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gambitcrazy
25-01-2010, 05:00 PM
Has there been any discussion here about NZ's recent ratings jump? Since we don't have a chess forum of our own and most NZ players are on this forum here anyway...

http://www.newzealandchess.co.nz/downloads/ChangeInRating.doc

I got around 150 extra points despite not playing for several years... but when I was playing I did play all of the last bunch of upcoming juniors eg Daniel Shen, Michael Wu, etc, and beat quite a few of them (unlikely to be able to do that now!)

Adamski
25-01-2010, 05:14 PM
Has there been any discussion here about NZ's recent ratings jump? Since we don't have a chess forum of our own and most NZ players are on this forum here anyway...

http://www.newzealandchess.co.nz/downloads/ChangeInRating.doc

I got around 150 extra points despite not playing for several years... but when I was playing I did play all of the last bunch of upcoming juniors eg Daniel Shen, Michael Wu, etc, and beat quite a few of them (unlikely to be able to do that now!)Perhaps I should re-cross the Tasman in order to get back over the 1600 barrier! Only trouble is I would have to find a job...

Tony Dowden
29-01-2010, 08:06 PM
While a possible eye-brow raiser, the 'jump' was a sensible adjustment.

If pigs would fly we'd switch to Elo here in Australia and apply some 'jump' therapy - and I'd get a ratings reassessment on my games vs Morris, Illingworth, Naukachi, Yi, Schon, Dyer, etc :whistle:

Bill Gletsos
30-01-2010, 12:14 AM
While a possible eye-brow raiser, the 'jump' was a sensible adjustment.That puts NZ around 5 years behind the ACF in the use of "intermediate ratings".

If pigs would fly we'd switch to Elo here in Australia and apply some 'jump' therapy - and I'd get a ratings reassessment on my games vs Morris, Illingworth, Naukachi, Yi, Schon, Dyer, etc :whistle:You dont know what you are talking about.

The ACF Glicko system already uses "intermediate ratings" in its calculations for all players. All ratings from December 2000 to June 2004 were rerun to incorporate this change and the recalculated ratings using "intermediate ratings" first appeared in September 2004.
Also changes were made prior to the calculation of the December 2006 ratings and all ratings from December 2000 to September 2006 rerun to better handle improving players be they juniors or adults.

Testing showed that because of the unresponsive nature of Elo to junior improvement even with the use of intermediate ratings, juniors would have been more underrated under Elo and therefore adult players would still be worse off.

Brian_Jones
30-01-2010, 07:45 AM
That puts NZ around 5 years behind the ACF in the use of "intermediate ratings".

You are entitled to your opinion but this does not make it right. :evil:

Certainly the ACF is more advanced in the use of mystique (and bullshit?). :evil:

I prefer a rating system that is open and well-documented. maybe the ACF should go back to an open system?

Kevin Bonham
30-01-2010, 09:49 AM
You are entitled to your opinion but this does not make it right. :evil:

That probably applies much better to your comments. The introduction of intermediate ratings was widely canvassed on this forum in the "Planned Ratings Changes" thread in mid-2004, and then in the September 2004 thread it was noted that the system was in operation following a recalculation of all ratings. Thus Bill's comment that the ACF had already been doing this sort of thing around 5 years ago is not an opinion, let alone one that might not be right, but a matter of documented fact.

Adamski
30-01-2010, 10:03 AM
Can someone enlighten me as to what "intermediate" ratings means? Is it to do with being able to calculate a rating in the midst of an unfinished tournament?
Thanks.

Kevin Bonham
30-01-2010, 10:11 AM
Can someone enlighten me as to what "intermediate" ratings means? Is it to do with being able to calculate a rating in the midst of an unfinished tournament?

No, it's to do with taking into account the player's performance in the ratings period when deciding how to assess results scored against them. So for instance if you lose to someone rated 1400 but they actually played much stronger than that in the period and hence their rating goes up, you don't get as much damage as if you lose to someone who is a genuine run of the mill 1400.

Here is an example of how to do a simple version of intermediate ratings:

1. Calculate all the rating changes for a given period.

2. Add each player's suggested new rating after 1 to their old rating and divide by 2.

3. Recalculate all the rating changes for that period substituting the figures you got in step 2 for the ratings of each player's opponents.

4. Use the ratings obtained from 3 as the players' new ratings.

There are many different versions of this system.

