> > For structures with a small number of reflections, the statistical
> > noise in the 5% sets can be very significant indeed. We have seen
> > differences between Rfree values obtained from different sets reaching
> > up to 4%.
>
> This is very intriguing indeed! Is there something specific in these
> structures that Rfree differences depending on the set used reach 4%?
> NCS? Or the 5% set having less than ~1000-1500 reflections?
Tassos, by your standards, these structures should have been described as
'tiny' and not small ... ;-) [Yes, significantly less than 1000. In one
case the _total_ number of reflections was 5132 reflections (which were,
nevertheless, slowly and meticulously measured by a CAD4 one-by-one. These
were the days ... :-)) ].
--
Dr Nicholas M. Glykos, Department of Molecular Biology
and Genetics, Democritus University of Thrace, University Campus,
Dragana, 68100 Alexandroupolis, Greece, Tel/Fax (office) +302551030620,
Ext.77620, Tel (lab) +302551030615, http://utopia.duth.gr/~glykos/
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