Thank you all for your help.
I like the idea just to look at the I/sigI and include more data.
I tried to process less frames to have reasonable multiplicity (3-4),
but then the I/sigI went down, too.
And there was no benefit from that.
Rmeas is always higher than Rmerge, so if my Rmerg is high I don't like
Rmeas either.
Maia
Tim Gruene wrote:
Hello Maia,
Rmerge is obsolete, so the reviewers had a good point to make you publish Rmeas
instead. Rmeas should replace Rmerge in my opinion.
The data statistics you sent show a mulltiplicity of about 20! Did you check
your
data for radiation damage? That might explain why your Rmeas is so utterly high
while your I/sigI is still above 2 (You should not cut your data but include
more!)
What do the statistics look like if you process just about enough frames so that
you get a reasonable mulltiplicity, 3-4, say?
Cheers, Tim
On Thu, Mar 03, 2011 at 10:57:37AM -0700, Maia Cherney wrote:
I see, there is no consensus about my data. Some people say 2.4A,
other say all. Well, I chose 2.3 A. My rule was to be a little bit
below Rmerg 100%. At 2.3A Rmerg was 98.7%
Actually, I have published my paper in JMB. Yes, reviewers did not
like that and even made me give Rrim and Rpim etc.
Maia
Bernhard Rupp (Hofkristallrat a.D.) wrote:
First of all I would ask a XDS expert for that because I don't know exactly
what stats the XDS program reports (shame on me, ok) nor what the quality of
your error model is, or what you want to use the data for (I guess
refinement - see Eleanor's response for that, and use all data).
There is one point I'd like to make re cutoff: If one gets greedy and
collects too much noise in high resolution shells (like way below <I/sigI> =
0.8 or so) the scaling/integration may suffer from an overabundance of
nonsense data, and here I believe it makes sense to select a higher cutoff
(like what exactly?) and reprocess the data. Maybe one of our data
collection specialist should comment on that.
BR
-----Original Message-----
From: CCP4 bulletin board [mailto:[email protected]] On Behalf Of Maia
Cherney
Sent: Thursday, March 03, 2011 9:13 AM
To: [email protected]
Subject: Re: [ccp4bb] I/sigmaI of >3.0 rule
I have to resend my statistics.
Maia Cherney wrote:
Dear Bernhard
I am wondering where I should cut my data off. Here is the
statistics from XDS processing.
Maia
On 11-03-03 04:29 AM, Roberto Battistutta wrote:
Dear all,
I got a reviewer comment that indicate the "need to refine
the structures
at an appropriate resolution (I/sigmaI of>3.0), and re-submit
the revised coordinate files to the PDB for validation.". In
the manuscript I present some crystal structures determined by
molecular replacement using the same protein in a different
space group as search model. Does anyone know the origin or
the theoretical basis of this "I/sigmaI>3.0" rule for an
appropriate resolution?
Thanks,
Bye,
Roberto.
Roberto Battistutta
Associate Professor
Department of Chemistry
University of Padua
via Marzolo 1, 35131 Padova - ITALY
tel. +39.049.8275265/67
fax. +39.049.8275239
[email protected]
www.chimica.unipd.it/roberto.battistutta/
VIMM (Venetian Institute of Molecular Medicine) via Orus 2,
35129 Padova - ITALY tel. +39.049.7923236 fax
+39.049.7923250 www.vimm.it
