but it can be tested and actual comparisons made.

perhaps you'd like to read Remi Coulom's paper
http://remi.coulom.free.fr/WHR/

I'm not sure if that deserves a response, but the unpredictability of Tygem ranks is primarily due to sandbaggers and the fact that you can register anywhere from 18k to 5d.

If you feel that the Tygem ranks are unpredictable, and if you feel that they do not adequately suit you with a proper opponent, then it is indeed an indication that the ranking system does not fulfill its purpose from your perspective. As I stated in the earlier post, there is no perfect ranking system, and they all have at least some set of assumptions and model upon which the ranking system is based. I also stated that the only real measure you can have of the system is how well you feel that the rank pairs you up appropriately with opponents. Precise measurements are only from the context of a given model with some set of assumptions.

And I do not intend to use "statistical inference" to mean whatever I want. I have provided what I hoped would be an objective definition - I selected it from Wikipedia, but I'd be open to using other sources.

I've also indicated examples, such as in natural language processing, where simple measures of statistics are used. Taking the average word count for a given word from a set of text, for example, seems like a simple and basic measurement to use for predicting the likelihood of a given word in new text, but it's still used, and it's still a statistic.

I have done my best to give an objective definition of statistical inference, and I'm pointing out that this definition can meet a wide variety of cases, whether the analysis be simple or complex. Based on your responses, it appears that you prefer the KGS ranking system to Tygem's. Perhaps you feel that when you play on KGS, you are more consistently paired against opponents that are close to your skill-level. This is perfectly fine, and it's a fair opinion to have.

But to say that KGS's system is "statistical" and that Tygem's is not is not a fair statement based on the definition of statistical inference that I've posted, and you have not indicated an objective reason to the contrary.

Please do not accuse me of defining "statistical inference" to mean whatever I want, as I have tried my best to give an objective definition. And between the two of us, I don't think that I am the one that has failed to provide a definition statistical inference from an external source.

Maybe you don't like Wikipedia's definition. Then, please link us to another one. Perhaps we can find a definition for which Tygem's ranking system is not "statistical".

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be immersed

Certainly, I absolutely agree, and I actually have read the paper in the past. From the paper:



In a more general sense, ranking systems can be evaluated based on their accuracy given an objective sample set of data. On a personal level, this corresponds to my earlier explanation of how I feel a ranking system should be tested - if you feel that the system suits you up with appropriate opponents, then that's what matters.

This could be done based on your own feeling, or you could take a more systematic approach. For example, you could play 100 games on Tygem and 100 games on KGS, and then compare your win rate to the rank that you're given by the ranking system. You could analyze this in a number of ways.

But for better or for worse, empirical results are the indicator here, and not the idea that "this system is more statistical than another system".

And I personally believe that it's possible that if you and I were to both do an empirical analysis to determine the best ranking system, we could achieve different results based on the sample data we have (eg. from the games we each play). For example, I might have the bad luck of playing against a sandbagger on KGS and you might have the bad luck of playing against a sandbagger on Tygem.

In any case, I totally agree. We can make attempts to compare the systems based on sample data, but those attempts will still be subject to what we're measuring in the study, the data we sample from, etc. And the KGS ranking system certainly isn't better than Tygem simply for being "more statistical".

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be immersed

Just to get back to the question...

There is definitely a stylistic difference between the two servers. Fights that involve enormous groups are common on Tygem, rare on KGS. For me anyway. I'm 6k on KGS and hovering between 8 and 9k on Tygem. I have recently started winning more games on KGS, directly as a result of playing more on Tygem I think. Playing on the 2 servers also allows me to reduce playing on KGS, which means my rank is more sensitive to results.

Probably your'e still in sandbagg zone.

Register as a 1d on tygem, you'll be able to beat about 50%
I'm a 3k on kgs and 1d on tygem and mostly I'm able to keep my rank.

Edit: I do play on the chinese servers, not sure if that makes any difference.

Cheers,
Otenki

Posts like this make me wish for a thumbs down vote. Obnoxious on several levels.

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- Brady
Want to see videos of low-dan mistakes and what to learn from them? Brady's Blunders

What's the best thing you can say about a statistical analysis?

Yes. Six years ago i was 7 kyu on kgs with ease, but couldnt get above 22 kyu on wbaduk. Was somewhat disappointing. The reason I got better, was learning to punish their overplays right. Often by outright ignoring them or do some simple shape move he has to answer and takin sente.

I made the experience that on wbaduk the higher the rank the stronger the skill. I didnt lose against a 9k for a long time, and have never won against a 4k. So there must be some correlation. Its just there the rank has to be taken with a + or - 1 or 2. Except for the sandbaggers obviously. But often i cant really say if its an sandbagger or if i just play like junk.

On the gamestyle: I have the feeling on wbaduk it's more about reading than about opening and shape. Those guys raeally can't surrender, and you have to play all out and defend a 40 point margin against all their overplay attacks and really count well that semeai. As it's a bit humilating to just defend the safe way against overplays i play at the hard edge and so often lose won games. Maybe he just fills in the semeai at the end, that i think i win surely counting to 5 liberties, and only playing on the last possible moment. And then there is some neat shortage of liberties tesuji that i oversaw and gives him one liberty more and the tide turns 100 points. Sometimes i play safe, but like i said: I's boring.

