From the point of view of the information theory, the term relevancy i
s actual only in the case of multielement determinations, because the
information of one component determination is basically relevant. In t
he multicomponent determination the surplus of information, the s.c. r
edundancy, is given on the one hand by the relation between the inform
ation parameters of the analytical order and the equivalent parameters
derived from the experimental data. On the other hand, the informatio
n from the individual terms of determined information parameters also
have individual degrees of redundancy. But the given redundancy, the w
eight of information, is not necessarily always useful. The main probl
em is the correct and true determination of the given redundancy and f
ollowing degree of relevancy.