RCSB PDB Protein Data Bank A Member of the wwPDB
An Information Portal to Biological Macromolecular Structures
PDB Home |

Item _refine_analyze.RG_work


Description

              The Hamilton generalized R factor for all reflections
               that satisfy the resolution limits established by
               _refine_analyze.RG_d_res_high and
               _refine_analyze.RG_d_res_low  and for those
               reflections included in the working set when a free R set
               of reflections is omitted from the refinement.

             sum_i sum_j w_{i,j}(|Fobs|_i - G|Fcalc|_i)(|Fobs|_j - G|Fcalc|_j)
 RG = Sqrt( ----------------------------------------------------------------- )
                          sum_i sum_j w_{i,j} |Fobs|_i |Fobs|_j

               where

               |Fobs|  = the observed structure-factor amplitudes
               |Fcalc| = the calculated structure-factor amplitudes
               G       = the scale factor which puts |Fcalc| on the
                         same scale as |Fobs|
               w_{i,j} = the weight for the combination of the reflections
                         i and j.

               sum_i and sum_j are taken over the specified reflections

               When the covariance of the amplitudes of reflection i and
               reflection j is zero (i.e. the reflections are independent)
               w{i,i} can be redefined as w_i and the nested sums collapsed
               into one sum.

                           sum_i w_i(|Fobs|_i - G|Fcalc|_i)^2
               RG = Sqrt( ----------------------------------- )
                                  sum_i w_i |Fobs|_i^2

               Ref: Hamilton, W. C. (1965). Acta Cryst. 18, 502-510.

Category

refine_analyze

Mandatory Code

no

Data Type Code

float

Enumeration Range

Minimum Value Maximum Value
0.0 n.a.
0.0 0.0

 

© RCSB PDB