The article presents an analysis of methodological efficiency of economic sciences in conditions of detailed information typical of the contemporary system of collecting and processing of statistical data. The selection of a research method is essential for creating an effective process of creating an economic theory. Since economic activities are extremely spontaneous and changeable in character, only repeatable and formalized research methods can guarantee that economic sciences are efficient. At the same time, the economic theory should not be dominated by economy's changeability and spontaneity, either. However, the pragmatically oriented economists sometimes approve that dominance. Therefore, an indispensable element of professional awareness of any economist, as early as at the stage of further clarification of the object of the analysis and formulating of the research problem, should be a data selection and methodology of primary data processing. What should be emphasised, the functional homogeneity of a model is a precondition for effective modelling of economic phenomena.