Measurement variance

Total variance measured from chromatogram = column variance + variance due to instrument volumes + variance due to electronic response time... 

The subscript f on aj denotes that this variance has units of time squared. The dimensionless variance measures the breadth of a distribution in a way... 

Now consider the determination of this parameter using the variance of the response to a pulse input. The variance measures the spread of the distribution about the mean. For a continuous distribution it is defined as... 

Robust variance measure is maximized instead of the classical variance. 

Methods of robust PCA are less sensitive to outliers and visualize the main data structure one approach for robust PCA uses a robust estimation of the covariance matrix, another approach searches for a direction which has the maximum of a robust variance measure (projection pursuit). 

Thus if an imperfect delta function is injected into a system and the mean and variance measured at two measurement locations, the tanks-in-series model can also be used to interpret the results. 

Total explained variance measures how much of the original variation in the data is described by the model. It expresses the proportion of structure found in the data by the model. Total residual and explained variances show how well the model fits... 

Variance value or variance measurement is in this case also determined by the well-known formula ... 

The positive value from the variance measurement root square is called the error mean square or standard error. 

The typical results of the wide-angle light-scattering (WALS) analysis on the latex particles that were presumed to be cores are given in Table I where the theoretical model to be fitted was either S = sphere or CS = core-shell, the variance measured the goodness of fit, the modal size parameter is given by aM = 27rr/A, aQ is the log normal breadth parameter, DM is the core diameter in ym, mi the relative refractive index of the core and m2 the relative refractive index of the shell of indicated thickness. 

The variance measures the absolute breadth of the distribution, but properties that depend on the width of the distribution would depend on the width relative to the average. For this reason the dispersion index is defined as the ratio of the weight to the number average molecular weight, which is related to the variance as follows ... 

Here p denotes the mean value E Z). Thus the variance measures the expected scatter of observations of the random variable about its mean. 

Frequently, when a series of replicate analyses is performed, one of the results will appear to differ markedly from the others. A decision will have to be made whether to reject the result or to retain it. Unfortunately, there are no uniform criteria that can be used to decide if a suspect result can be ascribed to accidental error rather than chance variation. It is tempting to delete extreme values from a data set because they will alter the calculated statistics in an unfavorable way, that is, increase the standard deviation and variance (measures of spread)j and they may substantially alter the reported mean. The only reliable basis for rejection occurs when it can be decided that some specific error may have been made in obtaining the doubtful result. No result should be retained in cases where a known error has occurred in its collection. 

The limitation of the data is that the study population from which the variance measure was derived was rather homogeneous, and the estimates were minimum requirements (Andersen et al., 2007a). 

Probe variance in kinetic rates. Compare the variance in our kinetic data to that measured by others using similar techniques. Variance in our B s similar to variance measured for Brj decay. Our a shows more variance than our second-order rates. 2i... 

Sensory scientists will agree that descriptive analysis has many applications but there is relatively little agreement as to how specific methods are developed and used. For example, subjects may or may not have been screened the number of subjects can range from as few as 5 to as many as 20 there may be a formal language development process or not the number of attributes on a scorecard may be limited references may or may not be used replication may or may not be part of the design data analysis can be simple (e.g., summary statistics such as means and variance measures) or... 

The variance measures the dispersion of the distribution. If the variance is small then the distribution is concentrated about the mean. A mathematical version of this is given by Chebychev s inequality... 

Potassium current fluctuation spectra in frog nodes (19) yield Yjr=2.9 pS in close agreement with the value obtained from single variance measurements (10). Table 1 summarizes estimates of y and obtained from fluctuation analysis. 

A given basin is typified by a statistical analysis of the density. Thus, it is possible to calculate the basin population, N, and its variance, by integrating the one-electron and the pair density over the volumes of the corresponding basins. In the statistical theory of the basin populations, the variances measure the electron fluctuation in a given basin, and the covariances [9, 52] are thought to gauge directly the covalent-ionic fluctuations in terms of weights of icmic structures. However, since the covariance values exhibit similar trends to those of the variance [9], we shall focus only on the latter quantities. 

To define the scale of segregation we need to define first the correlation function, R (r). It is very similar to the variance in the sense that the variance measures the concentration difference of a point and the mean value, whereas the correlation function considers the concentration difference between two points r distance away. Thus, R (r) is given by... 

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