KGS ranking revisited

[speedchase]

Then wouldn't you have to wait until it actually trickled down?

[wms]

Is there a reason not to anchor the strongest players at 9d and let it trickle down?

Yes, a very strong one. That means that as the strogest player rank changes, everybody shifts by the same amount. When the strongest player stops playing, if the 2nd strogest player is 2 stones weaker, then suddenly everybody jumps two stones.

Our current system sometimes has some changes when anchors are adjusted, but overall it is far more stable than anything based on a single player would be.

[snorri]

I'm not really fond of the stochastic walk ratings seem to take on KGS even when you don't play and I certainly don't like the expiration to '?' when you don't play for a while, but overall it may be the most accurate system in current use for players who play there regularly.

Other servers have had resets. IGS did some years ago (and I mean before the 2005 change, somewhere in the summer of 2002 when there was a 3-stone shift. I wasn't playing then so I don't know for sure. I guess right before than an IGS 1d was pretty darn kickass relatively speaking.)

If I wanted to get attached to a number, I'd buy a certificate.

[hyperpape]

Pippen: my point was that if that's what you want, you can't complain about KGS, since it's just one rating system among many.

Aligning all the ratings systems would require collaboration from around the world, and would also happen to be impossible at the present time.

[jts]

I'm not really fond of the stochastic walk ratings seem to take on KGS even when you don't play ...

It's not really stochastic, is it? It assumes that you would be able to beat the same people you were able to beat when you were last playing.

[Ortho]

.

[daal]

I'm not really fond of the stochastic walk ratings seem to take on KGS even when you don't play ...

It's not really stochastic, is it? It assumes that you would be able to beat the same people you were able to beat when you were last playing.

Yes, it assumes that while you were gone that you've been playing on Tygem.

[jts]

I'm not really fond of the stochastic walk ratings seem to take on KGS even when you don't play ...

It's not really stochastic, is it? It assumes that you would be able to beat the same people you were able to beat when you were last playing.

Yes, it assumes that while you were gone that you've been playing on Tygem.

Well, not necessarily. If your most recent partners decline, you'll decline to. It just assumes that, in the absence of evidence, you can still beat the same people and lose to the same people.

[witwit]

The amount of importance some people are placing on ranks in this thread is quite silly. The most important thing for a ranking system is to be internally consistent, ie trying to have differences in rank equate to 50/50 games with the appropriate number of handicap stones. Why does it matter if there is a "shift" in rankings and some bits associated with your account on a remote server change from 5k to 7k? All that matters is your actual strength which can never be characterized by a single number but by comparison.

[RobertJasiek]

The most important thing for a ranking system is to be internally consistent

A system with sudden shifts IS inconsistent.

[hyperpape]

Robert, like it or not, he's arguing about a reasonably well-defined concept. The fact that you don't like using the word "consistent" in naming that concept (which could naturally be named "momentary internal consistency") is pretty much irrelevant.

[RobertJasiek]

One should not call an inconsistent system consistent.

[daal]

The most important thing for a ranking system is to be internally consistent

A system with sudden shifts IS inconsistent.

But he said internally consistent. If everyones rank is affected in the same way by the recalibration, the system will be just as good at predicting an even match as it was before.

[RobertJasiek]

A rating system moving too many players upwards is internally inconsistent because a rating system shall be able to distinguish players instead of creating heaps of fake strong subpopulations.

[SpongeBob]

... heaps of fake strong subpopulations.

That sounds scary ...