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I've just been looking at the Edinburgh Congress grading data and apparently I scored a 2248 performance (against my 2249 CS grade).
I thought I had gained a few points or (if my round 4 opponent from Australia who has a FIDE rating but no CS grading is discounted) lost a few?!
How do the calculations work for this and would the FIDE rating of this opponent count towards my CS grading?
Thanks in advance,
Andy Burnett
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fide rated player will be counted (I'm pretty sure anyways). To calculate rating performance use <!-- m --><a class="postlink" href="http://chessscotland.com/grading/expect.htm">http://chessscotland.com/grading/expect.htm</a><!-- m --> . To get the number to use then add up your score (3.5) and divide it by no. of games (5) which gives you 0.7. Your average opps is 2098 so this is a tpr of 2098 +150 = 2248. You might still have gained points from this performance however as that is based on (actual score - expected).
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Yes, despite having a tpr of 1 point less than your rating you will have gained rating points (I think - the fact that you have increased your number of games increases the factor that your increase per game is divided by but I think you will still gain points). This is basically because you have played someone more than 400 points below you so the expected score gets stuck at 0.918 until you reach 735 points below your grade when the game doesn't count (unless you don't win...) but the tpr uses the actual grade I think.
N.B. none of this is gospel - wouldn't be surprised at all if there's something I've misunderstood about this stuff.
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We use FIDE ratings as start grade CS ratings for visitors.
The calculations are pretty much as Hamish mentioned.
Players more than 400 different are assumed to be exactly 400 different so the 1830 player is worth 1849 in the calculations of both TPR and expected scores.
The reason why TPR can be flat but actual-expected positive is because the expected score data is a curve rather than linear. So taking average opposition and taking each game individually gives a different result.
