Data comparison

This sum, when divided by the number of data points minus the number of degrees of freedom, approximates the overall variance of errors. It is a measure of the overall fit of the equation to the data. Thus, two different models with the same number of adjustable parameters yield different values for this variance when fit to the same data with the same estimated standard errors in the measured variables. Similarly, the same model, fit to different sets of data, yields different values for the overall variance. The differences in these variances are the basis for many standard statistical tests for model and data comparison. Such statistical tests are discussed in detail by Crow et al. (1960) and Brownlee (1965). 

It is always preferable to plot data so that the area under the frequency curve is normalized to 100 percent since this facilitates data comparison. 

It is obvious that calculated values are systematically lower than the experimental data. Comparison of the experimental and calculated values of coefficient p shows that along with the changes in occupancy levels that appear at elevated temperatures, inter-particular interactions also make a significant contribution. Band intensity is generally defined as the derivative of the dipole moment with respect to the normal coordinate. It is, therefore, logical to assume that thermal extension and outer-sphere cation replacement have a similar influence on the potential of inter-ionic interactions, which, in turn, lead to the intensity changes. 

Emersed electrode, 12 Energy scales and electrode potentials, 7 Energy transitions via polaronic and bipolaronic levels, 362 Engineering models, for fluorine generation cells, 539 Esin and Markov plots, 259-260 Experimental data comparison thereof, 149 on potential of zero charge, 56... 

Table II. Initiators Half-life Data Comparisons...

Plates of glass, PTFE, dolomite and marble were used. Dolomite and marble were chosen because they represent minerals found in oil reservoirs. Glass and PTFE were investigated because they represent high and low surface energy solids respectively and are good model systems for data comparisons. Liquid/solid wetting cycles were obtained for each of the solids in the liquids listed in Table III. 

Generally, the primary objective of parameter estimation is to generate estimates of rate parameters that accurately predict the experimental data. Therefore, once estimates of the parameters are obtained, it is essential that these parameters be used to predict (recalculate) the experimental data. Comparison of the predicted and experimental data (whether in graphical or tabular form) allows the goodness of fit to be assessed. Furthermore, it is a general premise that differences between predicted and experimental concentrations be randomly distributed. If the differences do not appear to be random, it suggests that the assumed rate law is incorrect, or that some other feature of the system has been overlooked. 

Assessments of these new chemicals are made by teams of multidisciplined scientists, and are based on limited firm data, comparisons to similar chemicals and estimations of exposure to humans and the environment. Generally, these PMNs contain some information on acute health effects but relatively scant information on chronic health and environmental effects. 

Some data comparisons were made of several predictive methods with steam mixture enthalpy data obtained by Professor Wormald (3). To provide a basis of comparison, Figure 6 illustrates how three methods currently in vogue in the thermodynamics world perform in predicting the enthalpy departures from ideality of methane. The predictions of the Lee-Kesler equation-of-state seem to best replicate the data, with a maximum error of 1.2 kJ/kg. 

Sparacino, G. and Cobelli, C., Deconvolution of physiological and pharmacokinetic data comparison of algorithms on benchmark problems, in Modeling and Control in Biomedical Systems, Linkens, D.A. and Carson, E., Eds., Elsevier, Oxford, 1997, pp. 151-153. 

Figure 6-16 Model Predicted and Constant Flow Polarization Data Comparison (94)...

Tab. 9.4 Rat versus human bioactivity data comparison using entries from WOMBAT.2004.1 N is the number of compounds, R is the correlation coefficient, and is the fraction of explained variance...

Group VI Donors. Oxygen and sulphur donor ligands. Oxidative addition of tetrachloro-l,2-benzoquinone to rrans-[Ir(CO)Cl(PR3)2] (R3 — Ph3 or Ph2Me) has been shown to give the Ir ° products [Ir(02CgCl4)(C0)Cl(PR3)2], whose structures (45) were confirmed from far-i.r. and H n.m.r. data. Comparison... 

An example of a schematic for sample treatment, extraction, and separation procedures is given in Simoneit, and it follows the method first used by Simoneit and Mazurek with minor modifications for data comparison purposes. The samples are powdered and dried, then typically extracted using ultrasonic agitation multiple times with a mixture of dichloromethane (CH2CI2) and methanol (3 1 v/v). The solvent extracts are filtered through an annealed glass fiber filter for the removal of insoluble particles, concentrated by rotary evaporation and then by a stream of filtered nitrogen gas. 

Young and Hawkins have analyzed the same dataset using recursive partitioning and the same designs from the training data. Comparison with their results reported in Chapter 12 suggests that both cluster classification and CBA are competitive with recursive partitioning as predictors of active compounds. 

