There was a change to the ACF rating calculation in 2003 which scales down rating adjustments for players with ratings over 2200. For ratings that are less than 2200, then the old Glicko Calc works fine. If your rating is greater then 2300 then changes should be scaled by 75% of the Glicko Calc amount; and for rating in between 2200 and 2300, changes are scaled according or a linear interpolation between 1 and 0.75.

The short story is that I have now implemented this scaling in Glicko Calc and so that facility should be a more accurate predictor of ACF rating changes for players rated over 2200.

Enjoy!

The March 2015 ratings have now been added to the download area and into the Glicko Calculator/Rating History database. This was a bit delayed on previous cycles mainly due to an website stability issue which I have been trying to get sorted. Hopefully this issue is now fixed and the site will be more reliable and ratings have been updated too. Apologies for any inconvenience caused by the site stability or by the slow updating of ratings.

The December 2014 ratings have now been added to the download area and into the Glicko Calculator/Rating History database.

The September 2014 ratings have now been added to the download area and into the Glicko Calculator/Rating History database.

The June 2014 ratings have now been added to the download area and into the Glicko Calculator/Rating History database.

The March 2014 ratings have now been added to the download area and into the Glicko Calculator database. This has happened in record time (all data in place by 00:40 CSDT on March 1) due to the streamlining efforts I applied a few months ago. Enjoy!

With the new Rating History function I added a second rating database which contains all master file entries for the last 50 or so rating periods, including the most recent rating period. This meant there was some duplication of data since the Glicko-1 Calculator also has a lookup feature that was still looking at a copy of the active list I kept in a separate table. This also entailed a certain amount of duplication of effort when new rating lists are published or updates are released as I would need to make the updates in two places.

To overcome all this I have changed the Glicko-1 Calculator lookup to refer to the new tables I created for the Rating History. At this stage the Calculator just picks up the latest rating period but this could be changed in the future so that Calculator users could select the rating period they wish to use for lookups. It also simplifies my processing of new files and updates as I only need to do this in one place now.

The new lookup functionality in Glicko-1 Calculator should be indistinguishable from the old – all that has changed is the source of the data. However, if you notice any problem or even any differences, please let me know.

The December 2013 ratings have now been added to the download area and into the Glicko Calculator database. I’ve also managed to get around to replying to messages posted over the last little while. Sorry for any delays.