Rating calculation


Rating calculation

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Daniel Parmet    (2010-02-21)
Rating calculation

When you go to calculate a game's rating is it based off the rating of the players when the game started or when it ended since this can be radically different.

Thibault de Vassal    (2010-02-22 01:21:35)
Rating calculation

What do you mean exactly a game's rating?

Rating calculation takes account of the Tournament Entry Ratings (TER) for each game and of course the current player's rating when the calculation occurs.

See - http://www.ficgs.com/membership.html#rating_chess

Daniel Parmet    (2010-02-22 01:28:05)
Rating calculation

by a games rating I mean how it effects the two players ratings. So you are saying it uses both the starting and ending rating? This makes no sense! According to the link you gave it sasy TER meaning only starting rating which makes sense.

Hannes Rada    (2010-02-22 15:49:25)
Rating calculation


TER (Tournament Entry Rating) is used for elo-calculation.

Philip Roe    (2010-02-22 16:39:32)
Rating calculation

The link is not totally clear, but the way I read it, your performance is based on your opponents TERs. This is then used to modify your current rating. Am I right?

Wayne Lowrance    (2010-02-22 17:15:31)
Rating calculation

Maybe this will help: a simplification of the involved equation.
New elo= (a) x elo + (TER opponents avg.)/a
So you see a new rating is based on elo and ter. The variables (a) & (b) are simplified to remove non elo numberical values so that the expression is easier to see.
Hope this helps

Thibault de Vassal    (2010-02-22 23:20:19)
Rating calculation

Thanks Hannes, Philip & Wayne... Yes I am not clear enough, I should have used the term "performance", sorry :/

Ralph Deline    (2010-03-12 19:36:04)
Rating calculation

Hi Thibault,
Thanks for your earlier explanation. I wanted to respond sooner but then when I was at the FICGS site, I saw another player, also confused about his chess rating, questioning you about it so I threw in my two cents. In my situation, my opponent was rated about 80 points higher so when I drew, I thought I would actually go up in ratings points instead of down. That is still confusing to me.
Maybe my age is catching up with me, but for fifty years or more, using the formula for establishing ratings in Canada, I was always under the impression that your score and your opponents ratings, with a bit of math thrown in, determined your rating. I know at one time it was possible to win a tournament and lose rating points but I believe that was corrected about a decade or so ago. I wasn't playing for over a decade so I'm not certain on dates.
However, let me acknowledge the fact that I understand what you are saying, play less, win more, and your rating will improve. But I still have a hurdle to overcome. When a lower rated player ties with a highed rated player, regardless of colour, why does he get penalized instead of rewarded for achieving a result that is performing above his present rating? It doesn't seem logical.
You are probably busy and I've taken enough of your time. I don't think I will understand any explanation, you know, can't teach an old dog new tricks, so you don't have to try to explain any further. I just wanted my voice to be heard.
I have had three gross blunders in the last half year so maybe I am playing too many games. I hate to do it, but maybe I will try playing less.
Thanks for listening.

Daniel Parmet    (2010-03-12 20:58:47)
Rating calculation

A sidenote, but yes you can still win tournaments (otb at least) where you win the tournament but lose rating points. Look at the 2009 US Open where GM Jesse Krai and GM Alex Lenderman both won the event with 7.5/9 and both lost 2 rating points.

Kamesh Nookala    (2010-03-13 19:38:12)
Rating calculation


Though i agree that my Rating is calculated on the basis of my opponent's TER in the previous tour plus my present rating, i want to bring on record certain facts, just to check if there is some error.

Rating after 1st March update = 2126

Games won after 1st March, in previous tours, where my TER is lower than the opponents :-

1) Rapid B 000132 (Game# 37866)
2) Rapid B 000137 (Game# 39182)
3) Rapid B 000137 (Game# 39186 - less than 10 moves, so no points for me)
4) Rapid B 000140 (Game# 39605)

Games drawn after 1 March, from the previous tour, where my opponent has better TER than me:-

1) Rapid B 000142 (Game# 40050)

Now, the detailed stats:-

First thing happened is, i drew a game from the previous tour on 1st March itself, i.e. Game# 40050 stated above. What i got is, lost my rating by 12 points. That means (2126-12 = 2114)

I gained 9 points from a draw in the Rapid M tour, which means 2114+9 = 2123

Excluding game at S.No.3 above where the moves are less than 10, i won the remaining three and i got 0 points from three wins. My substantial rise in rating afterwards is detrimental to me and my TER in that particular tour is no consideration at all is the moot question, because, at least i felt like i deserve a single point from each win i secured :)

However, if i missed something, i regret sincerely and tender and unconditional apology :)

Thibault de Vassal    (2010-03-13 21:43:04)
Rating calculation

You have to make the difference between ratings updated in real time (like advanced chess ratings) & the FICGS correspondence chess rating calculation, the idea of those ratings updated every 2 months is to avoid peaks, consequently when you win, draw or lose three games after the last rating calculation, your future rating does not take account of the first result THEN the second one THEN the third one, it is actually completely recalculated by taking account of all results at the same time, so you DO NOT win or lose points AFTER EACH result, your performance is recalculated according to the formula explained in the rules & that looks like the french FIDE rating calculation. One thing that explains "strange" variations after 2 or 3 results only is that the rating calculation is just more accurate when you have many results & particularly when your score is near 50%.

That should answer to the discussions I had with Kamesh & Ralph, but maybe my explanations are not so clear, sorry about that again.

Ralph Deline    (2010-03-17 07:27:30)
Rating calculation

Thanks for the helpful comments. I feel much better now that I understand how ratings are derived. I made the assumption that since my rating changed after the conclusion of every game, that the past games had no influence on my future rating, that is, within the two month rating period. It is the same type of rating system I'm accustomed to; results, strength of opponents, a little math thrown in, and presto, a new rating. I can now go on living. Cheers.