Data scaling

While obtaining test data, scale-up calculations should be made regularly to determnne if the end results will be practical, particularly from the available mixing hardw are, motor pow er, etc. 

Fig. 101 Value chain network excerpt used for robust planning testing The scale of this focused value chain network is shown in table 34. Table 34 Case data scale for testing robust planning model...

High variance of the variable this, however, depends on the data scale, and is thus only appropriate if the variables are measured at a similar scale. 

Only a limited number of chemicals evoke a local quantifiable pharmacodynamic response, for example, the concentration-dependent vasoconstriction effect of corticosteroids. In these experiments, resulting skin blanching is scored visually by one or more qualified investigators, using an ordinal data scale. The lack of instrumentation has been criticized, because of possible subjective errors [25], However, approaches using the Chromameter device, although recommended by the FDA, have failed to return the desired precision [26, 27],... 

Ortiz, A.R., Pastor, M., Palomer, A., Cruciani, G., Gago, F., and Wade, R.C. Reliability of comparative molecular field analysis models effects of data scaling and variable selection using a set of human synovial fluid phospholipase A2 inhibitors. /. Med. Chem. 1997, 40, 1136-1148. 

Major steps In this type of analysis Include Initial data scaling and transformation, outlier detection, determination of the underlying factors, and evaluation of the effect that experimental procedures may have on the variance of the results. Most of the calculations were performed with the ARTHUR software package (O. 

Footnotes a Data scaled using E° for the 1st wave of acetophenone... 

While thep-value allows us the ability to judge statistical significance, the clinical relevance of the finding is difficult to evaluate from the calculated confidence interval because this is now on the log scale. It is usual to back-transform the lower and upper confidence limits, together with the difference in the means on the log scale, to give us something on the original data scale which is more readily interpretable. The back-transform for the log transformation is the anti-log. 

Since these separation factors are the basis of the data scale-up procedure, Figures 8, 9, and 10 display the separation ratios for the 380 AP experimental data selected as the system design point. 

Bubble regime (Fig. 6.26s) or deep pool 1 occurs at low vapor velocities, Discrete noncoalescing bubble swarms rise through quiescent liquid, which has a very clear surface. For the air-water system, Wallis (100> showed that this regime is unlikely to occur when vapor velocities exceed 0.15 ft/sec, and therefore, in industrial columns. It may occur in bench-scale and pilot columns where outlet weirs are tall. If this regime occurs in a test unit, caution is required in data scale-up. 

Vital et al. (131) present an extensive tabulation of tray efficiency data collected from the published literature, Data interpolation is one of the more reliable methods for obtaining tray efficiency, provided the data are good and the rules recommended for data scale-up (Secs. 7.3,6 and 7.3.7) are followed. 

Standardisation is another common method for data scaling and occurs after mean centring each variable is also divided by its standard deviation ... 

There are three methods for data scaling, as in PCA, but the relevant column means and standard deviations are always obtained from the training set. If there is a test set, then the training set parameters will be used to scale the test set, so that the test set is unlikely to be mean centred or standardised. Similar scaling is performed on both the c and r block simultaneously. If you want to apply other forms of scaling (such as summing rows to a constant total), this can be performed manually in Excel and PCA... 

CRR—Cage Repeatability Reproducibility (Gage R R) Continuous—Type of data (scale)... 

Figure 29.6. (1) Comp. C-4 (2) PETN (PC) (3) TNT (cast) (4) ANFO (bagged) ( ) nuclear equivalent (data scaled to NTS alluvium).

Figure 13. 7i calculated as a function of N from MC simulations of O(IO ) configurations (Ettets and Kaelberer ). Data scaled to represent Ar/y. 

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