Re: [ccp4bb] R and Rfree

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CCP4bb <-- 2007 <-- April 2007 <-- 26 April 2007

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Subject: Torsion of acetyl coenzyme a
From: Peng Zhang pzhang {- at -} SIBS {- dot -} AC {- dot -} CN
Date: 2007-04-25

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Subject: Re: R and Rfree
From: David Briggs bassophile {- at -} GMAIL {- dot -} COM
Date: 2007-04-26

Hi Sam

Dogma would state that you are trying to maximise the correlation
between your model and the structure, *without over fitting* and Rfree
should thus be minimised.

However, you are likley using a maximum likelihood target, so you
should maximise the likelihood so that the model accurately describes
the data.
(Refmac quotes likelihoods as -LLGs - so minimise this)

HTH

Dave

On 25/04/07, U Sam wrote:
> Hi Everybody,
> I have small query.
> I am feeding ions and correcting few residues into my final structure.
> If R increases and Rfree decreases or vice versa in the subsequent refinement, which one I should accept and go forward.
> Thanks.
> Sam
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CCP4bb navigation

CCP4bb <-- 2007 <-- April 2007 <-- 26 April 2007

Previous message:
Subject: Torsion of acetyl coenzyme a
From: Peng Zhang pzhang {- at -} SIBS {- dot -} AC {- dot -} CN
Date: 2007-04-25

Next message:
Subject: Protein crystallographer position available at MDC-Berlin
From: "Juergen J {- dot -} Mueller" jjm {- at -} MDC-BERLIN {- dot -} DE
Date: 2007-04-26