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Standard Model criticism

Like many methods of analysis of orthogonal saturated designs proposed in the literature, the critical values for Lenth s method are obtained in the null case (all A zero), assuming this is sufficient to control the Type I error rates. This raises the question can one establish analytically that Lenth s and other proposed methods do indeed provide the claimed level of confidence or significance under standard model assumptions The rest of this chapter concerns methods for which the answer is yes. ... [Pg.275]

Also the tricritical 3-state Potts exponents (for a phase diagram, see fig. 28c) can be obtained from conformal invariance (Cardy, 1987). But in this case the standard Potts critical exponents are related to an exactly solved hard core model, namely the hard hexagon model (Baxter, 1980), and not the tricritical ones. The latter have the values crt = 5/6, = 1/18, Yt = 19/18, <5t = 20, ut = 7/12, rjt = 4/21,

tricritical exponents coincide (den Nijs, 1979). [Pg.201]

Eor this reason, in Section 11 and the Appendix we have presented a critical review of the standard Langevin, Onsager, Mori slow variable model of irreversible dynamics [1-5] that identifies the physical assumptions that underlie the model. Especially emphasized in this discussion is that the standard model emerged from attempts to explain purely macroscopic phenomena and is ultimately founded on fully macroscopic measurements. [Pg.217]

Because raw X-ray count intensities in an unknown material are ratioed to the count intensity for the same element in a standard, the ratio of the ZAF factor in the unknown relative to the standard is critical. Minimization of the difference in matrix composition between standard and unknown will minimize errors due to inaccurate ZAF factors. ZAF corrections account for (1) differences in average atomic number between standard and unknown (Z factor) (2) absorption of excited X-rays by matrix components (A factor), and (3) secondary fluorescence of X-rays by other characteristic X-rays, rather than primary beam electrons (F correction). For REE phosphates, these corrections are significant for some elements (Table 5), e g., Y and Pb. This raises the question as to the effect that the accuracy of the ZAF factors and/or application of different ZAF correction models have on the ultimate composition estimate. [Pg.354]

Abstract A systematic overview of various electric-field induced pattern forming instabilities in nematic liquid crystals is given. Particular emphasis is laid on the characterization of the threshold voltage and the critical wavenumber of the resulting patterns. The standard hydrodynamic description of nematics predicts the occurrence of striped patterns (rolls) in five different wavenumber ranges, which depend on the anisotropies of the dielectric permittivity and of the electrical conductivity as well as on the initial director orientation (planar or homeotropic). Experiments have revealed two additional pattern types which are not captured by the standard model of electroconvection and which still need a theoretical explanation. [Pg.55]

In Fig. 2, the results for the critical voltage Uth (left panels, in units of Uq = /n Ki/ eoe ), Uq = 1.19V for MBBA parameters) and the corresponding critical wavenumber Qc (right panels) are summarized as functions of e /e L. The data are barely distinguishable from the results of a rigorous linear stability analysis based on the full standard model [21]. [Pg.66]

Because of the different basis-set requirements for correlated and uncorrelated calculations, we examine the convCTgence of the Hartree-Fock and correlation energies separately, in Sections 8.4.1 and 8.4.2. Next, in Section 8.4.3, the extrapolation of the correlation energy is discussed. Finally, in Section 8.4.4, we consider the binding energy. Basis-set convergence is also studied in Section 8.5 (for van der Waals systems) and in Chapter 15, in the broader context of a critical assessment of the standard models of quantum chemistry. [Pg.315]

A variety of equations-of-state have been applied to supercritical fluids, ranging from simple cubic equations like the Peng-Robinson equation-of-state to the Statistical Associating Fluid Theoiy. All are able to model nonpolar systems fairly successfully, but most are increasingly chaUenged as the polarity of the components increases. The key is to calculate the solute-fluid molecular interaction parameter from the pure-component properties. Often the standard approach (i.e. corresponding states based on critical properties) is of limited accuracy due to the vastly different critical temperatures of the solutes (if known) and the solvents other properties of the solute... [Pg.2002]

Fig. 2. For the case of global reconstruction of the surface, the phase diagram retains a dicontinuous IPX of first order at the critical point 0.5235 0.0005, i.e., a value very close to but slightly smaller than that of the standard ZGB model given by F2A — 0.525 60 0.00001 [31]. Also, the second-order IPX of the standard ZGB model is no longer observed, in qualitative agreement with experiment, e.g.. Fig. 3. Fig. 2. For the case of global reconstruction of the surface, the phase diagram retains a dicontinuous IPX of first order at the critical point 0.5235 0.0005, i.e., a value very close to but slightly smaller than that of the standard ZGB model given by F2A — 0.525 60 0.00001 [31]. Also, the second-order IPX of the standard ZGB model is no longer observed, in qualitative agreement with experiment, e.g.. Fig. 3.
Another interesting version of the MM model considers a variable excluded-volume interaction between same species particles [92]. In the absence of interactions the system is mapped on the standard MM model which has a first-order IPT between A- and B-saturated phases. On increasing the strength of the interaction the first-order transition line, observed for weak interactions, terminates at a tricritical point where two second-order transitions meet. These transitions, which separate the A-saturated, reactive, and B-saturated phases, belong to the same universality class as directed percolation, as follows from the value of critical exponents calculated by means of time-dependent Monte Carlo simulations and series expansions [92]. [Pg.422]

ANOVA) if the standard deviations are indistinguishable, an ANOVA test can be carried out (simple ANOVA, one parameter additivity model) to detect the presence of significant differences in data set means. The interpretation of the F-test is given (the critical F-value for p = 0.05, one-sided test, is calculated using the algorithm from Section 5.1.3). [Pg.377]


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See also in sourсe #XX -- [ Pg.2 , Pg.340 ]




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Model criticism

Standard Model

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