Just2Good

Six posts by Santa! Christmas has come early this year!

As for the ratings, my attitude is - who cares. Just a number. Play the board, not the rating!

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"The fox knows many things, but the hedgehog knows one big thing."

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The Seeing

"Glicko Ratings Simplified
I hope that if the ACF ever move away from Glicko that they change to a similar rating system such as the one below:

Maris Rating System

a) similar rating changes to Glicko
b) very easy to calculate rating changes – you can simply work them out in your head
c) reduces the affect of under-rated juniors and avoids depressing deflation that has required adjustments

a) The attached excel file has 8 scenarios with comparisons for each of the 5 RD’s (!!, !, blank, ?, ??) – that is 40 comparisons with Barry Cox’s Glicko calculator (I realise that Glicko 2 is currently used). The results are similar: within 2 points for the 16 examples with reliable ratings (!! & !).

The values used for RD are:

RD RDV
!! 30
! 15
Blank 8
? 4
?? 2.5

b) The very easy to calculate method is:
Rat Per = Op Rat +/- 400
Rel RP = Rat Per - Prev Rat
Rat Ch = Rel RP / RDV (the attached excel file shows this calculation for each comparison)

For example 1500!! wins against 1400:
1400+400=1800
1800-1500=300
300/30=10

Note to prevent the loss of rating points when winning against much lower opponents the following applies: if Pre Rat - Opp Rat > 370 then Opp Rat = Pre Rat – 370

c) What has been happening?
There is a continuous flow of juniors that have significant rating gains before they stop playing. For each of these junior rating increases, much of the rating points gained cause losses to seniors (except where they are playing in junior only events).

To reduce the affect of this, the RD of juniors should be kept flexible (RD: blank, ?, ??). This enables junior ratings to change more rapidly and far less seniors would suffer from their gains. For example, a 1300 junior win against a 1500!! senior. The senior will lose 20 points. As per the attached, the junior will only gain 20 points if !!, 40 if ! but will gain 75 if RD=blank, 150 if ? and 240 if ??.

Any comments welcome on a,b, or c
Attached Files
File Type: xls RM rat.xls (26.5 KB, 2 views"

Firegoat7

1841! 8 315 82 Kolak, Chris

Looks as if your estimates were not even close Moz. Still it doesn't really explain why his official rating is so far away from Barrys calculator. Obviously Kolaks rating has been adjusted by the rating officer. The only real consideration would be the ratings of the three young juniors.



1702!! 34 516 131 Chew Lee, Max
1860! 8 288 77 Loh, Zachary
1480!! 7 980 246 Puccini, Jack


As a side note this looked rather low in my book.
1887!! 31 253 67 Dale, Ari

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MOZ

I suggest you return and re-read my post accurately fg7.

They were not my estimates; it was a TORNELLO estimate.




The reason is given in last nights shoutbox.


What is obvious is that Kolak's rating has changed as part of the mechanised re-rating calculations done for all players participating in quarter_4 events. I see no evidence of intervention in the calculation for Kolak, if that is what you were suggesting.


These 3 particular juniors have very reliable ratings as they have played many rated games (in multiple rating pools) over recent years.


It is higher than Kolak; if that helps, fg7.

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