Factual Interpretation of Analytical Results

Together with a median it has to be said which type of median has been computed (see the footnote in Sect. 4.1.2) and also which kind of uncertainty (derived from median absolute deviation, mad Xi, or quantiles see Danzer [1989] Huber [1981] Hampel et al. [1986] Rousseeuw and Leroy [1987]). 

Geometrical means have unsymmetrical uncertainty intervals which are characterized by a dispersion factor v (see Sect. 4.1.2, Eq. (4.20)) and a covering factor k (see Sect. 4.2). Corresponding results should be given in the form 

That means the uncertainty interval covers the range x/(U(xgeom))... x-U(xgeom) = x/(kv).. .x-kv. Negative values of concentration at the lower limit of uncertainty do not appear in this case. 

Example Uranium has been found in wine in a concentration of 2.0 ng/L. The dispersion factor v has been estimated v = 1.2 and the coverage factor has been chosen k = 2. Then the uncertainty factor amounts vA = 1.45 and the analytical result has to be presented in one of the following ways  

Analytical investigations are always carried out to serve a definite purpose. In this respect analytical results have to be evaluated and interpreted. In modern fields of applications like environmental monitoring, foodstuff control, medical laboratory diagnostics etc., conclusions have to be drawn about the presence of given species and their amount as well as the exceeding of limit values or falling significantly below them. 

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