Answers.Body: <p>It surely is a measure of the quality of play, the deviation of the game from a "perfect game", as understood by the engine used in the analysis. A perfect move will lose zero units of measure.</p>
  
  <p>I couldn't find a chessbase source, but here it is a similar question on lichess, in which the unit of measure is called a centipawn:</p>
  
  <p><a href="https://lichess.org/qa/103/what-is-average-centipawn-loss" rel="nofollow noreferrer">https://lichess.org/qa/103/what-is-average-centipawn-loss</a></p>
  
  <p>Centipawn loss could also be expressed as percentage, but as your question is about precision, they should be the opposite amount. In your example for white, a precision of 93% equals 7 centipawn loss (7% of inaccuracy).</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-09-11T08:52:26.957Z
Answers.Text: tl;dr : It doesn't mean much. :)
Answers.UserDisplayName: Evargalo
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-09-11T13:59:22.170Z
Answers.Text: @Evargalo The answers in that thread are not too long. Do you mean that precision or centipawn loss measures don't mean much?
Answers.UserDisplayName: Daniel Alfredo Sottile
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-09-11T14:36:30.023Z
Answers.Text: Yes, that's what I mean, I think one shouldn't worry too much about these measures, especially precision aggregated on a whole game. But my comment was rather tongue-in-cheek, don't take it too seriously...
Answers.UserDisplayName: Evargalo
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-09-11T16:30:04.417Z
Answers.Text: Yes, you are right, the average is not meaningful (unless it's close to the ends).
Answers.UserDisplayName: Daniel Alfredo Sottile
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-09-11T18:01:04.703Z
Answers.Text: Could it be that precision is the percentage of moves that coincide with some engine, running under some unknown parameters?
Answers.UserDisplayName: djnavas
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-09-12T10:42:36.110Z
Answers.Text: @djnavas Do you mean the percentage of moves that coincide exactly with the best move according to that engine? I don't think so, because it would be even more useless, as Evargalo said.
Answers.UserDisplayName: Daniel Alfredo Sottile
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-09-10T18:42:41.223Z
Answers.LastActivityDate: 2018-09-10T18:42:41.223Z
Answers.UserDisplayName: Daniel Alfredo Sottile
Body: <p>The game "<em>Salgado L, Iván vs Arroyo R, Jesús, 83rd ESP-ch 1-0</em>", shows this annotation after the last move:</p>
  
  <blockquote>
    <p>Precision: White = 93%, Black = 18%.</p>
  </blockquote>
  
  <p>What does that phrase mean?</p>
  
  <p>Check <a href="https://es.chessbase.com/post/sabrina-vega-y-salvador-del-rio-de-angelis-campeones-de-ajedrez-de-espana-2018" rel="nofollow noreferrer">https://es.chessbase.com/post/sabrina-vega-y-salvador-del-rio-de-angelis-campeones-de-ajedrez-de-espana-2018</a> for more information.</p>
  
Tags: <chessbase><annotation>
Title: What does "Precision: White = nn%, Black = nn%" mean in a game broadcast by chessbase.com?
ThreadText: # What does "Precision: White = nn%, Black = nn%" mean in a game broadcast by chessbase.com?
  
  (Asked by: username_0 on 2018-09-10)
  
  The game "*Salgado L, Iván vs Arroyo R, Jesús, 83rd ESP-ch 1-0*", shows this annotation after the last move:
  
  > Precision: White = 93%, Black = 18%.
  
  What does that phrase mean?
  
  Check <https://es.chessbase.com/post/sabrina-vega-y-salvador-del-rio-de-angelis-campeones-de-ajedrez-de-espana-2018> for more information.
  
  **Tags:** chessbase, annotation
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2018-09-10. Score: 2
  
  It surely is a measure of the quality of play, the deviation of the game from a "perfect game", as understood by the engine used in the analysis. A perfect move will lose zero units of measure.
  
  I couldn't find a chessbase source, but here it is a similar question on lichess, in which the unit of measure is called a centipawn:
  
  <https://lichess.org/qa/103/what-is-average-centipawn-loss>
  
  Centipawn loss could also be expressed as percentage, but as your question is about precision, they should be the opposite amount. In your example for white, a precision of 93% equals 7 centipawn loss (7% of inaccuracy).
  
  > **Comments:**
  > **username_2**: tl;dr : It doesn't mean much. :)  
  > **username_1**: @username_2 The answers in that thread are not too long. Do you mean that precision or centipawn loss measures don't mean much?  
  > **username_2**: Yes, that's what I mean, I think one shouldn't worry too much about these measures, especially precision aggregated on a whole game. But my comment was rather tongue-in-cheek, don't take it too seriously...  
  > **username_1**: Yes, you are right, the average is not meaningful (unless it's close to the ends).  
  > **username_0**: Could it be that precision is the percentage of moves that coincide with some engine, running under some unknown parameters?  
  > **username_1**: @username_0 Do you mean the percentage of moves that coincide exactly with the best move according to that engine? I don't think so, because it would be even more useless, as username_2 said.  
  
  ---
  
  