Re: [ccp4bb] Rsym problems...maybe???

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: geometry problems with sugars
From: tirumal ch_tirumal {- at -} YAHOO {- dot -} COM
Date: 2010-04-22

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Subject: Re: Rsym problems...maybe???
From: Frank von Delft frank {- dot -} vondelft {- at -} SGC {- dot -} OX {- dot -} AC {- dot -} UK
Date: 2010-04-22

Subject: Re: Rsym problems...maybe???
From: James Holton JMHolton {- at -} LBL {- dot -} GOV
Date: 2010-04-22

R-statistics are unstable for weak data (such as systematic absences).
Ignore R-sym for your highest-angle bin.

I/sdI is more informative, and from the look of yours I would say you
can "reduce" your resolution in the sense that you probably have useful
data (I/sdI > 1) to better than 2.5 A. Some people may wish to cut
their resolution for refinement, which is fine by me as long as you note
this and deposit all your data.

Also, I'm told that British journals don't like the word "redundancy"
since it has a negative connotation in their language. Try using
"multiplicity" whenever possible. Although I admit I am still not sure
how to re-phrase "highly redundant data set" without using more ink.

-James Holton
MAD Scientist

Daniel Bonsor wrote:
> Hello again.
>
> At first I was not worry but maybe now I am. I have completed a structure and submitted to the PDB. They queried my Rsym value in the highest resolution bin, 2.5-2.37A (may I dare say it 100%). I was not worried at the time as I had:
>
> 99.4% completeness
> Mean(I/sdI) of 2.5
> and a redundancy of 11 (which would explain the high Rsym)
> Space group I422
>
> My Rpim in this shell is 30%.
>
> Should I reduce the resolution and start from scratch again or is everything fine and dandy and I should stop worrying?
>

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: geometry problems with sugars
From: tirumal ch_tirumal {- at -} YAHOO {- dot -} COM
Date: 2010-04-22

Next message:
Subject: Re: Rsym problems...maybe???
From: Frank von Delft frank {- dot -} vondelft {- at -} SGC {- dot -} OX {- dot -} AC {- dot -} UK
Date: 2010-04-22