Alun R. Coker schrieb:
> Hi All,
>
> I have been in the habit of transferring my initial free R assignments
> to any new data sets or to isomorphous data sets such as substrate
> complexes. Although theoretically this is necessary to obtain a valid
> free R many of my colleagues maintain that this is completely
> unnecessary in practice. Does anyone on the list have a view on this or
> has anyone tested to see if it makes any difference.
>
> Alun.
>
Alun,
I completely agree with you about the way how to treat R-free
reflections. If you want to have an unbiased R-free then you need to set
these reflections aside for all refinement calculations of a project,
and this applies to all datasets you collect, as long as they are
isomorphous.
This is especially important for low resolution work where the danger of
overfitting is highest.
Kay
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