22-10-2011, 08:42 AM
Gary,
A few years ago, a statistician did a study of our grading system and found it to be statistically sound. We have mechanisms in place to counteract grading inflation and deflation which are the scourge of the FIDE system. As Dougie has pointed out, we have a mechanism in place that allows for the improvement of Juniors. I fail to see what the benefit is of having a rolling grade system.
For the grading system to work, it requires a sample size, that is the nature of the grading. The calculation uses n as the sample size where n is 30 unless more then 30 games have been played, on those occasions then n is the number of games played. FIDE has a similar idea, the K factor. Using rolling grades in the calculation would cause grades to fluctuate widely and destroy the stability and mechanisms we have in place.
As I mentioned earlier, out of interest I simulated what would happen if we were to grade juniors twice a year instead of once. I picked the arbitrary dates of 1 July and 1 Jan. I deliberately picked the top 20 junior risers from last season as that should have given the greatest change in final grade. I did this as I have been an advocate of 2 gradings a year for juniors for some time. To my surprise, it had little to no effect. The Final grade was always in the same ballpark as this years published grade.
Several of the Juniors went +200 points from their starting grade in both periods and given the games played, I used a value of 30 for N.
Thinking this through logically, it should have meant that we saw far greater grading rises. We didn't. What that tells me is that the current system we are using for juniors works. What puzzled me is why the following season, their grades took off again. By watching my daughter learn how to read and write at school, it dawned on me. The juniors are continually learning. I have seen Eilidh go from not being able to write (a beginner) to being able to write a sentence in a year. That is her starting point for this year and she will build on that. The same happens in chess.
I also tested by removing the junior additions for games against juniors, unsurprisingly it meant the final grades dropped. I'd argue this would exacerbate the problem.
I have now changed my opinion and I see no merit in having 2, 3 or 4 grading periods a year. Statistically it only appears to marginally benefit people who play 60+ games who do not increase their grades by 200 points.
A few years ago, a statistician did a study of our grading system and found it to be statistically sound. We have mechanisms in place to counteract grading inflation and deflation which are the scourge of the FIDE system. As Dougie has pointed out, we have a mechanism in place that allows for the improvement of Juniors. I fail to see what the benefit is of having a rolling grade system.
For the grading system to work, it requires a sample size, that is the nature of the grading. The calculation uses n as the sample size where n is 30 unless more then 30 games have been played, on those occasions then n is the number of games played. FIDE has a similar idea, the K factor. Using rolling grades in the calculation would cause grades to fluctuate widely and destroy the stability and mechanisms we have in place.
As I mentioned earlier, out of interest I simulated what would happen if we were to grade juniors twice a year instead of once. I picked the arbitrary dates of 1 July and 1 Jan. I deliberately picked the top 20 junior risers from last season as that should have given the greatest change in final grade. I did this as I have been an advocate of 2 gradings a year for juniors for some time. To my surprise, it had little to no effect. The Final grade was always in the same ballpark as this years published grade.
Several of the Juniors went +200 points from their starting grade in both periods and given the games played, I used a value of 30 for N.
Thinking this through logically, it should have meant that we saw far greater grading rises. We didn't. What that tells me is that the current system we are using for juniors works. What puzzled me is why the following season, their grades took off again. By watching my daughter learn how to read and write at school, it dawned on me. The juniors are continually learning. I have seen Eilidh go from not being able to write (a beginner) to being able to write a sentence in a year. That is her starting point for this year and she will build on that. The same happens in chess.
I also tested by removing the junior additions for games against juniors, unsurprisingly it meant the final grades dropped. I'd argue this would exacerbate the problem.
I have now changed my opinion and I see no merit in having 2, 3 or 4 grading periods a year. Statistically it only appears to marginally benefit people who play 60+ games who do not increase their grades by 200 points.
"How sad to see, what used to be, a model of decorum and tranquility become like any other sport, a battleground for rival ideologies to slug it out with glee"