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Ratings after in game history are displayed incorrectly

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brusselsshrek

In the games history, the ratings incorrectly display the ratings AFTER the match, and not the ratings of the players AT THE TIME THEY PLAYED the game.

e.g.

A player of 1300 beats a player of 1500.
The ratings then change to be, say, 1340 and 1460.

After the match, the game is displayed in the history as, say, a game between a player of 1340 and 1460. No! The game was between a player of 1300 and 1500!

Of course the ratings after a match are more accurate than they are before the match, but they are not the correct ratings to display for the match.  The match (in my example) was played between a player of 1300 and 1500, NOT between a player of 1340 and 1460, and therefore it is 1300 and 1500 which should be displayed against
each player for the history of that match.

To give you another example, suppose a player of 1700 played someone of 1800
and beat them, and the new ratings were 1750 and 1750, to display that the
match was between two players of identical rating (1750) is incorrect and
thoroughly misleading. What has happened is that a player of a lower
ranking has beaten a player of a higher ranking, and that is what should be
displayed.

Isn't that what is displayed whenever you see a match listed in the chess
press, the rating at the start of the game before any recalculation based on
the result of the game?

Isn't that what I as a player would be interested in?

corum

I tend to agree with you - but that's how the system works here. I don't think it matters that much does it though? Does it make a difference how you view or interpret a match won by someone rated, say, 1900 or someone rated 1880?

brusselsshrek

I know that's how the system works here; I'm just pointing out that it's wrong, and contrary to how it works everywhere else in the world of chess.

Does it matter?  If it's a 1500 player against a 2000 player, probably not, because the differences would be small, and there's not much difference with what the grades whoever wins, but games are typically between players of quite similar grades, and so yes, there it makes much more of a difference, because it often makes the difference between say me when I am a lesser player beating a better player. 

For example imagine a match between a 1370 and a 1400 where the 1370 wins and so the new grades go 1370->1390 and 1400->1380.  What is displayed is that a I as a 1390 beat a worse player who was a 1380 grade.  This is not true at all!  I had a satisfying victory, being a 1380 player who beat a 1400 player.

brusselsshrek

Hi, Any chance of this being fixed?

rooperi

I agree, for a long time my best win was against a 1985(plus-minus), but he was over 2000 when we played. Took me a looooong time to finally get that real 2000 scalp

Tenna

A funny result of this is that, when I started playing Chess960 games (against 1200 players, of course), each successive win became my "best win" because the higher rated I became, the fewer rating points a 1200 player would lose by losing against me.

I'd like it see it changed for aesthetic reasons... actually, I've always wanted the site to display the rating change at the end of the game. That'd be the best of both worlds.

brusselsshrek

Any chance of this being fixed?

brusselsshrek

Anybody in chess.com reading these posts?  Any chance of this bug being fixed?

TadDude
brusselsshrek wrote:

In the games history, the ratings incorrectly display the ratings AFTER the match, and not the ratings of the players AT THE TIME THEY PLAYED the game.


...

Of course the ratings after a match are more accurate than they are before the match, but they are not the correct ratings to display for the match. ...

...

Isn't that what is displayed whenever you see a match listed in the chess
press, the rating at the start of the game before any recalculation based on
the result of the game?


At the time they played the match, over a period of months or years, a player's rating would not have been static. Is the rating one second before the end of the game more reasonable than the one from one second after the game or the average in the time the game was played?

One reason the chess press would use the old rating is that the new rating is not official until FIDE (or other chess federation) publishes it some months later.

http://www.fide.com/component/handbook/?id=72&view=article

"The Qualification Commission shall prepare a list six times a year which incorporates the rated play during the rating period into the previous list. This shall be done using the rating system formula based on the percentage expectancy curve and derived from the normal distribution function of statistical and probability theory."

FIDE list - http://ratings.fide.com/toplist.phtml. (Previously published four times a year.)

Live list - http://chess.liverating.org/

Nytik

This is not a bug. This is how it is supposed to work.

The ratings after each game are closer to the player's true statistical average. And it makes sense to display the most accurate rating available. In your example of 1370 vs. 1400, if the ratings change to 1390 vs. 1380, the chances are your opponent IS weaker than you.

So let's just get on with our lives! Cool

brusselsshrek

I'm sorry but I disagree.  The rest of the chess world displays the ratings of a game based on the ratings of the game when it started and not when it ended, so why should Chess.com be any different?

Xonatron

Reviving an old thread, but I just noticed this error too. It should follow chess standards, which are ratings before the match. What stands out to me is a game with an upset where the ratings change a lot, but does not properly showcase the gravity of the upset.