Calcium-Binding Protein Protocols Calcium-Binding Protein Protocols

Shape and Dynamics of Calcium-Binding Proteins 297
11. As can be seen from Eq. 7, larger experimental errors yield smaller χ 2 values,
leading to the acceptance of simpler models. They are also propagated to produce
larger uncertainties of the estimated parameters. This in turn diminishes the significance
levels for the acceptance of models of increased complexity. Whereas
high signal-to-noise spectra will produce desirably small experimental errors,
uncontrollable sources of noise may limit the attainable uncertainties (see also
Note 7).
12. In the absence of structural information, the magnitude of the diffusion tensor
may be estimated from the distribution of T 1/T 2 ratios (51).
13. Some authors have suggested the use of entirely dynamics-based selection
criteria (2).
Acknowledgments
J. M. Werner and I. D. Campbell thank the Wellcome Trust and the OCMS
for support. The Oxford Centre for Molecular Sciences is funded by MRC,
BBSRC, and EPSRC. A. K. Downing is a Wellcome Trust Senior Research
Fellow, and she also thanks the support of the BBSRC and the MRC.
References
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