Discriminate function analysis advantages

Previous experience has shown that some markers are important, while others are only of minor value. Sensitivity may be improved to over 80% with certain combinations of single tests, in particular when the principle of discriminant functional analysis is applied (D.M. Chalmers el ah, 1981). In order to examine chronic alcohol consumption, a triple test combination would be of advantage, which, in the individual case, could be supported by additional values derived from the set of four tests, (s. tab. 28.6) When determining and differentiating acute alcohol consumption, the values of the triple test combination can be upgraded by additional tests for better clinical reliability. This would also help to determine important, so-called alcohol-typical emergency situations, including Zieve s syndrome, (s. tab. 28.6)... 

However, the current implementations of the discriminant analysis approach to qualitative analysis via NIR spectroscopy use Mahalanobis distances rather than linear discriminant functions because of their other characteristic Linear discriminant functions do not permit as straightforward a means of detecting outliers and samples not in the training set as Mahalanobis distances do, in addition to other advantages that will be considered further on. 

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