Recently, I'm interested in the rating distribution and I searched this.
Method of searching
- Searching the place of people (in active users) who has rating 999, 1049, 1099, 1149, 1199,... , 3049, 3099.
- Let pn be the place of people who has rating n.
- The number of people in range [1000, 1050) is p999 — p1049, the number of people in range [1050, 1100) is p1049 — p1099, ...
However, there was some surprising thing about it.
Look at following graph:
- The number of people who have rating [1900, 1950) is especially larger than [1800, 1850), [1850, 1900). ( twice larger approximate )
- The initial rating is 1500, but rating [1350, 1400) is about twice larger than rating [1450, 1500).
- The average rating is about 1450. This is lower than the initial rating: 1500.
Why these things can be occur?
UPD: The graph was extended.
UPD2: The average rating was calculated.
UPD3: The distribution and searchings about codeforces contribution is Here.