Well, either there haven't been any replies yet or my institution's
email server is unhappy with me (if it's email problems, sorry if I'm
duplicating other responses).
> This instance leaves room for some concern about the verification of
> deposited structure factors: what happened here is consistent with the
> hypothesis that the standard-deviation field is ignored entirely, or at
> least that no plausibility check is carried out on the values deposited in
> it.
My experience with re-calculating maps from deposited models and
amplitudes, although non-systematic, leads me to believe that little or
no checking is done on deposited amplitudes. In one instance, the
listed resolution was off by a factor of 10 (listed as ~20 Angstroms for
a ~2 Angstrom structure). In another, the data listed as amplitudes
were actually intensities (at least, treating the data as intensities
allowed me to reproduce the reported R-factor).
My supposition is that part of the reason for the lack of checks on
amplitude data is the lack of crystallography software that deals
natively with cif formatted data. It would seem to make more sense to
me to make changes on the PDB end (allowing deposition of data in mtz or
cns format, converting to cif internally as needed for archiving) rather
than on the data processing side; since this might allow for easier
sanity checking.
Pete
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