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Rating change?

#1
This is like, a big problem, and I don't know why I didn't adress this earlier. I forgot when, but I once played a game with a person rated ~5 more than me, and I lost, and I lost 7 whole points. Later, I played a game against someone who is ~10 less than me and I lost again, but losing 6. How does this work? Same goes with wins. And also, I sometimes get 0 points for a draw, but my opponent (higher rated) got 1. How this this WORK????!?!!?!!111!??!??!

no but actually
#3
I did that, and I understood nothing. they give advanced math formulas-looking for a dierect answer
#4
Well, since it involves math...that's probably as direct an answer as you're gonna get.
#6
The math is definitely the direct answer (though I wouldn't mind seeing a derivation). But the basics are:

The goal of the rating system is to get a number that represents your strength. At first, it has no idea what your strength is. After a while, when the estimate gets better, it realizes that the quality of the estimate has improved. If you stop playing for a while, the quality of the estimate slowly lowers.

The rating estimate (what we call rating) and the quality of that rating are updated after every game, based solely on the win/lose/tie outcome. It is updated for both players.

If you win, your rating goes up and your opponent's goes down. Your rating changes more when its quality is poor; it changes less when its quality is good. Same (but opposite direction) if you lose. After a game, your rating's quality changes too. Usually it improves. But if you're on a streak, I believe it recognizes it may be off, and so the quality degrades.

Your opponent's strength also affects your rating swing. Beating a high-rated opponent gives you more points than beating a weaker one.

The same considerations are applied to your opponent independently. It is normal for the point changes to not match. This differs from most OTB play.
#7
@mrysin said in #1:
> I once played a game with a person rated ~5 more than me, and I lost, and I lost 7 whole points. Later, I played a game against someone who is ~10 less than me and I lost again, but losing 6.

The rating in your profile has two digits to the right of the decimal point (hundredths). It may have even more precision on the server. But what is shown after the game are these ratings floored to the next lower decimal. And then the adjustments are "rounded" to whatever makes the simple numbers work out. So your "7 points" lost may have been smaller than the "6 points".
#8
@mcgoves said in #6:
> The math is definitely the direct answer (though I wouldn't mind seeing a derivation). But the basics are:

obviously derivation is not given as is so basic. You have expectation function for points. estimate current strength normally distributed and you know standard deviation. Now just calculate most likely rating estimate based on these.

For those few this is not obvious Dr. Glickman's home page gives link to the original article http://www.glicko.net/glicko/glicko.pdf
#9
@petri999 said in #8:
> obviously derivation is not given as is so basic.

My statistics classes were a long time ago.
#10
@mcgoves said in #6:
> The math is definitely the direct answer (though I wouldn't mind seeing a derivation). But the basics are:
>
> The goal of the rating system is to get a number that represents your strength. At first, it has no idea what your strength is. After a while, when the estimate gets better, it realizes that the quality of the estimate has improved. If you stop playing for a while, the quality of the estimate slowly lowers.
>
> The rating estimate (what we call rating) and the quality of that rating are updated after every game, based solely on the win/lose/tie outcome. It is updated for both players.
>
> If you win, your rating goes up and your opponent's goes down. Your rating changes more when its quality is poor; it changes less when its quality is good. Same (but opposite direction) if you lose. After a game, your rating's quality changes too. Usually it improves. But if you're on a streak, I believe it recognizes it may be off, and so the quality degrades.
>
> Your opponent's strength also affects your rating swing. Beating a high-rated opponent gives you more points than beating a weaker one.
>
> The same considerations are applied to your opponent independently. It is normal for the point changes to not match. This differs from most OTB play.

thx @mcgoves -good explination

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