R-factors: Difference between revisions

205 bytes added ,  18 January 2009
m (→‎measuring radiation damage: give XDSSTAT pointer)
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== what kinds of problems exist with these indicators? ==
== what kinds of problems exist with these indicators? ==
- (R<sub>sym</sub> / R<sub>merge</sub> ) should not be used to judge [[data quality]], R<sub>meas</sub> should be used instead. The reason is that the former depend on multiplicity, whereas the latter doesn't.
* (R<sub>sym</sub> / R<sub>merge</sub> ) should not be used to judge [[data quality]], R<sub>meas</sub> should be used instead. The reason is that the former depend on multiplicity, whereas the latter doesn't.


- R/R<sub>free</sub> and NCS: reflections in work and test set are not independent if chosen randomly. It is better to choose the test set reflections in thin resolution shells (FIXME: references and programs for this).
* R/R<sub>free</sub> and NCS: reflections in work and test set are not independent if chosen randomly. It is better to choose the test set reflections in thin resolution shells (FIXME: references and programs for this).
 
* Sets of reflections used for calculating R<sub>free</sub> should be maintained throughout a project. This is nicely discussed at http://www.bmsc.washington.edu/people/merritt/xplor/rfree_example.html .


==Notes==
==Notes==
<references/>
<references/>
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