> 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!)
So then I got that wrong - with that *high* a redundancy, the preceding term
becomes ~1 and linear Rmerge and Rmeas asymptotically become the same?
BR
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:[log in to unmask]] On Behalf Of
> >Maia Cherney
> >Sent: Thursday, March 03, 2011 9:13 AM
> >To: [log in to unmask]
> >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 [log in to unmask]
> >>>>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
> >>>>
> >
> >
--
--
Tim Gruene
Institut fuer anorganische Chemie
Tammannstr. 4
D-37077 Goettingen
phone: +49 (0)551 39 22149
GPG Key ID = A46BEE1A
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