[Bug-gnubg] Re: ratings formula, checker play vs. cube

[Robert-Jan Veldhuizen]

At 19:45 9/10/2003 -0400, you wrote:

> No  it doesn't, as  the cube  error is  multiplied by  an experimentally
> determined factor which takes this into account.
>
> So R = a*player_err + b* cube_err.
>
> The effect you are worrying about is taken care of by the factor b which
> is much smaller than a.

Since you're using a constant factor b, it is only taken care of in a very 
general way.

For individual games and matches, where the factor (all unforced cube 
decisions/close or acutal cube decisions) can vary by a huge amount, I feel 
pretty confident it causes a lot of noise and therefore often an inaccurate 
rating estimate, even if it's good on average.

It is also inconsistent, because checker play errors DO get divided by all 
unforced moves.

Cheers,

--
Robert-Jan Veldhuizen