After rounds problems appear in the problemset and somehow get their difficulties after some time. How is the difficulty selected for a problem and what's the time needed for rating to be determined?
| # | User | Rating |
|---|---|---|
| 1 | Benq | 3792 |
| 2 | VivaciousAubergine | 3647 |
| 3 | Kevin114514 | 3611 |
| 4 | jiangly | 3583 |
| 5 | strapple | 3515 |
| 6 | tourist | 3470 |
| 7 | Radewoosh | 3415 |
| 8 | Um_nik | 3376 |
| 9 | maroonrk | 3361 |
| 10 | XVIII | 3345 |
| # | User | Contrib. |
|---|---|---|
| 1 | Qingyu | 162 |
| 2 | adamant | 148 |
| 3 | Um_nik | 146 |
| 4 | Dominater069 | 143 |
| 5 | errorgorn | 141 |
| 6 | cry | 138 |
| 7 | Proof_by_QED | 136 |
| 8 | YuukiS | 135 |
| 9 | chromate00 | 134 |
| 10 | soullless | 133 |
After rounds problems appear in the problemset and somehow get their difficulties after some time. How is the difficulty selected for a problem and what's the time needed for rating to be determined?
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I read a blog from mike, they are automatic(obviously not manual), depends on the number of solves by rating groups, he fitted a curve or something for it, there is a old blog for it. I think it takes a few days for ratings to come
It is calculate though the number of solves. If very few people solved a problem, it will receive high rating, and vice versa. Due to this, sometimes problems are severely overrated or underrated. I have seen some 1400 problems that feels like they should be 1800, and 1800 problems that feels like they are 1200.