Hi Faisal,
CC-half standard is valuable in evaluating the cut-off of highest resolution.
Sometimes even if I/sigI is close to 1 and completeness is not as high, if
CC-half is still significant, it may be worth incorporate the extra high-res
shell data and extend the resolution. Again, if only the reliability and unbias
are carefully confirmed, and the apparent significant CC-half is not due to an
artifact of some other factors like ice ring etc.(Ref: Karplus PA and
Diederichs K. 2012 Science 336, 1030-1033
https://www.pubmed.com/pubmed/22628654)
It has yet to be appreciated by most population of the crystallography
society, unlike the I/sigI, completeness, Rsym. In particular, Rsym has
gradually less a direct measurement of the data quality and or determinant of
resolution cut-off.
Best,Conan
Hongnan Cao, Ph.D.Department of BiochemistryRice University
Date: Fri, 15 Aug 2014 01:39:48 +0530
From: faisaltari...@gmail.com
Subject: [ccp4bb] CC-half value ??
To: CCP4BB@JISCMAIL.AC.UK
Dear all
How CC-half value of a data set determines the maximum resolution limit during
data processing ?? Although much we know about the Rsym and I/Isig values of
the highest resolution shell while processing the data, what are the parameters
we need to check related to CC-half values ??
--
Regards
Faisal
School of Life Sciences
JNU
