COMPARISON OF SOLID SAMPLING SPECTROCHEMICAL METHODS BY MEANS OF MULTIVARIATE-STATISTICS AND INFORMATION-THEORY

Interlaboratory studies and method comparison studies can usually be e valuated by using univariate statistical procedures. Alternatively, me thods of multivariate data analysis can be applied to evaluate the rel iability of methods more generally and simultaneously for all the elem ents determined by multicomponent analyses. The investigations describ ed here were carried out to demonstrate the efficiency of multivariate and information theory evaluation techniques by comparing several mul ti-element solid sampling methods. Cluster analysis and PCA (principal component analysis) were used to compare the results of ETV-ICP-OES, solid sampling AAS, TXRF, de arc spectrometry and dc arc spectrography by multivariate methods. The results correspond significantly to the information theory evaluation according to Kerridge-Bongard's inaccura cy model of information, where both the precision and trueness of the analytical results are taken into account.