaches him and asks in an excited tone: "What can you tell me about the blunder on move 20 when you  pushed your pawn to d5?" He asks the question as if he asks the striker st riker how he could miss an easy goal. Karjakin doesn’t understand anything, and he cautiously replies, "I’m not sure what do you mean, but I certainly have not lost because of a move as natural as 20 ... d5." The journalist journalist didn’t know what to answer.

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MATHEMATICAL EVALUATION vs PRACTICAL EVALUATION

To play chess well, and of course to analyze, you need to be able to evaluate a position well. To do this we must consider several factors, the most obvious being the king’s safety and the material balance. Almost from the  beginning, engines engines also computed the concept of piece activity, which is essential, and nowadays modern programs also take into account countless factors, structural and dynamic. However, despite all the improvements, engines are still much more reliable in the move they come up with than in the evaluation they offer. It often happens that, when developing a line, the engine corrects its initial evaluation by clearing the calculation horizon. How does the engine evaluate a position?

For each position the engine adds and subtracts all good and bad from each side,  besides the material: if your king is not safe, the evaluation drops, even if there is no immediate attack. If your knight could be installed in a weak enemy square, the evaluation raises. With doubled pawns, it goes down, again. And so, hundreds and hundreds of factors. After narrowing down the calculation to the limits allowed by the engine and mixing all the factors into the shaker, the  program gives a score to each branch of the line’s tree, giving a value in pawn units, with their decimals. Finally, the engine offers a numerical and strictly mathematical evaluation of the position. But this is not always enough for the human player. What does an equality assessment mean in a situation of tactical madness, if we need to find several only and strange moves, obvious to the engine but almost impossible for a human made of flesh and blood? Let’s remember again the great Mikhail Tal, when he admitted that perhaps

The idea then arises: the chess player needs a  practical assessment of the position.  Not just the acknowledgment that the position is winning, but whether it is easy or not to  play, taking into account the probability probability of either side to make a mistake. Take as an example the position that occurred in the most decisive game of the last World Chess Championship, the third of the tiebreaker. A critical moment was reached after the 36th move by black. Carlsen had sacrificed a pawn for great compensation. Karjakin : Carlsen WCC New York (play-off, 3) 2016

XIIIIIIIIY 9r+ + + k0 k m0 9+ p z + z p 0 9 + p z + z p0 p0 9+P+P+ 0 9 +Lw qPz qPz p++0 9+ + s nP+P0 nP+P0 9 + +Q+Pm K0 K0 9+ R t + + 0 xiiiiiiiiy Here the engine evaluates the position as equal, which may be strictly true from an absolute point of view, but it is obvious that it is much easier to play for black. White must keep a stubborn defense, and even in the best case scenario, exchanging the active enemy’s major pieces, with that awful bishop they could only dream of getting a draw. As we know, Karjakin blundered and lost in  just three moves. 36.Qe1? According to the engine, white resists with  passive moves such as 36.Bd3 or 36.Ba2. 36.Ba2. 36...Qb2 37.Bf1 Ra2 38.Rc7 Ra1 0:1.  Let's see another example of incorrect evaluation from the human point of view, also from the same match.

his combination was not perfect, but it caused insolvable problems to his opponent. FIDE Surveys – Miguel Illescas

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Carlsen : Karjakin WCC New York (8) 2016

XIIIIIIIIY 9 + + + +0 9+ + + m k 0 9Q+ + + z p0 q+P+ s n ++0 0 9++w 9z p + + z PP0 PP0 9 + + +Lm K0 9+ + + + 0 xiiiiiiiiy According to the engines working at great depth, the position is more or less equal after 51.Qb7 or 51.h4. The truth is that defending this position with white is a nightmare, and it is clear that with that colossal knight and the mighty pawn on a3 Black has no risk of losing. The most likely outcome is for white to end up winning, for instance, bringing the white king to support his pawn after a series of countless checks, a journey far beyond the horizon of calculation of the engine. As we know, the game ended quickly after the  blunder 51.Qe6? h5! 52.h4 a2!   And Carlsen resigned, because even after capturing the pawn he remains in a mating net 53.Qa2 Ng4 54.Kh3 Qg1 55.Qb2Kg6! 

Evaluation, according to the engine: 0.00 total equality. But the vast majority of players would be unable to save this ending! It is a sequence of six only moves in order for Black not to lose: 1...Kf3! 2.f6 Qg8!  2...Kg4 3.Qe7! Qb8 4.Qb4; 2...Qf7 3.Kb4 Kg4 4.Qe7 Qa2 5.f7 Qb2 6.Ka5 Qa2 7.Kb6 Qb3 8.Kc7 Qc4 9.Kd8 winning. 3.Kc3 Kg4! 4.Qe7 Kh5! 5.f7 Qg3 6.Kc4 Qf4!  And black follows the narrow path that leads to the draw. Would it be feasible for the programs to offer a practical assessment? The player that is oriented by the engine would do better to look not only at the evaluation of the best move, but also at the next two or three best, and deepen the forced lines to check if one of the sides is "on the  brink of the abyss”. In that case, even if the engine announces equality, it is advisable to be suspicious of the line.

We find the same evaluation problem in endings like those with Q+P : Q. Many of them are draws, but the strong side usually ends up winning, because the defense needs an extreme precision.

XIIIIIIIIY 9 + + w q +0 9+ + + + 0 9 + + + +0 9+ + w QP+ 0 QP+ 9 + + + +0 9+K+ + + 0 9 + + m k +0 9+ + + + 0 xiiiiiiiiy Black to play.  FIDE Surveys – Miguel Illescas

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10 TIPS ON HOW TO ANALYZE WITH THE ENGINE 1. Always look first at the position objectively, thinking for yourself, without being influenced by the module. 2. Enter the move that you would play, even if it is not among the suggested ones, to see s ee the answers offered; develop the different lines in order to understand the real value of your move. 3. Ask the program to show you the best three or four moves, to get a quick overview of the  position. 4. Do not take the engine evaluation for granted, for it is only a guidance. It is more important to guess the practical assessment ass essment and whether the position is easy eas y to play or not. Small differences in the evaluation should be dismissed as a real advantage. 5. In general, do not let the engine think for more than two or three minutes per move. It is necessary to go on by making the main move, especially if its evaluation is significantly superior to the one that follows, and to develop the different lines. 6. Stop the analysis when both when both sides start to have a lot of moves of equivalent value. It It doesn’t make sense to spend a lot of time with the program in quiet positions. 7. In tactical situations, the evaluation is not reliable until the position stabilizes. stabilizes . We will know that an evaluation is stable when several of the best moves offer a similar value, and so does the opponent's response. 8. When the engine takes a long time to step up to the next level of depth, it is a good time to move forward or stop the analysis and come up with a conclusion. 9. It is a good idea to write the lines, reviewing them slowly, trying to understand the meaning of each move, until we are able to write down our evaluation into words or symbols, discarding the rest of the moves. 10. Do not do anything else while analyzing, because the concentration is interrupted and we could forget what we have learned in the process. It doesn’t work to leave the engine analyzing to spend time on Facebook!

FIDE Surveys – Miguel Illescas

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