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| === Comparing two sets of structure factor amplitudes or intensities === | | === Comparing two sets of structure factor amplitudes or intensities === |
| The following is symmetric, and suitable for comparing two data sets, or two model amplitudes: | | The following is symmetric, and suitable for comparing two data sets, or two model amplitudes: |
− | <math>
| + | |
− | R_{scale}=\frac{\sum_{hkl}\vert F_{hkl,i}-F_{hkl,j}\vert}{0.5\sum_{hkl} F_{hkl,i}+F_{hkl,j}}
| + | |
− | </math>
| + | : <math> |
| + | R_{scale}=\frac{\sum_{hkl}\vert F_{hkl,i}-F_{hkl,j}\vert}{0.5\sum_{hkl} F_{hkl,i}+F_{hkl,j}} |
| + | </math> |
| + | |
| + | |
| for amplitudes, and analogously for intensities. | | for amplitudes, and analogously for intensities. |
| | | |
| === Model quality indicators === | | === Model quality indicators === |
| * R and [[iucr:Free_R_factor|R<sub>free</sub>]] : the formula for both is | | * R and [[iucr:Free_R_factor|R<sub>free</sub>]] : the formula for both is |
− | <math>
| + | |
− | R=\frac{\sum_{hkl}\vert F_{hkl}^{obs}-F_{hkl}^{calc}\vert}{\sum_{hkl} F_{hkl}^{obs}}
| + | |
− | </math>
| + | : <math> |
| + | R=\frac{\sum_{hkl}\vert F_{hkl}^{obs}-F_{hkl}^{calc}\vert}{\sum_{hkl} F_{hkl}^{obs}} |
| + | </math> |
| + | |
| + | |
| where <math>F_{hkl}^{obs}</math> and <math>F_{hkl}^{calc}</math> have to be scaled w.r.t. each other. R and R<sub>free</sub> differ in the set of reflections they are calculated from: R is calculated for the [[working set]], whereas R<sub>free</sub> is calculated for the [[test set]]. | | where <math>F_{hkl}^{obs}</math> and <math>F_{hkl}^{calc}</math> have to be scaled w.r.t. each other. R and R<sub>free</sub> differ in the set of reflections they are calculated from: R is calculated for the [[working set]], whereas R<sub>free</sub> is calculated for the [[test set]]. |
| | | |