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Bayes equation

However, equation 2.(i-2 IS valid because A, B are commuting variables that lead to equation 2.6-3. Rearranging, results in one of the usual forms of the Bayes equation (equation 2.6-4). PiA E) is the prior probability of A given E. P(B A E is probability that is... [Pg.51]

Fullwood, R. et al., 1977, Application of the Bayes Equation to Predicting Reactor System Reliability, Nucl. Technol. 34 p 341, August. [Pg.478]

Friedman [12] introduced a Bayesian approach the Bayes equation is given in Chapter 16. In the present context, a Bayesian approach can be described as finding a classification rule that minimizes the risk of misclassification, given the prior probabilities of belonging to a given class. These prior probabilities are estimated from the fraction of each class in the pooled sample ... [Pg.221]

The paper by Szilard in 1929 (3) is a landmark for it showed how information influenced the process. But Szilard was not the first. In 1911, Van der Waals surmised a close connection between the Second Law and Bayes equation in statistical inference 04). (Today, we can demonstrate an essential connection between the two, but that is getting ahead of our story.) In 1930, G.N. Lewis wrote "Gain in Entropy means loss of information, nothing more"... [Pg.277]

The Bayesian approach is one of the probabilistic central parametric classification methods it is based on the consistent apphcation of the classic Bayes equation (also known as the naive Bayes classifier ) for conditional probabihty [34] to constmct a decision rule a modified algorithm is explained in references [105, 109, 121]. In this approach, a chemical compound C, which can be specified by a set of probability features (Cj,...,c ) whose random values are distributed through all classes of objects, is the object of recognition. The features are interpreted as independent random variables of an /w-dimensional random variable. The classification metric is an a posteriori probability that the object in question belongs to class k. Compound C is assigned to the class where the probability of membership is the highest. [Pg.384]

For the turbulent flow of water in layer form down the walls of vertical tubes the dimensional equation of McAdams, Drew, and Bays [Trans. Am. Soc. Mech. Eng., 62, 627 (1940)] is recommended ... [Pg.562]

Equation (5-47b) is based on the work of Bays and McAdams [Jnd. Eng. Chem., 29, 1240 (1937)]. The significance of the term L is not clear. When L = 0, the coefficient is definitely not infinite. When E is large and the fluid temperature has not yet closely approached the wall temperature, it does not appear that the coefficient should necessarily decrease. Within the finite limits of 0.12 to 1.8 m (0.4 to 6 ft), this equation should give results of the proper order of magnitude. [Pg.562]

Cascade coolers are a series of standard pipes, usually manifolded in parallel, and connected in series by vertically or horizontally oriented U-bends. Process fluid flows inside the pipe entering at the bottom and water trickles from the top downward over the external pipe surface. The water is collected from a trough under the pipe sections, cooled, and recirculated over the pipe sections. The pipe material can be any of the metallic and also glass, impeiMous graphite, and ceramics. The tubeside coefficient and pressure drop is as in any circular duct. The water coefficient (with Re number less than 2100) is calculated from the following equation by W.H. McAdams, TB. Drew, and G.S. Bays Jr., from the ASME trans. 62, 627-631 (1940). [Pg.1087]

For example, Stolorz et al. [88] derived a Bayesian formalism for secondary structure prediction, although their method does not use Bayesian statistics. They attempt to find an expression for / ( j. seq) = / (seq j.)/7( j.)//7(seq), where J. is the secondary structure at the middle position of seq, a sequence window of prescribed length. As described earlier in Section II, this is a use of Bayes rule but is not Bayesian statistics, which depends on the equation p(Q y) = p(y Q)p(Q)lp(y), where y is data that connect the parameters in some way to observables. The data are not sequences alone but the combination of sequence and secondary structure that can be culled from the PDB. The parameters we are after are the probabilities of each secondary structure type as a function of the sequence in the sequence window, based on PDB data. The sequence can be thought of as an explanatory variable. That is, we are looking for... [Pg.338]

There are two special cases for which equations 2.6-7 and 2.6-8 are easily solved to fold a prior distribution with the update distribution to obtain a posterior distribution with the sarai rm as the prior distribution. These distributions are the Bayes conjugates shown in Table 2.6-1. [Pg.51]

If the failure distribution of a component i.s exponential, the conditional probability of observing exactly M failures in test time t given a true (but unknown) failure rate A and a Poisson distribution, is equation 2.6-9. The continuous form of Bayes s equation is equation... [Pg.52]

The Bayes conjugate is the gamma prior distribution (equation 2.6-11). When equations 2.6-9 and... [Pg.52]

Combining the prior with the binomial update in Bayes s equation (equation 2.6-8) for the variable range zero to one gives equation 2.6 21 which, when integrated, this gives equation 2.6-22. [Pg.54]

In the introduction to this section, two differences between "classical" and Bayes statistics were mentioned. One of these was the Bayes treatment of failure rate and demand probttbility as random variables. This subsection provides a simple illustration of a Bayes treatment for calculating the confidence interval for demand probability. The direct approach taken here uses the binomial distribution (equation 2.4-7) for the probability density function (pdf). If p is the probability of failure on demand, then the confidence nr that p is less than p is given by equation 2.6-30. [Pg.55]

