Importance of the basic classification of indicators for the correct interpretation of the mutual differences between their values

This paper focuses on the identification of the main criterion for the classification of basic indicators and their corresponding scales (nominal, ordinal, interval and ratio). The criterion is the number of meaningful categories of the formulation or measurement of all mutual differences of all potential values of the indicator. The paper insists on the necessity of distinguishing at least four types of the given indicator. The classification (and differences) of the indicators is included in the enclosed table. The purpose of the table is to: give information about the data arranged in an ordering scheme; further evaluate whether their differences are determined or they are meaningless; and investigate whether differences between values can be found and if ratios are meaningful or not. The meaning of the classification of indicators for a correct interpretation of the mutual differences between their values is emphasized.