R-factors: Difference between revisions
Jump to navigation
Jump to search
(New page: 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!)...) |
|||
Line 15: | Line 15: | ||
== what kind of problems exist with these indicators? == | == 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_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 | - R/R_free and NCS: reflections in work and test set are not independant |
Revision as of 07:36, 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!)
- 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 (someone with LaTex knowledge please don't hesitate!)
what do R-factors try to measure, and how to interpret their values?
- relative deviation of
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