R-factors: Difference between revisions
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== what do R-factors try to measure, and how to interpret their values? == | == what do R-factors try to measure, and how to interpret their values? == | ||
* relative deviation of | * relative deviation of | ||
=== Data quality === | |||
* typical values: ... | * typical values: ... | ||
=== Model quality === | |||
== what kind of problems exist with these indicators? == | == what kind of problems exist with these indicators? == | ||
Revision as of 07:38, 9 February 2008
Historically, R-factors were introduced by ...
Definitions
Data quality indicators
- R_sym and R_merge: the formula is (someone with LaTex knowledge please don't hesitate to fill in the formula!)
- Redundancy-independant version of the above: R_meas
- measuring quality of averaged intensities/amplitudes: R_p.i.m./R_mrgd-F
Model quality indicators
- R and R_free: the formula is (LaTex please )
what do R-factors try to measure, and how to interpret their values?
- relative deviation of
Data quality
- typical values: ...
Model quality
what kind of problems exist with these indicators?
- (R_sym/R_merge) should not be used, R_meas should be used instead (explain why ?)
- R/R_free and NCS: reflections in work and test set are not independant