Staehelin, J., A. Renaud, J. Bader, R. McPeters, P. Viatte, B. Hoeg-ger, V. Bugnion, M. Giroud, and H. Schill, Total Ozone Series at Orosa (Switzerland) Homogenization and Data Comparison, J. Geophys. Res., 103, 5827-5841 (1998a). 

These data comparisons were used by Hummel Berner (2002) to estimate values for the missing formation constants of the mixed carbonate hydroxide complexes of U4+, Np4+ and Pu4+, and for various missing com-plexation constants of Np3+ and Pu3+. The estimated constants were used as limiting values in performance assessment but are not included in the Nagra/PSI TDB 01/01. 

In the proposed criteria, the linear model was used to calculate the concentrations associated with incremental lifetime risks of 10-5. However, in response to public comment, the USEPA ultimately decided to adopt the linearized multistage model to make full use of all available data. Comparison of the values reported in the box indicates that, for most cases, the concentrations calculated by either model for a given nominal risk are very close. 

Table III shows the results on the various elements reported. The elements are arranged alphabetically by symbol. Cases where we have extrapolated or averaged data are so marked (—e.g., the averages of results for laboratory 33 in copper). Table III is the most important table here and contains all the information necessary to compile Tables IV, V, and VI. The latter are included to facilitate data comparison and interpretations. Table III is the true result of this phase of the study although we interpret it in some detail below, this is not absolutely necessary. A superficial perusal of Table III reveals discrepancies which must be caused by systematic errors in the various laboratories. A repeat of the comparative analysis program, with more uniform samples, coupled with circulation of known standards, should reduce this variation.

Abstract—The nature of the product of the reaction between an aminated silane and carbon dioxide was re-examined with the aid of simple model compounds, several amines, and several aminosilanes. Since the reaction products previously proposed include the amine bicarbonate and a carbamate derived from the amine, ammonium bicarbonate and ammonium carbamate were studied as models for the anions. Carbon dioxide adducts of neat model amines were prepared and studied. Results from a variety of techniques are summarized. Among the most useful was Fourier transform infrared (FTIR) spectroscopy of fluorolube mulls. FTIR spectra were distinctive and assignments characteristic of the two species were extracted from the spectral data. Comparisons of these assignments with the products of the reaction between carbon dioxide and various amines were made. The results indicate that alkylammonium carbamates are the principal product. Nuclear magnetic resonance (NMR) spectra in D20 indicated much dissociation and were not helpful in defining the products. 

Mathematical models that incorporate both flow and evaporative-loss mechanisms have been prepared (158). Non-Newtonian features have been introduced recently to refine the modeling efforts and have resulted in models with quantitative predictive abilities (159). Hence, data comparison between films spun on different spinners, with nominally identical final rotation speeds, may reveal differences in film uniformity. 

Several European intensive short-term ( campaign-type ) projects have provided important information on the atmospheric aerosol properties in Europe, usually by concentrating on specific aerosol properties or interactions. However, these kinds of campaign-type measurements do not necessarily represent the seasonal or annual variations of the aerosol concentrations and can overestimate some properties of the aerosol populations. Long-term measurements, especially with intercalibrated instruments and common data handling and calibration protocols make the data comparison between stations much more reliable and provide the end users (e.g., atmospheric modelers) good datasets to compare with. 

The specific heat of coal (Table 7.2) usually increases with its moisture content (Figure 7.1), decreases with carbon content (Figure 7.2), and increases with volatile matter content (Figure 7.3), with mineral matter content exerting somewhat less influence. The values for the specific heats of various coals fall into the general range 0.25 to 0.37, but as with other physical data, comparisons should be made only on an equal (e.g., moisture content, mineral matter content) basis. 

Fig. 4.4. A histogram of fluorescence and contour plots (plotted according to different line assignments) of the same data. Comparison between the histogram and the contour plots allows us to see at what altitudes the contour lines have been drawn for each contour plot and why the resulting displays look so different.

In order to validate the theoretical model, the predictions of the numerical simulations were compared with experimental data. Comparison between the results of the... 

The mass spectrum corresponding to this peak (Figure 6b) matches well with the spectrum obtained from the drug standard, and also with the (Wiley NBS) library spectrum. Using the accurate mass measurements obtained on the FTMS data, comparisons can be made between the standard and the unknown. Based on twelve... 

QA samples are valuable tools in detecting data quality problems, and as such, they are recommended by the EPA (EPA, 1997c). QA splits may be useful for making decisions on data quality, particularly if a data comparison is conducted while the project is still in the field. The reality, however, is quite different, and data... 

If the drug product in the registration stability study is not the same as the product used in the clinical trials, the differences must be assessed. Likewise, any differences between the drug product in the registration stability study and the product to be marketed must be assessed. All differences should be explained and justified. Release data comparisons and/or a bioequivalence study may be required, depending on the significance of the differences. 

Table 7 Qualitative coronary angiography data comparison between BRILLIANT-EU and DISTINCT...

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