Answers.Body: <h1>Space advantage</h1>
  <p>There is an important difference between space advantage and other kinds of advantage - it's very hard to convert it into something tangible. While play with material advantage (exchange pieces, win the endgame) or with iniative advantage (attack, sacrifice, checkmate) is in principle straightforward, it is not so with space. Space gives you more room to maneouver and easier development, but that is not enough to win by itself - you still need to break through on the side where you have more space for it too matter (or open up the center and win the resulting open position with better placed pieces).</p>
  <p>And let's not forget that in these openings White doesn't get space advantage for free - in all of them Black has significiant counterplay.</p>
  <h1>Computer evaluation and practical play</h1>
  <p><a href="https://www.iccf.com/" rel="nofollow noreferrer">ICCF</a> correspondence play allows use of engines. I think that best indicator of line's theoretical health is looking at recent results in it between high-rated (+2400) ICCF players. What we see is that King indian defence leads mostly to draws, so White's space advantage is offset enough by Black counterplay.</p>
  <p>Let me put it that way: if you tell me that some position is +1 by engine in Italian opening I won't be surprised if White wins. If you tell me the same about some topical King indian position, that is matter of course and I will be surprised if Black fails to draw.</p>
  <p>Personally I haven't lost in KID on ICCF yet, my only issue with it is that you reach positions, that neither you nor your engine understands, so it's really hard to play - you cannot just copy engine moves and know that you will be okay, like you can do in Ragozin for example.</p>
  <p>For OTB engines' opinion matters even less, especially at amateur level. Of the openings you listed I think Pirc is today considered the most dubious, but it still occupies an important niche in practical play - it is the weapon of choice against lower rated players in must win situations for a lot of players, since it keeps the pieces on the board. White gets advantage of course, but once they make some mistakes and you equalize, there is still enough material on the board to play for the win. You cannot say this about Moscow variation of the Sicilian for example, where Black has hardtime generating winning chances even against clumsy play by White.</p>
  <h1>Do engines overrate space advantage?</h1>
  <p>In the past, in the days of handcrafted evaluation functions, this was most certainly true. Today, when evaluation is NNUE blackbox it's hard to say. I would say that for KID at least, they still overrate space advantage, since KID-s get way more draws than you would expect solely from engine evaluation. In general as long as evaluation is under +1.5 in KID-s I still believe in my drawing chances.</p>
  
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Answers.Text: So is it safe to somewhat ignore engine evals at least in the KID? Because I don't want to play the samisch gambit for eg as black which is the best line for black engine wise, netting white a edge of 0.3
Answers.UserDisplayName: anti - Marshall
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Answers.Text: In mainline KID I consider evals between 1.0-1.5 playable even on correspondence chess.  In positions with open center or with c5 I think engines are a bit more reliable. Samisch gambit for black is perfectly sound, just a bit dry if white accepts it. +0.3 isn't really an edge in most scenarios though - that's practically zilch.
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Answers.Text: Thanks, King's Indian mayhem, here I come
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Answers.Body: <p>I have often noted that the engines value space. Do they overvalue space? No, they value it exactly correctly for their level. The correct answer is that humans undervalue space. No human plays at a 3600 level. Therefore, it is humans that are incorrect, not the engines.</p>
  <p>That said, at my level (2200), I often discount the engine evaluation for a variety of reasons, space among them. If you play a variety of King's Indian setups, the engine will hate your position. But, against humans, they are very playable setups even at the highest level. (You will notice Nimzo and KGD are played far more often, however).</p>
  
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Answers.Text: Your gist is that those evals are somewhat abstract and irrelevant for humans? With that in mind is it OK to play those positions ?
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Answers.Text: They are not human comprehensible. The highest rated human is ~2850. So, let's assume his true playing strength is 3000. That's still 600 points or more below the engine. Thus, even playing at a 3000 strength, the human cannot fully understand the engine evaluation in many cases. There are many instances of humans playing those positions even at the highest level. So, unless your opponent is rated 3600, I think you will be fine. :)
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Answers.Text: @JPAlioto a bit pedantic point: there is no connection at all between human and engine ratings - they are computed differently, on different scale, based on different events. Engine rated 3600 is not 800 points higher rated than 2800 human player, that's like saying that 120 degrees Fahrenheit is 90 degrees warmer than 30 degrees celsius.
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Answers.Text: @MatijaSirk It's not completely unrelated. We have matches against human GMs and it's built up from there. But, because of the way ELO works, it breaks down at the extremes. Is SF16 3600 FIDE? No way to know. Suffice it to say, if SF16 entered human tournaments it would likely win every game.
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Body: <p>In openings such as the closed Tarrasch and the KID or the pirc , engines often show an advantage for white of around 0.5 ( a bit higher generally), I remember reading around 5 years ago and this is a opinion I have heard from other strong players as well that engines tend to overestimate space as an advantage, is there any truth to this statement now or have Neural networks rendered these statements obsolete and if yes, does that put these openings in the litter box of chess history?</p>
  
Tags: <opening><engines>
Title: Understanding engine evals in positions with less space
ThreadText: # Understanding engine evals in positions with less space
  
  (Asked by: username_0 on 2024-01-30)
  
  In openings such as the closed Tarrasch and the KID or the pirc , engines often show an advantage for white of around 0.5 ( a bit higher generally), I remember reading around 5 years ago and this is a opinion I have heard from other strong players as well that engines tend to overestimate space as an advantage, is there any truth to this statement now or have Neural networks rendered these statements obsolete and if yes, does that put these openings in the litter box of chess history?
  
