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Re: [ccp4bb] significant drop in Rfree ?
 

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CCP4bb <-- 2008 <-- February 2008 <-- 25 February 2008
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Subject: Re: significant drop in Rfree ?
From: Ethan A Merritt merritt {- at -} U {- dot -} WASHINGTON {- dot -} EDU
Date: 2008-02-24 		Next message:
Subject: Unknown density
From: Franck Coste fcoste {- at -} CNRS-ORLEANS {- dot -} FR
Date: 2008-02-25


Subject: Re: significant drop in Rfree ?
From: Frank von Delft frank {- dot -} vondelft {- at -} SGC {- dot -} OX {- dot -} AC {- dot -} UK
Date: 2008-02-25
>> But I cannot use this error to judge whether
>> something I do to the refinement is a significant improvement
>> or not. Indirect proof through argumentum absurdum:
>>
>> Assume the su of Rfree is 0.008, and I build n waters. Rf drops
>> from 24.4 to 13.9, by 0.005, less than the su. I build n+m waters,
>> say drops by 1%. Larger than su. It seems nonsense to say that
>> building n waters is insignificent, but n+m waters is.
>>
>
> There was once a fellow named Zeno who made a similar argument.
> Aristotle was not convinced.
>
Besides, as Ian Tickle showed in *that* paper: if you add parameters,
your Rfree will change anyway - not useful if you're comparing. Hence
the usefulness of the su.

phx.

CCP4bb navigation

CCP4bb <-- 2008 <-- February 2008 <-- 25 February 2008
Previous message:
Subject: Re: significant drop in Rfree ?
From: Ethan A Merritt merritt {- at -} U {- dot -} WASHINGTON {- dot -} EDU
Date: 2008-02-24 		Next message:
Subject: Unknown density
From: Franck Coste fcoste {- at -} CNRS-ORLEANS {- dot -} FR
Date: 2008-02-25


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