[Ifeffit] Importance and Edge Step

Bruce Ravel bravel at anl.gov
Wed Jun 8 08:50:42 CDT 2005

> How about writing the relative intensities in % as well if not using
> "force to sum to 1"?

Doing so would presume a particular interpretation of the situation
where the weights don't sum to one.

You would expect the weights to sum to one if:
  1. The standards and data are all calibrated and aligned
     consistently and that any e0 parameters used in the fit are well
  2. The standards and data are all normalized consistently
  3. The set of standards is representative of the contents of the
     unknown data

If the best fit is one where the "sum to 1" constraint is lifted and
the sum deviates considerably from 1, how do I know the reason a
priori?  So I (wearing my software developer hat) am hesitant to do
what you suggest for fear of biasing the interpretation of someone
else's data.

BTW, thanks for yesterday's posting, Gerrit.  It helped me find a
pretty large number of bugs in the LCF dialog.


 Bruce Ravel  ----------------------------------- bravel at anl.gov  -or-
						  ravel at phys.washington.edu
 Environmental Research Division, Building 203, Room E-165
 Argonne National Laboratory         phone and voice mail: (1) 630 252 5033
 Argonne IL 60439, USA                                fax: (1) 630 252 9793

 My homepage:    http://feff.phys.washington.edu/~ravel 
 EXAFS software: http://feff.phys.washington.edu/~ravel/software/exafs/

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