Data Item _refine.overall_SU_R_Cruickshank_DPI

General

Item name
_refine.overall_SU_R_Cruickshank_DPI
Category name
refine
Attribute name
overall_SU_R_Cruickshank_DPI
Required in PDB entries
no
Used in current PDB entries
Yes, in about 6.0 % of entries

Item Description

The overall standard uncertainty (estimated standard deviation) of the displacement parameters based on the crystallographic R value, expressed in a formalism known as the dispersion precision indicator (DPI). The overall standard uncertainty (sigmaB) gives an idea of the uncertainty in the B values of averagely defined atoms (atoms with B values equal to the average B value). N_a (sigma_B)2 = 0.65 --------- (R_value)2 (D_min)2 C(-2/3) (N_o-N_p) N_a = number of atoms N_o = number of reflections included in refinement N_p = number of refined parameters R_value = conventional crystallographic R value D_min = maximum resolution C = completeness of data Ref: Cruickshank, D. W. J. (1999). Acta Cryst. D55, 583-601. Murshudov, G. N. & Dodson, E. J. (1997). Simplified error estimation a la Cruickshank in macromolecular crystallography. CCP4 Newsletter on Protein Crystallography, No. 33, January 1997, pp. 31-39. http://www.ccp4.ac.uk/newsletters/newsletter33/murshudov.html

Data Type

Data type code
float
Data type detail
float item types are the subset of numbers that are the floating numbers.
Primitive data type code
numb
Regular expression
-?(([0-9]+)[.]?|([0-9]*[.][0-9]+))([(][0-9]+[)])?([eE][+-]?[0-9]+)?

Aliases

Alias Item Name Dictionary Name Dictionary Version
_refine.ebi_Overall_ESU_R_Cruickshanks_DPI ebi_extensions 1.0