Question About Rating Predictor

This is about Long Challenge. Suppose there are two person A and B. Now A has an initial rating of X and B has an initial rating of Y . If they score exactly the same in any long challenge . What would be the effect of their final ratings? I thought it would be same? but the codechef predictor shows different rating prediction for two such person. It says person whose username comes first in dictionary order will get higher final ratings…Is it the case? If Yes can is there a way i can change my username to something like “aaabbb”? lol :laughing:

Not like that. Supoose my rating is 1799. And i solve 1 questions, then my rating will decrease… Because as per my current rating, i am supposed to solve more than one… But if my rating is 0 and I solve 1, solving 1 is much greater than what I am expected to solve. So rating will increase … Actually there is a formula that calculates your predicted rank based on your and all other users performance, if you rank better than your predicted rank, rating will increase… Decrease otherwise.

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yeah but say two people have same initial rating. They perform equally in LONG Challenge, where ties are not broken. What would be the outcome then? :thinking:

If they have same rating initially, they will share same rating afterwards if they score same.

Yup thats what i think but according to Codechef Rating Predictor https://ccrate.github.io/ two guys having same rank (same score) and “Same Initial Rating” have different final ratings in Long Challenge :slightly_frowning_face:

Can you share those profiles

The rating calculator has other parameters too like number of contest participated by the contestent and variance factor.

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https://privnote.com/yNeRXWAa#Daj92Gj6X

First, I’m amazed how you were able to find a profile of someone who has same contest rank, same global and country rank as you.
Second, both profiles are not exactly similar. You have only participated in 3-4 contests while the other person has been a part of more than 20 contests with lots of ups and downs in their rank. Also, even if the global and country ranks are similar, the individual ratings for long, cook-off and lunch challenges differ for both profiles. This might be a good reason why changes in rating are different, but I’m pretty sure that your username has nothing to do with it.
Maybe if both your Long Contest ratings were same, same rank in a Long contest would’ve resulted in same increase in your ratings.

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@rude009
Haha we share same college, i could see it in leaderboards I’m a Junior, was hoping to surpass this contest but will have to wait till next contest. Btw thanks for clarification. :smile:

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So the one who has participated in less competitions will have high rating uplift ( if other parameters are constant ? )

No, it’s the opposite. I participated less so i am getting less increase in rating even though everything is same

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This judging system should be clear enough for newbees to understand .

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Most likely as in the elo+ function there is a reciprocal of number of contest participated. Check Rating Mechanism | CodeChef

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