Originally Posted by LuckyR
I like the 10 level NTRP system, but I would not have a "secret" behind the scenes rating. I would use either the 10 levels themselves, or at most 2 significant digits worth (1.0 to 7.0, in 0.1 increments).
I'm a bit confused. The NTRP system does effectively have the 10 levels as there is not a 3.67 level. There is 3.5 and 4.0 and you are one or the other.
But you have to have a way to determine when someone has improved or declined such that they should move into an adjacent level. The NTRP does this through having calculations to the hundredth and established periods at the end of which the rating check and level (re)assignment is done.
In your scenario, how would you calculate when someone should move up or down a level? I think that is what the debate is about, not so much having some reasonable number of levels.
IMHO, you have to go to at a minimum tenths and realistically hundredths to have a reasonable way to calculate ratings based on opponents ratings. Treating all players at a given half-point level the same would not result in an accurate system at all.
You can easily have scenarios where player A, a weak to middle 4.0 plays court 3 and has a good record players just bumped up from 3.5 and gets bumped to 4.5 because he won a lot at 4.0. While player B, a middle to strong 4.0 plays court 1 and loses more than he wins against strong 4.0s just bumped down from 4.5 and gets bumped down to 3.5 because he lost a lot a 4.0. So you have player A, probably not as strong as player B, but A gets bumped up to 4.5 and B down to 3.5, a full 2 levels apart.