If a well proves productive, the ensuing completion operation may require an area in excess of the drilling area. This may mean allocations for frac tank placement, blenders, pump trucks, bulk trucks and nitrogen trucks. In today s economic climate, the operator should weigh the probability of success, Bayes theorem (Equation 4-373), with the cost of constructing and reclaiming an additional area needed for stimulation (Equation 4-374). Plans such as these... [Pg.1350]

These findings indicate that PGH synthase in the presence of arachidonate can catalyze the terminal activation step in BP carcinogenesis and that the reaction may be general for dihydrodiol metabolites of polycyclic hydrocarbons. Guthrie et. al. have shown that PGH synthase catalyzes the activation of chrysene and benzanthracene dihydrodiols to potent mutagens (33). As in the case with BP, only the dihydrodiol that is a precursor to bay region diol epoxides is activated. We have recently shown that 3,4-dihydroxy-3,4-dihydro-benzo(a)anthracene is oxidized by PGH synthase to tetrahydrotetraols derived from the anti-diol epoxide (Equation 4) (34). [Pg.316]

The Baffin Bay picrites (Francis, 1985) show a very good covariation of FeO, MgO, and Ni. Defined from the twelve XRF data listed in Table 1.12, the variables x = ln(FeO/MgO) and y = ln(Ni/MgO) have been fitted by the parabolic equation... [Pg.41]

Figure 1.11 Ni/MgO vs FeO/MgO relationship for the Bay of Island basalts and picrites (Table 1.12 data from Francis, 1985). The curve is a least-square parabolic fit through the data. Since D = MgoFe° remains constant, the DMg0Nl partition coefficient increases with increasing FeO/MgO [equation (1.5.10)]. Figure 1.11 Ni/MgO vs FeO/MgO relationship for the Bay of Island basalts and picrites (Table 1.12 data from Francis, 1985). The curve is a least-square parabolic fit through the data. Since D = MgoFe° remains constant, the DMg0Nl partition coefficient increases with increasing FeO/MgO [equation (1.5.10)].
Most researchers, even those who can deal with sensitivity, specificity, and predictive values, throw in the towel when it comes to Bayes theorem. This is odd, because a close look at the equation reveals that Bayes theorem is merely the formula for the positive predictive value (Box and Tiao, 1973). [Pg.954]

The group means and covariances can also be estimated robustly, for example, by the minimum covariance determinant (MCD) estimator (see Section 2.3.2). The resulting discriminant rule will be less influenced by outlying objects and thus be more robust (Croux and Dehon 2001 He and Fung 2000 Hubert and Van Driessen 2004). Note that Bayes discriminant analysis as described is not adequate if the data set has more variables than objects or if the variables are highly correlating, because we need to compute the inverse of the pooled covariance matrix in Equation 5.2. Subsequent sections will present methods that are able to deal with this situation. [Pg.214]

On the eastern margin, a small deposit of siliceous ooze is located slightly south of the equator. This deposit is associated with the coastal upwelling area near Walvis Bay (23°S). The geographic spread of this deposit is limited because the seafloor in this area lies above the CCD, so calcite dilutes the BSi. This effect increases with increasing distance from the upwelling area. [Pg.523]

Equation (5.10) is a statement of Bayes theorem. Since the theorem is proved using results or axioms valid for both frequentist and Bayesian views, its use is not limited to Bayesian applications. Note that it relates 2 conditional probabilities where the events A and B are interchanged. [Pg.76]

Note that p(xi rj) denotes the posterior probability calculated using Bayes rule and the above equations clearly convey the centroid aspect of the solution. [Pg.77]

This equation does not present a full picture of the chemical changes that occur, before Vignon and Bay [33], Silberrad and Fanner [34] and Berl and Delpy [35] identified the presence of aldehyde resins, oxalic acid and ammonia among the products of hydrolysis performed under similar conditions. [Pg.7]

This equation does not comprise the whole complex of simultaneous chemical reactions, which have already been discussed (p. 7). Later investigators (Vignon and Bay [53] Silberrad and Fanner [54], Berl and Delpy [55]) also found such products as aldehyde resins, oxalic add and ammonia. It is characteristic that from nitroglycerine hydrolysed in an alkaline medium no glycerine is recovered. Glycerine can however be obtained again when the hydrolysis is carried out in the presence... [Pg.46]


See other pages where Bayes equation is mentioned: [Pg.51]    [Pg.51]    [Pg.52]    [Pg.476]    [Pg.957]    [Pg.186]    [Pg.51]    [Pg.51]    [Pg.52]    [Pg.476]    [Pg.957]    [Pg.186]    [Pg.19]    [Pg.35]    [Pg.50]    [Pg.50]    [Pg.310]    [Pg.313]    [Pg.54]    [Pg.19]    [Pg.56]    [Pg.51]    [Pg.53]    [Pg.213]    [Pg.114]    [Pg.80]    [Pg.133]    [Pg.137]    [Pg.137]   
See also in sourсe #XX -- [ Pg.221 ]




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