30k? to 2d? by not playing for a few months?

[RobertJasiek]

The statistics provided by you refer to the recent changes between 5d/4d/5d while my earlier statements referred mainly to those rank changes in earlier years. The recent 4d/5d change was not typical for my experience in particular because I played relatively few games per day on average as a 4d during that recent period.

Your argument considering "25 losses to demote, and hundreds of wins to promote" as absurd presumes the rating system to be ok and that the earlier games before a rank drop should make it more difficult to increase in rank. - Contrarily I think that it should be equally easy to drop and increase and that therefore a rating system must not, apart from the current rating, still reevaluate old games at all. - The required extra effort for frequently playing players is also bad.

[Uberdude]

About the original 2d? question, just to reiterate: it is a bug, my Uberdude kgs account is currently showing it and started to do so when my last ranked game 6 months ago dropped off my record.

[palapiku]

I haven't played for a while and now both my accounts are at 2d?.
For the first time ever, my kibitz is taken seriously...

[bearzbear]

Solution?

Simple, play elsewhere if you care about this sort of thing.
Play on the server in question for fun.

Imo, while the server has seemed to be bringing higher quality players aboard in recent time, in my view it is the "AOL" of servers...

Rank and rating are really unimportant in the larger scope of things.
Suggest trying to enjoy the act of playing, and forget about "winning"
or where your rating happens to be?

After all, everyone except for a handful of top pros are weak and puny, so
why pretend otherwise?

_-_-bearzbear

[Mivo]

Solution? Simple, play elsewhere if you care about this sort of thing.

That is a silly suggestion. KGS is "the" Go server for the English speaking community, and wishing for a reliable, consistent rating system isn't an unreasonable desire.

[shapenaji]

Solution? Simple, play elsewhere if you care about this sort of thing.

That is a silly suggestion. KGS is "the" Go server for the English speaking community, and wishing for a reliable, consistent rating system isn't an unreasonable desire.

Agreed, but that being said, this is why I play on WBaduk or Tygem now. With my winning and losing streaks, a reasonable rating system should have had me falling down a rank and jumping up a rank. Winning 11 games in a row over a month, and losing 11 games in a month does not suggest that I have the appropriate rank. It suggests that I was playing at 5d during one month, and then at 3d at another month.

Tygem's system is elegant, I wish KGS's were more like that. KGS's system never rewards you or punishes you. Tygem tells you exactly what you have to do to jump up a rank, 2 ranks, or if you're in danger of falling down 1 or 2 ranks.

For every 20 games, it looks at your percentage and then decides whether to promote or demote.

KGS seems to be designed with the belief that somehow the last 180 games should be consistent with a single rating, which makes no sense to me.

[Mef]

KGS is "the" Go server for the English speaking community, and wishing for a reliable, consistent rating system isn't an unreasonable desire.

With my winning and losing streaks, a reasonable rating system should have had me falling down a rank and jumping up a rank. Winning 11 games in a row over a month, and losing 11 games in a month does not suggest that I have the appropriate rank. It suggests that I was playing at 5d during one month, and then at 3d at another month.

Unfortunately these two desires are in conflict. Human perception of what is reasonable with respect to how they should be ranked is not typically reliable and consistent (or at least, it's not reliable and consistent to the end of giving a good game. Many people will reliably consider themselves over-ranked or under-ranked). If your desire is to play games where you have a 50% chance of winning (i.e. properly handicapped), it is better to use a system you may not find intuitive. You can provide the fluidity users desire, however you must sacrifice some of the consistency and reliability of the rating system.

Remi Coulom actually looked at even-handicapped KGS games as sample data for evaluating rating systems. Over a period of two years the KGS rating system correctly predicted the game outcome more often than an Elo or Glicko system. A simple "Win X then promote, lose X then demote" would fare even worse in this respect (there was an algorithm that fared better than KGS, however it would be even more involved mathematically, and even less intuitive for the participant).

Of course all this falls outside the initial [2d?] issue, which an easily be resolved by playing a single rated game. None of the people affected by the [2d?] bug are actually involved in any ratings calculations (as they have no rated games in the previous 180 days)

[shapenaji]

Remi Coulom actually looked at even-handicapped KGS games as sample data for evaluating rating systems. Over a period of two years the KGS rating system correctly predicted the game outcome more often than an Elo or Glicko system. A simple "Win X then promote, lose X then demote" would fare even worse in this respect (there was an algorithm that fared better than KGS, however it would be even more involved mathematically, and even less intuitive for the participant).

I'm confused, if they were even-handicapped, how would any rating system fare better than 50%?

That tells me that KGS trusts its range inside of a rank, but it does not tell me that the players within that rank are less than a stone apart...

In fact, if anything, that tells me that there is more than a stone difference inside a single KGS rank, since otherwise, the results would be extremely uncertain.

[quantumf]

Some anecdotal evidence regarding Tygem...

I tend to prefer playing on Tygem, partly because the games tend to be more entertaining, partly because I'm not as invested in my rank, partly because of the more fluid rating system. HOWEVER, I must acknowledge, in line with recent comments from mef, that the quality of my opponents if very divergent. I'm rated 2d on Tygem (and 1k on KGS), but I often feel I am playing against players 5 stones weaker or stronger than me. I tend to dominate or be dominated. In contrast, on KGS, my games tend to be close, and I very rarely feel that I'm playing someone inappropriate.

