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Probability inverse

This is concerned with the fact that in the case of the relaxation time, roughly speaking only half of all Brownian particles should leave the initial potential minimum to reach the equilibrium state, while for the profile of the decay time case all particles should leave the initial minimum. Expression (5.120), of course, is true only in the case of the sufficiently large potential barrier, separating the stable states of the bistable system, when the inverse probability current from the second minimum to the initial one may be neglected (see Ref. 33). [Pg.411]

Fig. 3. Inversion probability density functions for the inversion states V2V with... Fig. 3. Inversion probability density functions for the inversion states V2V with...
It is important that this process results in the preferential formation of a thermodynamically stable alcohol diastereomer. The anion-radicals contain an almost undoubtedly planar C-0 and give rise to pyramidal hydroxy carboradicals. The hydroxy carboradicals form pyramidal hydroxy carbanions, which cannot exist in the presence of ammonium cation for a long time. Therefore, the equilibrium including pyramidal inversion, probably, takes place at the step of carboradical formation, rather than carbanion formation. Transformation of a carboradical into a carbanion obviously proceeds faster than its dimerization or disproportionation. As a consequence, the reduction of an optically active ketone into an alcohol goes without racemization (Rautenstrauch et al. 1981). [Pg.353]

Although compound 27 was obtained in a much higher yield than was 26, Gaskell and Joule concluded that Mechanism 2 is active in the epimerization reaction of reserpine (1). They discredited Mechanism 3 because of the incapability of the metho salts 28 and 29 to epimerize. Instead, treatment of 28 and 29 with AcOH (140°C, 3 d) resulted in inversion of Nb to yield 30 and 31, respectively, Fig. (5). It was concluded that the inversion probably occurs via C-3 - Nb bond scission. [Pg.12]

Gene mutations of other types such as inversions probably occur in addition to the two discussed above, but techniques have yet to he devised to analyze them. [Pg.714]

Chiral (E)-crotylsilanes have been utilized with Phi = NTs for Cu(I) - catalyzed syntheses of olefinic dipeptide isosteres, examples of which are shown in Scheme 70 [191]. In this case, tosylamidation occurs with allylic inversion,probably via asymmetric tosylaziridination of the C,C-double bond. The diastereos-electivity of product formation is high (>30 1) and appears to be strongly influenced by the hydroxyl group in the starting compounds. [Pg.166]

Although we have assigned a structure to the transition state so as to obtain the observed inversion, the coordination of solvent or chloride at boron and mercury is actually unknown. Ingold (1962) and Thorpe (1966) have suggested that SB2 reactions which go with inversion probably involve transition states in which bond formation lags bond 9... [Pg.249]

It was demonstrated that desilylation of the silyl thietanes 24 occurs with prevalent configuration inversion at the carbon bearing the silicon group.39 The inversion probably occurs because in this way the less crowded product is obtained (Scheme 25). [Pg.16]

Bayes theorem or the principle of inverse probability is deducible from Rule 1 and is... [Pg.200]

Dale AI (1991) A History of Inverse Probability from Thomas Bayes to Karl Pearson. Springer, New York and Berlin. [Pg.26]

This is known as Bayes s theorem or the inverse probability law. It forms the basis of a statistical methodology called Bayesian statistics. In Bayesian statistics, fi(fi) is called the prior probability of fi, which refers to the probability of fi prior to the knowledge of the occurrence of A. We call P B A) the posterior probability of fi, which refers to the probability of fi after observing A. Thus Bayes s theorem can be viewed as a way of updating the probability of fi in light of the knowledge about A. [Pg.12]

To differentiate between an always observed, continuous outcome y and a censored, continuous time to event outcome, we will refer to the latter as t,- and introduce an indicator of event, 5,. Here di— 1 if observation i s outcome time, t,-, is the time of the event of interest, for example, if observation i had a prostate cancer recurrence at time ti and Si = 0 if observation i s outcome time, is censored, for example, if observation i is lost to follow-up. Robins and Rotnitzky (1992) introduced the inverse probability of censoring weighted (IPCW) loss function for this scenario, which we can write as [ , - r c(zi)] [/(5i = 1)/P(8, = 1)]. Thus, we can weight the squared error loss for the continuous outcome by a ratio with numerator equal to whether or not observation i had the event of interest, 7(6, = 1), and denominator equal to the probability that observation i had an event of interest, P(5, = 1). The corresponding error rate for censored outcomes is the IPCW loss function averaged over all n observations. [Pg.236]

Hogan JW, Lancaster T. 2004. Instrumental variables and inverse probability weighting for causal inference from longitudinal observational studies. Slat. Methods Med. Res. 13 17-48. [Pg.167]

In this section, we construct the TMLE for this causal effect and compare the resulting estimator to the conventional unadjusted Kaplan-Meier (KM) and the so-called inverse probability of censoring weighted (IPCW) estimating equation-based estimator (Robins, 1999b Heman et al., 2000), which attempts to adjust for confounding through the g-factors of the likelihood. [Pg.186]

The behavioral pattern (BP) represents a sequence of elementary operations derived from DL Reasoning, e.g., ABCD sequence can denote A-inspection, B-pick up, C-insertion, and D-testing. By gathering information about BP together with other relevant spatial and temporal information coming form sensors, we can calculate the so-called posterior probability p x y). If we want to infer a quantity x by means of sensory datay, we can use Bayes rule to determine the inverse probability, which specifies the probability of data y assuming x was the case, as in (9.1). [Pg.116]

In robotics, this inverse probability is often coined generative model, since it describes, at some level of abstraction, how state variables X cause sensor measurements T [16]. [Pg.116]

Intramolecular Rearrangements of Tris-chelate Complexes.— Recently there has been considerable attention paid to the stereochemical non-rigidity of tris-chelate complexes and a number of reviews have dealt with the subject. Studies of NN-disubstituted dithiocarbarmato-complexes of the type [M(R R -dtc)8] (R, R = alkyl or aryl) have been extended and the results for intramolecular metal-centre inversion (probably by the Bailar trigonal-twist mechanism) are summarized for ruthenium(m) complexes in Table 29. The low values of AG and are surprising for ruthenium(m) since previous studies indicated that tris-chelates of this... [Pg.205]

From this, the inverse probability can be obtained by substituting the numerator in Eq. 6 with Eq. 8. [Pg.3839]

Ni(dddt)2 molecules. While less conductive [Pt(dddt)2]2lBr2 salts have dimers of Pt(dddt)2 molecules (Figure 5.10a), this might change the nature of the frontier orbital responsible for the electron conduction. This seems to be the reverse case to the Pd(dmit)2 conductors with the LUMO-HOMO level inversion. Probably the regular stack of M(dddt)2 will be desirable for the formation of the two-dimensional band. [Ni(dddt)2]3(C104)2 is an insulator, which has a Ni(dddt)2 trimer (Figure 5.10b). [Pg.258]


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See also in sourсe #XX -- [ Pg.12 ]




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Applying the principles of probability theory to a linear inverse problem

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