Re: SFCHECK and R-factor??

["Harry M. Greenblatt" <harry@sgjs7.weizmann.ac.il>]

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BS"D
 Hi,

>         Coming to the topic, the values of the R-factor calculated
> in SFCHECK is (in most cases) won't tally with the one reported by
> the author in the HEADER. This, if I am not wrong, may be due to
> some 'scaling' procedure involved here?
> 

At least three explanations present themselves, all of them based on
ignorance of how exactly sfcheck does its calculations:

1)  As you said, refmac has a bulk solvent correction, and  sfcheck may
not.

2)  Refmac calculates R and Rfree on separate subsets of the data,
whereas sfcheck may use all the data together for one global R-factor.

3)  Your choice of resolution limits and data cutoff criteria may differ
from those used in sfcheck.

Hope that helps,

HMG
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  Harry M. Greenblatt             |  Phone: 972-8-934-3625
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