Re: [Bug-gnubg] Possible small UI simplification

[Philippe Michel]

On Wed, 19 Aug 2015, address@hidden wrote:

> Is there any reasonof any importance, beside the not important  and VERY 
> small UI simplification, to remove the non-deterministic noise ?

It seems useless to me (but I may have missed something, that's why I 
asked) and its documentation is rather obscure. Can you read what follows 
and complete the sentence "In ... case, I absolutely have to use the 
non-deterministic choice and here's why : ..." ?


If noise is added to the evaluations GNU Backgammon will take a Box Müller 
transform of a point in the unit circle and add to each possible outcome 
probability. This means that the addition is random, but distributed so 
that it's more likely to have an noise addition close to zero than a noise 
addition close to the limit. The noise addition is limited to the number 
you put into the noise field in the dialog box.

If you check the box Deterministic noise, the noise added to each 
evaluation will be based on a sum of the bytes in the hash of the board 
position, which (by the central limit theorem) should have a normal 
distribution. In that way you will always have that same noise amount to a 
position, since the noise added to the evaluation is only depending on the 
position itself.