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?
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 | tourist | 3892 |
| 2 | jiangly | 3797 |
| 3 | orzdevinwang | 3706 |
| 4 | jqdai0815 | 3682 |
| 5 | ksun48 | 3588 |
| 6 | ecnerwala | 3557 |
| 7 | Ormlis | 3532 |
| 8 | Benq | 3468 |
| 9 | Radewoosh | 3463 |
| 10 | Um_nik | 3450 |
| # | User | Contrib. |
|---|---|---|
| 1 | cry | 165 |
| 2 | Qingyu | 159 |
| 3 | -is-this-fft- | 158 |
| 3 | atcoder_official | 158 |
| 5 | Dominater069 | 156 |
| 6 | adamant | 154 |
| 7 | djm03178 | 151 |
| 8 | luogu_official | 150 |
| 9 | awoo | 148 |
| 10 | maomao90 | 145 |
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.