Chess SA Rating system - Explanation (Second Article)
Chess SA Rating system can be a very complicated system and difficult to break down. In this Blog 2 will go into a little more depth.
First Article: Getting started on your Chess SA profile
Second Blog: Little more depth
Third Blog: Tying up the loose ends
Blog 1 explained how to start viewing your player profile on:
https://chessa.co.za/ratingsdatabase.aspx
We stopped after finding the Rating, but there were still a couple of loose ends:
- Where do you get the Swe in the tournament
- How to calculate the K factor for a tournament
- Where does Weighted rating fit in
This article will cover weighted rating and a following blog will cover the Swe and K-factor.
How to calculate Weighted performance:
(Took example from Chess SA guidelines)
Calculation:
[ 1623.5x5 (Q1 x Rt) + 1314.5 x 4(Q2 x Rt) +1356.9x3(Q1 x Rt) + 1340.4x2(Q1 x Rt) + 1524.8x1(Q1 x Rt) ]/ 15 = 1392.7
We have TWO new loose ends:
π=(2920βπππ)/2920
age = Β the difference in days between the current date (the event is processed/rated) and the end-date of the event.
Rt = R = Type of time control.
Standard: 1.00
Rapid: 0.95
Blitz: 0.90
With this player the person's profile show a rating of 1392,7, but under "Rating"-leg it says 1329.9?
It will seem that the system will give you the highest of "Rating" or "Weighted".
That is pretty neat, and work in favor of player? But why?
My best guess is that the "weighted" shows current form and the "rating" is a much slower rating.
