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Re: SFCHECK and R-factor??
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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
Dept. of Structural Biology | FAX : 4159
Weizmann Institute of Science |
Rehovot, Israel 76100 | Email: harry@sgjs7.weizmann.ac.il
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