Ykd's blog

How does rating system work?
By Ykd, history, 4 months ago, In English

Hello World,

Something happened with my rating which I cannot understand. I gave a contest and my rating increased by +135 (1012 -> 1147). But in the next contest I performed poorly, and my rating decreased by -94 (1127 -> 1033). Yes, that's not a mistake, after giving the second contest, the rating change for previous contest changed to +115 (1012 -> 1127).

Can someone please explain why and how this happens?

What are the factors on which rating change for a contest is decided?

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4 months ago, # |
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Auto comment: topic has been updated by Ykd (previous revision, new revision, compare).

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4 months ago, # |
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If you are Chinese. You can see sister ruler's blog.

https://www.luogu.com.cn/blog/ak-ioi/cf-at-rating

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    4 months ago, # ^ |
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    Thanks. It explains rating system but not how one's "rating changes" for previous contests change after later contests.

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      4 months ago, # ^ |
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      Your later contests don't affect the rating changes of previous contests. But rating changes from contests can change afterwards. This is because when ratings are updated after each contest, the leaderboard might contain cheaters. Later the admins remove cheaters from leaderboards and recalculate old rating changes.

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        4 months ago, # ^ |
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        Thanks for clarification.

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