| Mike Nolan 2005-04-07, 6:08 pm |
| "Angelo De Pa1ma" <adpspammersgotohell@tellurian.net> writes:
quote:
>Wait a minute. Are you saying that for two 1800 players, the one who has a
>2300 performance rating over 3 games gets a higher bonus than one who has it
>over 5 games? That doesn't make sense.
Performance rating has NO impact on bonuses, it isn't even computed any more!
Since 'Actual - Expected' performance can be larger for a 5 round event
than for a 3 round event, in general bonuses can be larger as well.
However the bonus is reduced by 10 x the square root of the number
of games. That means that for a 3 round event, the bonus will be 17
points less than the ratings gain from the standard formula while for
a 5 round event it will be 22 points less than the ratings gain from the
standard formula.
Suppose your 1800 players go 3-0 and 5-0 respectively against players
also rated 1800.
That would be a 2200 performance rating for both players.
'Actual - expected' performance for the one who played 3 rounds is 1.5
while 'actual - expected' performance for the one who played 5 rounds is 2.5.
For an established 1800 player, the K factor is 23.5234 for a 3 game event
and 22.21686 for a 5 game event.
Thus the ratings gain (before bonuses) for the 1800 player who went 3-0
is 1.5 x 23.5234 or 35 points and the bonus is 18 points, for a total gain
of 53 points.
For the 1800 player who went 5-0, the ratings gain (before bonuses)
is 2.5 x 22.21686 or 55 points and the bonus is 33 points, for a total
gain of 88 points.
In other words, both the gain before bonuses and the bonus are larger
for the player with more games, DESPITE HAVING THE SAME PERFORMANCE RATING.
--
Mike Nolan
|