Note: In the case of a perfect or zero score the performance rating is estimated as either 400 points higher or lower, respectively, than the rating of highest or lowest rated opponent.
Note: You do not need to enter individual win, loss,
draw
results, only the total score (win=1.0, draw=0.5, and loss=0.0).
Click
the "New Rating" button to see your new estimated rating.
Click
on "Show K" to see the "K" value (see below for details) used in the
calculation.
Click
on "Show Bonus" to see how much of your rating change was due to the
bonus
calculation.
Note: K represents an estimate of player rating
volitility.
The higher
the value the more uncertain the prior rating is assumed to be, and
therefore
how rapidly a player's rating may change.
Its value
is determined from number of prior games, number of games played in the
current event, and prior rating.
Note: For unrated players with no prior games, set # of
Prior Games to zero (Current Rating will be ignored).
When all
games are either lost or won, Age is used to estimate a prior rating.
If no
value is entered for Age, a prior rating of 750 is assumed.
Note: A current limitation is the calculation may not be correct when all prior games have either been all wins or losses.
Home page: http://www.uschess.org
From USCF Calculator last updated June 14, 2002