International
Tables for
Crystallography
Volume F
Crystallography of biological macromolecules
Edited by M. G. Rossmann and E. Arnold

International Tables for Crystallography (2006). Vol. F. ch. 16.2, p. 348   | 1 | 2 |

Section 16.2.3.5. Connection with the saddlepoint method

G. Bricognea*

aLaboratory of Molecular Biology, Medical Research Council, Cambridge CB2 2QH, England
Correspondence e-mail: gb10@mrc-lmb.cam.ac.uk

16.2.3.5. Connection with the saddlepoint method

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The saddlepoint method constitutes an alternative approach to the problem of evaluating the joint probability [{\cal P}({\bf F^{*}})] of structure factors when some of the moduli in [{\bf F^{*}}] are large. It is shown in §5 of Bricogne (1984)[link], and in more detail in Section 1.3.4.5.2.2[link] of Chapter 1.3 of IT B (Bricogne, 2001[link]), that there is complete equivalence between the maximum-entropy approach to the phase problem and the classical probabilistic approach by the method of joint distributions, provided the latter is enhanced by the adoption of the saddlepoint approximation.

References

First citation Bricogne, G. (1984). Maximum entropy and the foundations of direct methods. Acta Cryst. A40, 410–445.Google Scholar
First citation Bricogne, G. (2001). Fourier transforms in crystallography: theory, algorithms and applications. In International tables for crystallography, Vol. B. Reciprocal space, edited by U. Shmueli, 2nd ed., ch. 1.3. Dordrecht: Kluwer Academic Publishers.Google Scholar








































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