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Degrees of freedom, use

Von Neumann s and Brilloun s assertions are both certainly very plausible ones, in view of the fact that each mechanical degree of freedom used to store one bit of information (such as a capacitor, for example) involves at least an amount of kT of thermal noise which must then apparently be overcome to reliably read or manipulate the given bit of information [benn82]. We have inserted the word apparently in quotes, however, because this supposition is now known to be false ... [Pg.310]

The elements of the covariance matrix of the parameter estimates are calculated when the minimization algorithm has converged with a zero value for the Marquardt s directional parameter. The covariance matrix of the parameters COV(k) is determined using Equation 11.1 where the degrees of freedom used... [Pg.257]

The answer to this question is in the residuals. While the residuals might not seem to bear any relationship to either the original data or the errors (which in this case we know because we created them and they are listed above), in fact the residuals contain the variance present in the errors of the original data. However, the value of the error sum of squares is reduced from that of the original data, because of the subtraction of some fraction of the error variation from the total when the row and column means were subtracted from the data itself. This reduction in the sum of squares can be compensated for by making a corresponding compensation in the degrees of freedom used to calculate the mean square from the sum of squares. In this data the sum of squares of the residuals is 5.24 (check it out). [Pg.70]

An alternative route to implement local MC moves is provided by the literature on (inverse) kinematics, such as on control systems for robotic arms composed of flexible joints [27,87]. Here, the problem is transformed to either a set of linear equations [27] or finding the roots of a high-order polynomial [87] at comparable computational expense. One of the benefits of such an approach is the ability to introduce arbitrary stiff segments into the loop, that is, the degrees of freedom used for chain closure do not have to be consecutive. Conversely,... [Pg.64]

The problem of first-principles calculations of the electronic structure of solid surface is usually formatted as a problem of slabs, that is, consisting of a few layers of atoms. The translational and two-dimensional point group symmetry further reduce the degrees of freedom. Using modern supercomputers, such first-principles calculations for the electronic structure of solid surfaces have produced remarkably reproducible and accurate results as compared with many experimental measurements, especially angle-resolved photoemission and inverse photoemission. [Pg.117]

The number of degrees of freedom used for tcritical is XjXjXR"... [Pg.120]

An F ratio test is hardly needed to decide whether the variances are different A t-test is still applicable but needs to be modified to take into account the variance differences. This is done by calculating the effective number of degrees of freedom using Satterthwaite s method.This is still an area which is controversial and a number of differing approaches and equations have been proposed. [Pg.62]

It has been suggested that the number of degrees of freedom used in the calculation of RMSEC and C,i-a/2 is determined by the approach of pseudodegrees of freedom proposed by Van der Voet [66]. [Pg.228]

The number of degrees of freedom used with the chi-square distribution associated with the 2-dimensional distribution would be (N- 1)(M- l)-m, where m is the number of independent parameters estimated from the measurements. For the -dimensional case, the degrees of freedom used with the chi-square distribution would be (N1- )(/V, - I)... (Nf - I) - m, where m is the number of independent parameters estimated from the measurements. The steps used in the implementation of the chi-square test of independence are essentially the same as those listed for the chi-square test for goodness of fit. The only difference is that the expected values must be calculated for all NxM cases in the two-dimensional distribution and for all. .. Nk cases in the -dimensional distribution. The expected values for the cells are often arranged in a table that resembles the contingency table or are sometimes included, inside parentheses, within the same cell of the contingency table as the measurement. [Pg.157]

Remark on the multivariate degrees of freedom used in this section Because we are only interested in presenting the main points of MVDA, we shall not report the degrees of freedom in detail but rather indicate by a subscript number the different expressions of such degrees of freedom.The exact value of C, or the involved degrees of freedom,... [Pg.183]

Henriksen, N.E. and Heller, E.J. (1989). Quantum dynamics for vibrational and rotational degrees of freedom using Gaussian wave packets Application to the three-dimensional photodissociation dynamics of ICN, J. Chem. Phys. 91, 4700-4713. [Pg.393]

Mean centering changes the number of degrees of freedom in a principal component model from k to k + 1. This affects the number of degrees of freedom used in some statistical equations that are described later. [Pg.78]

In 1989, Malinowski observed that the magnitude of secondary eigenvalues (called error eigenvalues ) with pure random error are proportional to the degrees of freedom used to determine the eigenvalue [16]. [Pg.93]

The terms 1 and n - k gives the degrees of freedom used for comparing the calculated / -value of a single unknown spectrum with a tabulated / -value. The quantity n - k is used when no mean correction is used. If mean correction is used, then the quantity n - k - 1 should be substituted in Equation 4.47. The data vectors are then classified according to the probability levels from the / -test. [Pg.101]

The point is that, corresponding to the number of degrees of freedom used in estimating s(k i), we can look up in statistical tables the absolute value of t which is exceeded with a given frequency. In this way, we can establish for a given confidence level the limits between which K( must lie. A numerical example taken from Appendix 2 will make this clearer. [Pg.377]

The second of these two equations is analogous to eqn. (63). Confidence limits for Jc can be calculated from s Jc) and the value of the statistic t corresponding to the chosen confidence level and the number of degrees of freedom used in estimating msi or ms2 ... [Pg.385]

R. W. HaU (2005) Simulation of electronic and geometric degrees of freedom using a kink-based path integral formnlation Application to molecular systems. J. Chem. Phys. 122, p. 164112(1-8]... [Pg.681]

The probability distribution of r is a bell-shaped curve, similar to the normal distribution, see Fig. 3.11. However, the shape of the curve depends on the number of the degrees of freedom used to estimate the standard error. When this number increases, the t distribution approaches the normal distribution. [Pg.64]


See other pages where Degrees of freedom, use is mentioned: [Pg.88]    [Pg.290]    [Pg.299]    [Pg.67]    [Pg.93]    [Pg.395]    [Pg.301]    [Pg.17]    [Pg.40]    [Pg.183]    [Pg.102]    [Pg.67]    [Pg.139]    [Pg.715]    [Pg.141]    [Pg.133]    [Pg.216]    [Pg.758]    [Pg.335]    [Pg.133]    [Pg.758]    [Pg.382]    [Pg.413]    [Pg.405]    [Pg.132]    [Pg.213]    [Pg.696]    [Pg.246]    [Pg.92]    [Pg.287]   


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