[Mef]

I'm confused, if they were even-handicapped, how would any rating system fare better than 50%?

That tells me that KGS trusts its range inside of a rank, but it does not tell me that the players within that rank are less than a stone apart...

In fact, if anything, that tells me that there is more than a stone difference inside a single KGS rank, since otherwise, the results would be extremely uncertain.

Ratings have much finer precision than a single stone. A strong 1D (borderline promotion) vs. a weak 1D (borderline demotion) have essentially a full stone difference in strength between them, even though they play even (so the expected winrate is closer to 75-80% for the stronger player). As such, you would expect to be able to predict better than 50% of the games. Also worth noting -- the systems were trained with 5 years worth of KGS game data prior to the 2 year period analyzed -- so if a rating system did a better job of ranking these players, it would be able to pick out the games that were mismatches (because one player was ranked incorrectly, and the handicap isn't properly set by its own rating) and improve it's predictions even more so.


Edit/Addition: Also worth noting in this case to address your concern, the correct prediction rates were on the order of 54-57% , so it is still close to 50/50...it's just that some systems will correctly predict thousands more games/yr than others

[blade90]

I agree with shapenaji, the only bad thing about the KGS rating system is:
When I started to play on KGS winning 1 game was enough to go up a rank or more, this is considered normal until the rating system adjusted my "real" rank (without the ?).

But the more games I play the harder it becomes to change my rank.
In this month I reached 4k with a score of 18 wins and 12 losses (as 5k) with a winning streak of 11 wins (after the 7th win I was promoted), this sill seems normal because I played 20 games as 5k and won 60% of them.
But as 4k it is a bit confusing, my 4k game count is 9 wins and 2 losses that is about 80% after 11 games, after looking at my rating graph I need about 4 more wins to get promoted - if I can miraculously win the next 4 games without losing (~85%). 1 loss more means 1 win more, and here is the problem - not counting to losses I need now 11 wins to get promoted while as 5k it only took me 6 wins. I am willing to play and win/lose until I reach 20 games but I don't think this helps.
If it is going to be like this, then it would make more sense to use the tygem system, or to set a new rank every 20 games and if the win % is between 45% and 55% you can keep the rank. Something like that make more sense. Also another bad thing about the KGS rating system is when you played about 30 games and then don't play for about 4 weeks your rating changes by 3-5 stones! This is something I experienced when I started to play go.

Also there was a certain KGS 3d (don't remeber his name) who was inulted by other 3d's to be a sandbagger, he by the way played about 1000 games in the last months and he already won about 20 games, no losses but in his rating graph it moved only 1/4 stones up. Remember he has a 20 games 100% win rate as 3d but he need to win 60 more games to get promoted! He could make a new account but te same thing will happen again.

Well I can understand if KGS wants to keep it's rating system but it should only take the last 50 or 100 games into the calculations and not 6 months, which could be 1000 games! But that is ust my personal opinion, I do hope it is getting some adjustments.

[shapenaji]

See Mef, I see a problem with the idea that over time you will be able to lock on to a person's rank. I think that's only true if a person's growth is stymied. There are a lot of people who have hit a barrier. Statistically speaking, probably 90%+ of games played are played while at a barrier of some kind or other. (Simply because you spend a good deal more time at them, that's why they're barriers)

KGS may have an extremely accurate rating system by tracking a user over a long period of time. But, to me, that's like saying "Well, it's rained the last 3 months here in Oregon, therefore, by induction, it will be raining in July"

That system will be:

A) Frustrating, since it will not adapt quickly when a person breaks past that barrier
B) Capable of impeding growth, since if a person DOES start to do better, and gets no new challenges, they can fall back into their old barriers. In this way, it ends up enforcing its own ranks.

There is also serious evidence of a problem when players realize that these are issues, and do what has now become the norm, when you get stronger, you make a new account.

No one wants to lift the load of 180 days of previous games, especially when they're advancing. Why should they need 20 or so games just to get to the next rank? Why should they quit playing on KGS for a while just so that they have less inertia on their account? Why enforce this when people bypass it anyway?

[oren]

The funny thing is that I have the opposite problem. I play few enough games online that I can move my KGS rank quickly, but there's no way I can move my Tygem rank much at all.

[hyperpape]

There is also serious evidence of a problem when players realize that these are issues, and do what has now become the norm, when you get stronger when you want a higher rank, you make a new account.

Bear in mind that there is a lot of wishful thinking going on. If you have a group of people who all mistakenly believe that they're stronger than they are and create new accounts, a substantial fraction of them will end up with a higher rank, at least for a good long while.

But all this has me wondering if it's possible to create a system that is somehow intermediate between counting all games from the past 180 days and one that only counts the most recent n games?

Imagine that over the last 180 days, I have played either 20 or 1000 games on KGS. In the first case, the system has no idea how much time I'm spending on go. In the later, it knows that I'm spending lots of time. So it should think the probability that my strength is going up is higher, without looking at the results of the games. Could it therefore count the more recent games more heavily in the later case? Has this ever been tested?

I know that 179 day old games already count less--what I'm proposing is that for two players, one of whom is playing more on the server, their older games count even less.

[speedchase]

I know that 179 day old games already count less--what I'm proposing is that for two players, one of whom is playing more on the server, their older games count even less.

I believe (however I am not certain) that WMS has stated that there is a halflife of 45 games.