Radin_Zahedi's blog

By Radin_Zahedi, history, 3 months ago, In English

I believe there's a bug in CodeForces ratings, because when ratings are rolled back, my previous contest rating is increased by 2, and it's now the second time it happens. What is the cause?

 
 
 
 
  • Vote: I like it
  • +11
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3 months ago, # |
  Vote: I like it +40 Vote: I do not like it

Maybe cheaters were disqualified and your ratings increased.

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3 months ago, # |
  Vote: I like it +17 Vote: I do not like it

I guess the ratings are rolled back when some solutions get plag and contest get skipped for some participants and if they were better in rating than you then your rating improves .So, when they are awarded back delta might increase.

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3 months ago, # |
  Vote: I like it +45 Vote: I do not like it

That's the whole point of rolling back ratings

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3 months ago, # |
Rev. 2   Vote: I like it +11 Vote: I do not like it

I remember Mike writing somewhere that ratings are rolled back when he is removing people for cheating. Ratings were prematurely updated so that people can participate in the upcoming contests otherwise people who became CM from expert in the last Div 2 will lose rating after participating in an educational round. So to prevent from this, ratings are updated and then later rolled back to remove cheaters.

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2 months ago, # |
  Vote: I like it +5 Vote: I do not like it

Hello dear Radin !

Roll back of the ratings is for identifying the cheaters, and after identifying the cheaters, they will be removed from the competition and your rank will improve and you will get more ratings. I hope it was useful!

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2 months ago, # |
Rev. 4   Vote: I like it +3 Vote: I do not like it

The cheaters were moved and then your ratings increased :)
btw, the rating of one of my friend shygo_cmll01 decreased by 1 when ratings are rolled back. I just want to ask for the reason because he says that he didn't do something wrong before rolling back.

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    2 months ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    I'm here qaq

    I checked it again, and I'm sure that my score is still 2360 now, but my rating decreased:(

    +550 -> +549