Rating question

How much my rating increase when I win a game depends on the difference in rating between me any my opponent. But is it the difference at the moment the game end, or at the start of the tournament that matters?

I?m sorry if this question already has been answered.

The rating used is the rating at game end.

I think the rating changes when the game is completed, not the tournament.

Let us see if I understood this correctly.

Example:

If your rating is 1500 and you play two games against different persons, both of them also have 1500 as rating. You lose one game and win the other. Assume the following fake but rather reasonable table:

<br/>Your rating - your opponents rating:   -10     0    10<br/>Change of rating if you win:            11    10     9<br/>Change of rating if you lose:           -9   -10   -11 <br/>

If you win first and then lose your rating will go as: 1500 -> 1510 -> 1499.

But if you first lose and then win your rating will go as: 1500 -> 1490 -> 1501.

Conclusion: If you have a choice, finish the games you are going to lose first.

Is this correct?

I haven't seen the code that is use, but I fully expect that the change in rating is based on each players initial rating (game start), but is added/subtracted to current rating (at game end).

so in your example as each player started with identical ratings, the win/loss change in rating would be the same regardless of when the game was finished (10, in your example)

so it makes no difference if you win first or lose first, your final rating will be the same:

1500 > 1510 > 1500

1500 > 1490 > 1500

(actual values may be slightly different due to rounding or other issues in the calculations)

Thanks for all answers.

If I understand it correctly: Dennis belives that the rating at the start of the tournament is used, and Simon belives it's the one at the end of the game.

If you play alot of games and write down how much your rating change after each one the answer should soon be apparent. But what ever the answer is it should be in the faq, IMHO.

The rating used IS the rating you have when the game is finished.

Javerbergs is also right about the fact that you will be higher rated if you lose a game and the win a game against two opponnents that both have the same rating. The reason for this is that when your rating falls below your opponents rating your expected score will e lower.

The effect of this is that the most recent games has the most influence on your rating, which is good.

The change is based on the ratings at game end. So it pays off to resign your losing games quickly, and then you get more points for your winning games later (due to a more advantageous rating difference).

Marius

Something seems to be not quite right though, or certainly not quite as straightforward as described above.

These are my 4 latest games, with my rating, opponent's rating, whether I won/lost, and the points awarded or lost:

Me Opp Res Gain New-Me

1581 1566 won +15 1596

1596 1571 lost -17 1579

1579 1423 won +5 1584

1584 1500 won +1 1585

So. I get a lot of point when I win over someone with a similar rating, which is cool. But I lose more points when I lose to someone with a higher rating. And I win 5 points by winning against a 1423, but only 1 point when playing a 1500.

It would be interesting to collect more data, but something is weird here. I'd love to see the code :)

was your last win by 5-0, or an 'extra time' win?

Nice try Huw, but I think it wasn't a StreetSoccer game. This phenomenon has been discussed earlier at the hex forum. You can look here.

It appears when a player who has played many games (an established player) plays a game with someone who hasn't finished many (i think it's 10) games. Then the rating change for the 2nd player as usual but very little (or not at all) for the 1st. This allows new players (good or not so good) to move quickly at the rating they deserve without disturbing the ratings of other (established) players.

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