Target transformation factor analytical analysis

The only condition for the application of PLS is that several samples are available with known amounts of the compountk of interest, for calibration. Interferences and matrix effects of the unknown compounds have not to be taken into account and do not effect the accurary of the analytical result (see further Section 3.3). The presence of candidate compounds, can be confirmed one at a time by a Target Transformation Factor analysis (TTFA)... 

Varimax rotation is a commonly used and widely available factor rotation technique, but other methods have been proposed for interpreting factors from analytical chemistry data. We could rotate the axes in order that they align directly with factors from expected components. These axes, referred to as test vectors, would be physically significant in terms of interpretation and the rotation procedure is referred to as target transformation. Target transformation factor analysis has proved to be a valuable technique in chemo-metrics. The number of components in mixture spectra can be identified and the rotated factor loadings in terms of test data relating to standard, known spectra, can be interpreted. 

Gerritsen MJP, Tanis H, Vandeginste BGM, Kateman G, Generalized rank annihilation factor analysis, iterative target transformation factor analysis, and residual bihnearization for the quantitative analysis of data from liquid chromatography with photodiode array detection, Analytical Chemistry, 1992, 64, 2042-2056. 

To model analytical relationships by multiple linear regression analysis, such as in multicomponent analysis, and by target transform factor analysis... 

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