I found a practical solution to a similar problem. When I get large
gap between Rf/R in refmac I repeat the refinement in PHENIX using the
same model and the same mtz file, It has always worked for me. And I
have no theory for that observation, but the tables in publications
looked better.
Maia
Quoting "Ian Tickle" <ianj...@gmail.com>:
Jackie
I agree completely with Ed (for once!), not only for the reasons he
gave, but also that it's valid to compare statistics such as
likelihood and R factors ONLY if only the model is varied. Such a
comparison is not valid if the data used are varied (in this case you
are changing the data by deleting some of them).
Cheers
-- Ian
On Tue, Oct 26, 2010 at 2:37 PM, Ed Pozharski <epozh...@umaryland.edu> wrote:
Jackie,
please note that (at least imho) the desire to obtain "better" R-factors
does not justify excluding data from analysis. Weak reflections that
you suggest should be rejected contain information, and excluding them
will indeed artificially lower the R-factors while reducing the accuracy
of your model.
Cheers,
Ed.
On Mon, 2010-10-25 at 17:44 -0400, Jacqueline Vitali wrote:
Also if your Rmerge is high and you include all reflections in
refinement, Rfree is high. In my experience, by excluding F < sigma
reflections you drop Rfree a lot.
--
"I'd jump in myself, if I weren't so good at whistling."
Julian, King of Lemurs
