view article

Figure 4
Application of the Hamilton R-factor ratio test to validate use of a fully anisotropic model for carbonic anhydrase at various resolutions. The simpler model is a hybrid model that contains 16 TLS groups in addition to Biso terms for each atom. The more complex model contains a full anisotropic description Uij for each atom. In each panel the condition in (4)[link] is satisfied, indicating that the fully anisotropic model is statistically justified, only where the yellow surface is above the blue surface. (a) At 1.3 Å resolution the fully anisotropic model is clearly justified. (b) At 1.5 Å resolution the test is not conclusive, although it indicates that the hybrid model is preferable for most possible values of the effective restraint weights. (c) At 1.7 Å resolution the fully anisotropic model can be justified only under the very unlikely hypothesis that the effective restraint weights are so strong as to act as constraints.

Journal logoSTRUCTURAL
ISSN: 2059-7983
Follow Acta Cryst. D
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds