Answers.Body: <p>FIDE apply a monthly update of rating but, during matches or tournaments, the ratings of participants it remains unchanged until the event is completed.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-12-19T22:34:20.897Z
Answers.LastActivityDate: 2018-12-19T22:34:20.897Z
Answers.UserDisplayName: Mario
Answers.Body: <p>The exact workings of FIDE rating calculations can be found <a href="http://www.fide.com/component/handbook/?id=172&amp;view=article" rel="noreferrer">in the official rules</a>. As you can see in Table 8.1b, a rating difference of 3 points (as is the case with Carlsen-Caruana) means that both players have the same expected score: 0.5. The value of ΔR, which is the expected score minus the result (in the case of a draw, 0.5) is therefore 0.5-0.5=0, i.e. no change in rating.</p>
  
  <p>If instead their difference were 4 points rather than 3 (meaning that Carlsen's expected score would be 0.51 instead of 0.5), a draw would mean that his ΔR would be -0.01. With a K value of 10 (as he has a rating above 2400), his gain/loss would therefore be -0.01*10. In other words, a draw with a rating difference of 4 would mean that he would lose 0.1 rating point (whereas Caruana would gain 0.1 point).</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-11-14T18:52:15.840Z
Answers.Text: If the ratings weren't that close, would they have changed already, or do they wait until the match is over?
Answers.UserDisplayName: itub
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-11-14T19:37:15.933Z
Answers.Text: Officially, it's neither, as FIDE only updates their ratings once a month (per their official rules). However, it is possible to calculate real-time ratings after each individual game, as in done by [this site](https://2700chess.com/) for example.
Answers.UserDisplayName: ATLPoly
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-11-14T15:45:52.127Z
Answers.LastActivityDate: 2018-11-14T17:46:56.847Z
Answers.LastEditDate: 2018-11-14T17:46:56.847Z
Answers.UserDisplayName: ATLPoly
Body: <p>By now there were 4 games and all were drawn. Should it not mean that Caruana should get points?</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2018-11-14T15:19:51.377Z
Comments.Text: They are too close in rating. Any change in draw is within rounding errors.
Comments.UserDisplayName: SmallChess
Tags: <rating><world-championship>
Title: Why don't the ratings of Carlsen and Caruana change after 4 games in the WCC 2018?
ThreadText: # Why don't the ratings of Carlsen and Caruana change after 4 games in the WCC 2018?
  
  (Asked by: username_0 on 2018-11-14)
  
  By now there were 4 games and all were drawn. Should it not mean that Caruana should get points?
  
  **Tags:** rating, world-championship
  
  > **Comments:**
  > **username_1**: They are too close in rating. Any change in draw is within rounding errors.  
  
  ---
  
  ## 2 answers
  
  ### Answer by username_3 on 2018-11-14. Score: 9 | Accepted answer
  
  The exact workings of FIDE rating calculations can be found [in the official rules](http://www.fide.com/component/handbook/?id=172&view=article). As you can see in Table 8.1b, a rating difference of 3 points (as is the case with Carlsen-Caruana) means that both players have the same expected score: 0.5. The value of ΔR, which is the expected score minus the result (in the case of a draw, 0.5) is therefore 0.5-0.5=0, i.e. no change in rating.
  
  If instead their difference were 4 points rather than 3 (meaning that Carlsen's expected score would be 0.51 instead of 0.5), a draw would mean that his ΔR would be -0.01. With a K value of 10 (as he has a rating above 2400), his gain/loss would therefore be -0.01\*10. In other words, a draw with a rating difference of 4 would mean that he would lose 0.1 rating point (whereas Caruana would gain 0.1 point).
  
  > **Comments:**
  > **username_4**: If the ratings weren't that close, would they have changed already, or do they wait until the match is over?  
  > **username_3**: Officially, it's neither, as FIDE only updates their ratings once a month (per their official rules). However, it is possible to calculate real-time ratings after each individual game, as in done by [this site](https://2700chess.com/) for example.  
  
  ---
  
  ### Answer by username_2 on 2018-12-19. Score: 1
  
  FIDE apply a monthly update of rating but, during matches or tournaments, the ratings of participants it remains unchanged until the event is completed.
  
  
  ---
  
  