Q analysis

Figure 11.3. SWICS M vs M/Q analysis to enhance R. (Courtesy G. Gloeckler, NASA.) (See color insert.)...

The second difference is that the correlations between samples are calculated rather than the correlations between elements. In the terminology of Rozett and Peterson ( ), the correlation between elements would be an R analysis while the correlation between samples would be a Q analysis. Thus, the applications of factor analysis discussed above are R analyses. Imbrle and Van Andel ( 6) and Miesch (J 7) have found Q-mode analysis more useful for interpreting geological data. Rozett and Peterson (J ) compared the two methods for mass spectrometric data and concluded that the Q-mode analysis provided more significant informtlon. Thus, a Q-mode analysis on the correlation about the origin matrix for correlations between samples has been made (18,19) for aerosol composition data from Boston and St. Louis. 

All product analysis of effluent gas streams was performed by on-line gas chromatography. Two different gas chromatographs were employed, each with heated sample valve connected to the reactor effluent stream. Analysis of light (Ci-C5) hydrocarbons and dimethyl ether was performed by a Varian 1400 GC equipped with flame ionization detector. Separation of the products was accomplished by a 20 column (1/8" O.D.) packed with Porapak Q. Analysis of hydrocarbons in the C5 to... 

Q Analysis in soft drink (Fig.5.10) Lichrosorb RP8, 10 urn 150x3 25% Pr0H,0.01% Na-dodecylsulfate in 0.025M Na2S04 30... 

Q Analysis in soft drinks, using electrochemical detection Nucleosil 5C18 250x4 MeOH- 1M NaN03-lM citric acid - 1M Na-citrate - R20 (64 10 2 3 21)(pH 6) 75... 

Eromberg, A., Nilsson, T., Larsen, B. R., Montanarella, L., Facchetti, S., and Madsen, J. Q., Analysis of chloro- and nitroanilines and -benzenes in soils by headspace solid-phase microextraction,... 

Evaluations based on the Q or R mode are also needed in connection with other multivariate methods. In general, the technique is called R analysis when the relationship among p features determined by n observations is of interest. Q analysis examines the relationship among n objects characterized by p variables. For the most frequently used approach in FA, the interpretation of the loadings can be denoted as R analysis and, as seen as follows, the evaluation of the scores as Q analysis. 

Denote the matrix of the eigenvectors that were determined from the correlation matrix by Q analysis, Uq, by U, and the eigenvector matrix of R analysis, R, by V, then decomposition of the matrix X by means of SVD reveals... 

The factor analytical solutions after R and Q analysis are interrelated as follows ... 

E. M. PAGE and R. E. MUELLER, "A Comparative Analysis of Methods for Calculating Heterogeneity Effects in Fast Critical Assemblies, Part Q Analysis," Trows. Am. JVkc/. Soc., 14, 851 (1971). 

Dang, E Chen, Y Guo, Q. Analysis of saccharides as 8-aminopyrene-l,3,6-trisulfonate derivatives by capillary electrophoresis with laser-induced fluorescence detection. Fenxi Huaxue 2000, 28, 80-83. 

We note at this point that Equation 3.10 contains a direct contribution from each promoting mode q and an interference term between pairs of promoting modes q and q. Analysis of optical spectra of aromatic hydrocarbons [87,93] and of transition... 

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