Bug in Rating Change

I was penalised with rating deduction for plagiarism and ended up with 0 rating.

I scored 530 points and was at 0 rating, people with a 1000+ rating and 500 points in MAY18 got more rating increment than me.

@vijju123 @admin

Please give me some profiles for reference


This might be due to volatility factor as mentioned in codechef rating mechanism.

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Yes, this situation can happen due to volatility factors. We will max out (i.e. keep it 200) the volatility factors for people with zero ratings to avoid this scenario. Thanks for notifying.

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Compilation of Plagiarism Concerns

Yaa, in the given link they have said about volatility factor, it will calculate how well users are performing w.r.t. their rating. But they also said that it will allow a fast recovery of rating if you stick to your old account which didnt happen so.

But they also said that it will allow a fast recovery of rating if you stick to your old account which didnt happen so.

Which is addressed in the answer just above yours by @dpraveen . Your point?

So, will the rating update?

The problem is not with the volatility.
The rating changes are capped with a max rating change computed as 100 + (75/timesPlayed+1) + 100*500/(|R-1500|+500). If it is your 3rd contest and you have been plagiarised 2 times, then also your rating change by at most 150. And this is the worst case. In an average case, it is increasing by around 128-130. Maximum rating change capped needs to be increased for such users to regain their ratings instead of volatility factor.


still, the rating bug is there in may cook-off

How long will it take for rating to get updated?

Still, no steps have been taken by your side. In yesterday’s lunchtime, the users with a higher rating than me, and worse rank in the contest were awarded an increment of 192. I was still bottled on +132.

If it keeps going this way, I will never get my ratings back despite performing better than others who are getting rating rise insanely.

Codechef is best at procrastinating and not replying.

They are slow, yes, but its not something I can expect them to sort out in this much time. I will talk with them again.

@rohitthapliyal I have talked with CodeChef about this and their reply was “We don’t want to make changes in our rating system for the cheaters. Also, this is not what we are focusing on right now. We have many things in our mind and this is not one of them”. Now, I was too penalized for plagiarism but I completely accept my mistake. I would advice you to keep participating in contests without worrying about ratings, the main objective here is to learn. No one cares what ratings you have. If you are too concerned with ratings then go to codeforces and start improving your ratings there. Colors don’t change much on codeforces hence you won’t be complaining about that.

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