Hi everybody,since we seem to have a little Easter discussion about crystallographic statistics anyway, I would like to bring up one more topic.
A recent email sent to me said: "Another referee complained that the completeness in that bin was too low at 85%" - my answer was that I consider the referee's assertion as indicating a (unfortunately not untypical case of) severe statistical confusion. Actually, there is no reason at all to discard a resolution shell just because it is not complete, and what would be a cutoff, if there were one? What constitutes "too low"?
The benefit of including also incomplete resolution shells is that every reflection constitutes a restraint in refinement (and thus reduces overfitting), and contributes its little bit of detail to the electron density map. Some people may be mis-lead by a wrong understanding of the "cats and ducks" examples by Kevin Cowtan: omitting further data from maps makes Fourier ripples/artifacts worse, not better.
The unfortunate consequence of the referee's opinion (and its enforcement and implementation in papers) is that the structures that result from the enforced re-refinement against truncated data are _worse_ than the original data that included the "incomplete" resolution shells.
So could we as a community please abandon this inappropriate and un-justified practice - of course after proper discussion here?
Kay
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