The NZCF version says:


There are now four phases in the rating calculation. Phase 1 handles unrated and provisionally rated players while phase 2 handles established players. After phase 2, those players who have had an exceptional performance, a bonus point gain, get an intermediate rating that equals the pre-period rating plus basic rating points only. For other players, their intermediate rating is still their pre-period rating. Phases 3 and 4 are repeats of 1 and 2, this time using the intermediate ratings for a player’s opponents. For example, a player has a pre-period rating of 1639 and an intermediate rating is 1741. Using the intermediate rating, for an 1800 opponent, this means a 13% decrease in the expected score while for a 2000 opponent, an 8% decrease.

Adamski
30-01-2010, 10:30 AM
Many thanks, Kevin. I am probably not the only person who did not understand the concept. Now I do!

Kevin Bonham
30-01-2010, 10:47 AM
It's clear that the NZCF version is only a partial implementation of intermediate ratings, because only those players who perform well enough to get bonus points under ELO are assigned an intermediate rating. That said the intermediate rating they are assigned (their rating plus normal gain) is a reasonably strong one.

Tony Dowden
30-01-2010, 02:56 PM
You dont know what you are talking about.

:hand: Bill, my argument is perfectly valid. You are reframing my argument according to the Glicko context - meaning that you have a perception problem ...

Bill Gletsos
30-01-2010, 05:53 PM
:hand: Bill, my argument is perfectly valid.No it isnt.
Your argument is simply wrong.

You are reframing my argument according to the Glicko context - meaning that you have a perception problem ...The only one with a perception problem is you.
You were commenting on the NZ use of "intermediate ratings".
Glicko2 is superior to Glicko which is superior to Elo.
Glicko2 with "intermediate ratings" is superior to Glicko with "intermediate ratings" which is superior to Elo with "intermediate ratings".

Brian_Jones
31-01-2010, 08:07 AM
No it isnt.
Your argument is simply wrong.
The only one with a perception problem is you.
You were commenting on the NZ use of "intermediate ratings".
Glicko2 is superior to Glicko which is superior to Elo.
Glicko2 with "intermediate ratings" is superior to Glicko with "intermediate ratings" which is superior to Elo with "intermediate ratings".

Interesting use of the word "superior".

Personally, I don't want a superior rating system; I prefer one that is open and understandable.

Tony Dowden
31-01-2010, 08:24 AM
Bill,

My comment clearly referred to the Elo context not Glicko. (If you were involved in a discussion about the Melbourne Cup would you suddenly start talking about donkeys instead of thoroughbreds?!)

In addition, you are a well-respected ratings boffin but I don't think you are in a good position to comment on my (subjective) experience of having played over 800 rated games (over 30 odd years) within the NZ Elo rating system.

Cheers, Tony

Bill Gletsos
31-01-2010, 01:32 PM
Bill,

My comment clearly referred to the Elo context not Glicko. (If you were involved in a discussion about the Melbourne Cup would you suddenly start talking about donkeys instead of thoroughbreds?!)

In addition, you are a well-respected ratings boffin but I don't think you are in a good position to comment on my (subjective) experience of having played over 800 rated games (over 30 odd years) within the NZ Elo rating system.

Cheers, TonyYou were the one who said:

If pigs would fly we'd switch to Elo here in Australia and apply some 'jump' therapy....so it is clear it was you who originally raised the Elo V Glicko comparison above, not me.

As such you it is entirely reasonable for me to make comments regarding the NZ vs Glicko use of "intermediate ratings" etc in my response to your posts.

Tony Dowden
31-01-2010, 01:59 PM
You were the one who said:
so it is clear it was you who originally raised the Elo V Glicko comparison above, not me.

As such you it is entirely reasonable for me to make comments regarding the NZ vs Glicko use of "intermediate ratings" etc in my response to your posts.
Yes, of course you can make comments - isn't that what this forum is all about? But if you feel the need to brusquely claim that someone doesn't understand something, it would be wise to ensure you understand their point of view first :cool:

Bill Gletsos
31-01-2010, 02:05 PM
Yes, of course you can make comments - isn't that what this forum is all about? But if you feel the need to brusquely claim that someone doesn't understand something, it would be wise to ensure you understand their point of view first :cool:In the case in point you clearly did not know what you were talking about otherwise you would not have equated the "jump therapy"("use of Intermediate ratings") applied to NZ to being needed in Australia since Australia had been using "intermediate ratings" for 5 years.

Tony Dowden
02-02-2010, 08:24 PM
Thanks for explaining the 'equating' bit Bill - I guess surmising that a rough equivalence will suffice doesn't always work :)