Hi Saminda

Sorry for the slow response I must have missed the notification and only check this site out closely around new rating time.

This is quite difficult. If you have all the rated games that the player played you can estimate this by finding the approximate performance rating. One way of doing this is to put in a starting rating of something like 1500 and see what the new estimated rating is. Whatever you get feed that into the calculation as the starting rating and do a new estimate. Keep doing this until the starting and new rating converge to the same rating.

Note that this will only converge provided the players performance is not 100% or 0%. That is, not all wins or not all losses.

Hope this helps.

]]>This is a great tool. Thanks. Is there a way to get initial ACF rating from this tool for an unrated player? ]]>

Hi Simon,

Sorry for not seeing your message for so long. I don’t know about Stephenson’s system but if it is open and is a player’s new rating only depends on their own results (and not all results for all their opponents) then in principle it would be possible.

Cheers, Barry

]]>I’m trying to support the Lao Chess Federation, which is organising tournaments to increase the numbers of players with FIDE ratings. I actually came out of “chess retirement” of – well, how many years has WCC been at Balgownie? subtract 2 or 3 and that’s how long since I’ve played!

Can you explain to me if there is any way I can get my dormant ACF rating – 1655 – converted to a FIDE rating? If I can have a FIDE rating it will assist in the upcoming tournaments. I understand that the requirement for a rated tournament is a core of about 15% or 20% of all participants to already have a FIDE rating.

Also any suggestions of how I could get an IA qualification – maybe in Thailand rather than Oz?

I really appreciate your help.

Rod

]]>Thanks for the Glicko calculators. Is it possible for you to do the same with the Stephenson Rating System that won a Kaggle competition a few years ago to find a better Chess rating system?

]]>Rarely but still occasionally.

]]>I have just started a chess club in Cooktown Far North Queensland and I am currently looking at ways to rate the players when we have enough to organise small tournaments.

The spreadsheet looks like a great easy to use tool. However, I can’t workout how to determine the Elo (k,SD) and Glicko (c).

Please provide some clarification or if it is already somewhere on your website please point me in the direction

]]>Hi Ron

Sorry for not approving/replying sooner. Regarding the competition you could do a game by game update of ratings. This is how a lot of online server work. However if you are starting from zero information you will have a lot of transient noise in the beginning. In other words there will be a lot of movement which will not prove to be very significant until the ratings have had a chance to settle down. Also because the players from each pool (I assume) are not playing one another there will be no benchmarking between divisions until you start to have players meeting between pools (perhaps in future tournaments).

If you have some historical records you could retrospectively rate those to produce a more accurate initial rating and there then rating shifts will be more meaningful. Also if you are running a swiss draw format, a reasonable ranking helps a lot with making the tournament successful in determining the strongest player.

I hope these comments are helpful and not too late. Best of luck

Barry

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