  **Tags:** opening, engines
  
  
  ---
  
  ## 2 answers
  
  ### Answer by username_1 on 2024-01-31. Score: 2 | Accepted answer
  
  # Space advantage
  
  There is an important difference between space advantage and other kinds of advantage - it's very hard to convert it into something tangible. While play with material advantage (exchange pieces, win the endgame) or with iniative advantage (attack, sacrifice, checkmate) is in principle straightforward, it is not so with space. Space gives you more room to maneouver and easier development, but that is not enough to win by itself - you still need to break through on the side where you have more space for it too matter (or open up the center and win the resulting open position with better placed pieces).
  
  And let's not forget that in these openings White doesn't get space advantage for free - in all of them Black has significiant counterplay.
  
  # Computer evaluation and practical play
  
  [ICCF](https://www.iccf.com/) correspondence play allows use of engines. I think that best indicator of line's theoretical health is looking at recent results in it between high-rated (+2400) ICCF players. What we see is that King indian defence leads mostly to draws, so White's space advantage is offset enough by Black counterplay.
  
  Let me put it that way: if you tell me that some position is +1 by engine in Italian opening I won't be surprised if White wins. If you tell me the same about some topical King indian position, that is matter of course and I will be surprised if Black fails to draw.
  
  Personally I haven't lost in KID on ICCF yet, my only issue with it is that you reach positions, that neither you nor your engine understands, so it's really hard to play - you cannot just copy engine moves and know that you will be okay, like you can do in Ragozin for example.
  
  For OTB engines' opinion matters even less, especially at amateur level. Of the openings you listed I think Pirc is today considered the most dubious, but it still occupies an important niche in practical play - it is the weapon of choice against lower rated players in must win situations for a lot of players, since it keeps the pieces on the board. White gets advantage of course, but once they make some mistakes and you equalize, there is still enough material on the board to play for the win. You cannot say this about Moscow variation of the Sicilian for example, where Black has hardtime generating winning chances even against clumsy play by White.
  
  # Do engines overrate space advantage?
  
  In the past, in the days of handcrafted evaluation functions, this was most certainly true. Today, when evaluation is NNUE blackbox it's hard to say. I would say that for KID at least, they still overrate space advantage, since KID-s get way more draws than you would expect solely from engine evaluation. In general as long as evaluation is under +1.5 in KID-s I still believe in my drawing chances.
  
  > **Comments:**
  > **username_0**: So is it safe to somewhat ignore engine evals at least in the KID? Because I don't want to play the samisch gambit for eg as black which is the best line for black engine wise, netting white a edge of 0.3  
  > **username_1**: In mainline KID I consider evals between 1.0-1.5 playable even on correspondence chess.  In positions with open center or with c5 I think engines are a bit more reliable. Samisch gambit for black is perfectly sound, just a bit dry if white accepts it. +0.3 isn't really an edge in most scenarios though - that's practically zilch.  
  > **username_0**: Thanks, King's Indian mayhem, here I come  
  
  ---
  
  ### Answer by username_2 on 2024-01-30. Score: 0
  
  I have often noted that the engines value space. Do they overvalue space? No, they value it exactly correctly for their level. The correct answer is that humans undervalue space. No human plays at a 3600 level. Therefore, it is humans that are incorrect, not the engines.
  
  That said, at my level (2200), I often discount the engine evaluation for a variety of reasons, space among them. If you play a variety of King's Indian setups, the engine will hate your position. But, against humans, they are very playable setups even at the highest level. (You will notice Nimzo and KGD are played far more often, however).
  
  > **Comments:**
  > **username_0**: Your gist is that those evals are somewhat abstract and irrelevant for humans? With that in mind is it OK to play those positions ?  
  > **username_2**: They are not human comprehensible. The highest rated human is ~2850. So, let's assume his true playing strength is 3000. That's still 600 points or more below the engine. Thus, even playing at a 3000 strength, the human cannot fully understand the engine evaluation in many cases. There are many instances of humans playing those positions even at the highest level. So, unless your opponent is rated 3600, I think you will be fine. :)  
  > **username_1**: @JPAlioto a bit pedantic point: there is no connection at all between human and engine ratings - they are computed differently, on different scale, based on different events. Engine rated 3600 is not 800 points higher rated than 2800 human player, that's like saying that 120 degrees Fahrenheit is 90 degrees warmer than 30 degrees celsius.  
  > **username_2**: @MatijaSirk It's not completely unrelated. We have matches against human GMs and it's built up from there. But, because of the way ELO works, it breaks down at the extremes. Is SF16 3600 FIDE? No way to know. Suffice it to say, if SF16 entered human tournaments it would likely win every game.  
  
  ---
  
  