[phenixbb] on Rwork and Rfree
Pavel Afonine
pafonine at lbl.gov
Thu Jan 26 15:08:26 PST 2012
Hi Dialing,
for example, it may mean the following:
we typically refine macromolecular structures using maximum-likelihood
(ML) target function and not the R-factor. Maximizing the ML target does
not necessarily mean minimizing the R-factor (although free R is
correlated with the phase error and the latter should improve with the
optimization of ML). So what you observe is slightly odd but not too
unexpected.
This is discussed to some extent here (for example):
http://www.ccp4.ac.uk/newsletters/newsletter37/08_ml.html
The other 10+ potential reasons include:
- suboptimal refinement strategy;
- target weights may need adjustment;
- ...
Pavel
> Dear All,
>
> What it means if the Rwork or Rfree increase slightly during refinement?
>
> Best regards.
>
> Dialing
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://phenix-online.org/pipermail/phenixbb/attachments/20120126/d8b40490/attachment.htm>
More information about the phenixbb
mailing list