I just saw vanhanh.pham in top 5 of round 271 and remembered that he won another Div 2 round in the past. Then I found his performances quite "interesting". You may want to check his submissions in Div 1 rounds.
Although it is completely legal to do this, intentionally (I really hope that someone can prove me wrong) dropping rating to participate in Div 2 rounds officially is such a shameful behavior. I'm pretty sure I know his real handle and he has no trouble with staying in Div 1 (became red). How does he not know about unofficial participation in Div 2 rounds? * sarcasm *
I believe he will find it boring soon)
some people read tags flashmt. Some people do.
It's much more interesting to compete in Div 2 rounds officially, because you get placed in a room with div 2 coders and there more possibilities to hack solutions. worse, who used to intentionally drop ratings, however, gets praised by CF community.
worse just has fun with his own purpose. On the other side, this guy's actions are more like a kind of rating stealing from Div 2 users.
Stealing? It doesn't improve his rating any way. I'd like even to see a mathematical proof his actions have any long lasting effect on div2 coders.
He's taking the rating from Div.2 and gives it for free in Div.1. The fact that he doesn't leave anything to himself doesn't mean that he does not steal in the first place.
He takes, he gives blah blah, I am not convinced
This, kids, is why you can never win an argument with a stupid person.
what about coders who naturally fluctuate between div1 and div2? do they also take from div2 and give in div1?
Yes, but they aren't deliberately being assholes. He is, and you are as well.
Why don't you come with a mathematical proof that such actions generate long lasting impact on div 2 users? Because that's difficult unlike calling people you don't like bad names?
Do you know formulas of rating calculation? Because i don't.
And without these formulas it is hard to say anything about correctness of your claim.
I don't know the formulas, that's true. But we know it's similar to ELO, so there are some basic laws of this rating system. Let's take chess example. Let's say there are three people in the rating — you, me and my friend. Me and you are of similar level, my friend is of some arbitrary level. And let's say you never play with my friend, you play only with me and I play with him. In this case if we play fairly I think you will agree that all three ratings will show some good estimate of our relative skill even though you never play with my friend. But if we start playing dirty — for example I give up all the games to my friend, then rating becomes crazy, me and you will still have more or less similar rating but my friend's rating will grow. I think more or less similar things might be happening with CF rating.
Anyway, I don't think this rating stealing thing is worth worrying about — we have too many people in both Divisions and some people go back and forth, both of these facts mitigate that influence, so we probably won't be able to notice it.
But there is another thing here, he doesn't only steal rating, [assuming his "real" rating is higher than blue] he's also stealing victories from those who naturally belong to Div. 2. I think those victories matter a lot to Div. 2 participants and it's not fair to steal it from them if your level is higher, you have out-of-competition participation for that. In this sense I think his behaviour is similar to those who register new account just to win one round.
And one more example: consider Mohammed Ali on the top of his career participating in some local amateur boxing tournament. Just because he likes winning. And yeah, in order to increase his chances he will register in the fly weight category.
Thanks for response. Yes, I agree with your logic, and it seems intuitively clear and correct for me.
But my point is that we have a lot of people here who migrate between divisions back and forth unintentionally, and also lot of div1 users who participate in div2 contests from fake accounts for some reasons, and it does not creates "rating stealing problem" right now (or it does?.. maybe it is balanced by newcomers, who are giving their rating to div2? i have no idea), so there should be some mechanisms of preventing it, and it won't make a problem unless there are hundreds of very skilled contestants doing such stuff every round.
And i also wonder why CF don't publish rating formulas:) Waiting for it for a years:)
I strongly believe that the rating system has been heavily affected by people who use multiple accounts and there is no way we can prevent it.
The "rating stealing problem" is quite technical and I agree that it doesn't cause too much damage here. It is more of a moral issue that I want to mention in this post. There are reasons why we have 2 divisions. Just as what marat.snowbear wrote above, it is such a poor attitude to do whatever you want without considering the unfairness it will bring for others.
You believe.... Russell's teapot?
here is a blog by MikeMirzayanov about codeforces rating(Codeforces Rating System)
As i am a pure Div — 2 coder i am totally agree with marat.snowbear Thus lots of div — 2 coder like me lose the chance to go div — 1 and compete with best . Same thing goes to unrated Div — 1 coder also . Fun is good but it isn't good to steal other people opportunity also . please think about it all div — 1 coders .
Blog of MikeMirzayanov does not provides formulas. It just says that formulas are "ELO based". But formulas of rating calculation are not provided (compare that blog with TopCoder rating system description and feel the difference). Why did worse got only +319 in his last contest while some users with better rating and worse place got better improvement? Why can't we get -200 in single round while it is possible to get +200? It is just some "magic", i can't find description of it anywhere in that blog.
BTW, if it is true and you can't make a div1 now because of such "intentional cheaters" — there is also something good in it. When you'll finally make div1 again — it will be much easier for you to remain there, because you'll have much higher level:)
shakil_AUST has made it 2 times to div1, and each time fell back to div2 in the next match, then he complains here. BRILLIANT!
I have already completed my 105 rated contest among them only 2 of them as a div 1 participant . I know level of mine yet not stable to be a div 1 regular contestant and I am right now working on it . I ain't complaining about myself . I am talking about those who return back from 1680+ and yet not able to achieve the 1700+ mark . i believe sometimes little bit achievement work as an inspiration to do much better in future . Every div — 2 contest there are almost 15/20 div 1 contestant cut down the opportunity of those people . its not fear for those .
how do you define 'cut opportunities' and where's 15-20 figure is from?
beatoriche when you already a red/im/master coder , only for fun you open a unrated id to compete div 2 contest . i am try to pointing on those . if you look around you will see few of them in every single contest. Even lots of people maintain multiple account.what ever i think Leborn is right in his point .As i have to compete with them in div 1 why not here in div 2 . it surely increase my level .
its kind of true that easy gain isn't good for anyone , so how much coder like me suffer to achieve it , it will much more sustain . to be honest what ever be a div 1 contestant or not its not matter to me as long as i am able to participate and learning new things in every contest :D thank you so much for your wish , you are an inspiration for many of us.
Do you run out of problems to solve in div2? Well, tourist solves them in about a half of hour, do you?
So give his name to CF_Police_OnlyTrue :D .After any div2 (only) contest,there would be many unrated guys which finish in top 20.of course,many of them are other accounts of div1 contestants.This thing make it harder to rich div1 for real div2 contestants.someone should stop them.
Reaching div1 won't help you in life! Believe me, I was there :D
It is not so interesting to be in Div1. Number of rated contests is 2 times less.
Just enjoy your being in Div2! :D
Being a div1 contestant also have advantages — you can participate in div2 rounds without a risk to lose rating:)
Who cares I wonder?