[Ifeffit] statistical parameters

[Michel Schlegel]

Hi everybody,

>Hi Stefano,
>
>Check out this paper:
>
>H. J. Krappe and H. H. Rossner, Phys. Rev. B 61, 6595 (2000).

Just a detail: it's page 6596.

>The authors use a Bayesian analysis, and if I recall correctly, they
>determine that the amount of actual information present is considerably
>less than that given by the commonly used Nyquist criterion. That's because
>the Nyquist criterion assumes "ideally packed" information, as if EXAFS was
>a designed radio signal. Of course, the EXAFS gods had no particular reason
>to send us information in that form, so the information content is somewhat
>lower. To me, that makes the debate between +0, +1, and +2 somewhat
>moot...lacking a better method, I generally figure I should avoid having
>Nvar more than about 2/3 of Nidp, which is certainly satisfied in your
>case. Personally, I use the +0 formula when reporting the number of
>independent points, since it is the most conservative of the commonly used
>choices.

Best regards - Michel