Metrological conformity of classification of objects according to properties represented by ordinal and nominal scales

To achieve metrological conformity, the procedure of classification of objects, based on observations of ordinal and nominal properties, provides for verification of the classified data performing reference measurements followed by further consideration of their uncertainties. The result of the verification is the compliance of the categories of nominal and ordinal properties, to which their manifestations are attributed according to observations, with the categories established by the reference procedure. To account for the uncertainty of the reference procedure, a matrix of the reference relation is composed, which characterizes the correspondence of the categories established by the reference procedure to the true categories according to their definition. To obtain the classification reliability indicators, it is suggested to combine the ordinal variances of the verification matrices and the reference ratio followed by the estimation of conditional probabilities characterizing the classification reliability.