I don't find many sandbaggers at the 10k level on tygem. Occasionally I play someone who appears to be miles ahead of me, but that happens on KGS as well. I chalk it up as a loss, review it, and try again. On the whole I appear to be evenly matched at this level, much to my continued frustration!

I seemed to level out at 10K on W Baduk. I seem to lose most of my games due to single large blunders that kill some of my stones during the endgame, but I nearly always come out of the middle game with a commanding lead. I think I am going to play mostly on Wbaduk for a while. Who knows, that might make my AGA/KGS rank go up a few stones too.

KGS compared to IGS ranks are pretty obviously inflated in some ranges. I haven't played on KGS for a while but when I did at 7kyu there were a several stone difference, maybe 4kyu. The style of play is also fairly narrow on KGS, probably since everyone studies the same books.

Tygem players also feel more sharp to me. If you don't pay attention or lose focus for a little bit, your game could get flipped. On Kgs, it feels like you can play more leisurely games more easily. Though I think this may be because if tygem players see something they think is a weakness, they will play it whether it is or not.

Not stepping into the arguments of this thread but just to add a response to the inital question:

Servers such as IGS and Tygem where you can put in your own rank will always feel a bit off. I know many KGS 1-4ds who start their rank at 12kyu on those servers and attempt to work up. At the same time I have recently learned of quite a few KGS players (most rangeing from 1kyu-9kyu) creating 5D accounts on tygem so they "can play stronger players and learn how to play" which in my opinion is a very wrong approach....but there is a 5D KGS player recommending it to them ashamed to say.

Also most westerners seem to have the perception that if their win/loss ratio is too bad... to just create another alias. Aside from that though I can say my Tygem accounts in the past have always been within 2 ranks of my KGS names. I feel Tygem deals with many more overplays but reasonable ones , while KGS seems to be filled with unreasonable overplays and players do not develop the proper way to handle them. Again this is based on my experiences and knowledge.

I have been trying this out recently. I have only played 5 games thus far on my 1 Dan Tygem account, but I am at 2 wins and 3 losses. Its a bit early to say that I am stable in my rank, but I also have not felt completely outclassed by any of my opponents. Its kind of crazy that I can have both a 9k account and a 1d account on the same server.

Well, the point jts was getting at is that Tygem's ranking system is a purely descriptive one, while KGS's rating system is a predictive one. Tygem's system is meant to do nothing other than describe what you have done in the past. If you see someone rated 9k, it is obvious how they got there (they won X number of games as an 10k, or lost X number of games as a 8k). It makes no attempt to predict what may happen in the future.

On KGS if you see someone rated 9k, it may be unclear why they are there (did they win games as a 10k? Did they have an opponent who did well after they played as 12ks? Have they even played X number of games at all like the guy from tygem?). The rank signifies what the server is predicting for how they will play in the future (they will have a 33 to 66 percent winrate against other 9ks).

Some people prefer a descriptive system, because they want a rank to reflect achievement (Professional ranks are like this. A professional rank makes no attempt at predicting who is supposed to win a matchup, instead it signifies the achievements of the owner). Others prefer a predictive system because they want a rank that provides a fair match up (that is, it predicts that these two players will play at a similar strength in the future). To each his or her own.

What you say as "purely descriptive", do you mean that the Tygem ranks does not tell the strength of a player? So that you don't know what will happen if a 5kyu and 5dan in Tygem matches up, and it's unable to predict who is more likely to win, because the Tygem system is "purely discriptive"?

Well, in my opinion, perhaps I've misunderstood your words, but I can't agree with you, and a 5dan does win a 5kyu in Tygem.

It is true though, the 18kyu in this server is somehow mysterious, and more likely to win a 5dan than the 5kyu.

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Wait, please.

I've understood that the KGS system takes into account your opponent's performance even after the match you had with him (up to how long I'm not sure). E.g. you're 10k and beat a 10k dude. Then this opponent goes on a win streak and becomes a 5dan. KGS keeps calculating your rating and sees that you beat a player who in reality is 5dan, and your rating will skyrocket as well. When you have lots of games this effect is of course not so dramatic and it can even be hard to go up a rank even if you keep winning.

Please correct me if I'm wrong, but this is how I remember it.

For stronger players, it just doesn't make sense that you would play a 10k who ranks up to a 5dan within the window of KGS ratings. Maybe from 25k to 10k, but there in lies the rub if as a 10k you play a bunch of handicap games as white, your rank will go up riding on the wins against double digit kyu who improve dramatically, but against even competitors, you lose.

I'm not sure if you mean that my example was quite extreme (which it is for the sake of demonstration) or the way KGS system works is. In any case, the above was just to show how KGS rating system also retroactively takes into account your past games / your opponents' future performance. Whether it's good or not is up to the player's opinion.

Personally I see KGS as waaaaay more stable in terms of rank accuracy (vs. WBaduk, Tygem) in the kyu range, and my understanding is that it mostly applies to dan ranks as well. The exception being what you pointed out, but I haven't seen that nearly as much a problem as truly random ranks elsewhere.