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sslotin's blog

By sslotin, history, 20 months ago, In English,

So, I scraped stats.ioinformatics.org for some data to estimate the correlation between CF rating and place you get at IOI. I guess many will find these plots interesting.

I only considered contestants who had  ≥ 5 rated contests during last 2 years before 1st of August of the relevant year. Years 2013-2017 had more than 120 such contestants, but IOI '12 had only 55 and earlier IOIs had even less, so I didn't go any further.

By "normalized # of inversions" I mean this: , i. e. actual number of inversions divided by maximum possible. This is some kind of measure of a contest being close to a standard CF round.

For more details, check out the code: https://gist.github.com/sslotin/ae9557f68bb7e7aea1d565e2229a81c9

 
 
 
 
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20 months ago, # |
  Vote: I like it -59 Vote: I do not like it

it is uninteresting

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20 months ago, # |
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It's interesting how the points are scattered in the graph from 2017. I think it's because of that problem.

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

Wew. The same rank at IOI has rating spread around 750, which is about 3-4 different titles/colours. That's comparable to σ of CF rating distribution (I'll ballpark it at 300).

We can see from the graphs that the average CF user (rating 1500) has a decent shot at anything from bronze to nothing and a barely div1 contestant (rating 1900) has a shot at anything from gold to nothing.

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20 months ago, # |
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p-value?