Zipf's law as assessment tool of urban inequality
The paper is concerned with the topical issues of regional economics – urban inequality in the Russian Federation. Empirical investigations of Zipf's law were studied in the foreign and Russian literature. Application of this law for assessment of urban inequality using the method of least squares was substantiated. Assessment of urban inequality within the boundaries of the RF federal districts by the indices of population, volume of own production of goods and services is carried out in the paper. The authors used the data of the Federal State Statistics Service for 2014, the investigation included the settlements with the status of a town and with the population over 100 thousand people. Zipf's law displays over the entire territory of Russia. By the population index in the federal districts, Zipf's factor varies within the range from – 0.7 (Northwestern Federal District) to – 0.9 (North Caucasian Federal District). As a result of the performed analysis of the Russia's cities by the population index, Zipf's factor is within the range from –0.3 (Northwestern Federal District) to –1.2 (Central Federal District). Analysis of the volume of production of goods and services determined the range of Zipf's factor from –0.26 (North Caucasian Federal District) to – 0.7 (Central and Volga Federal Districts). By the index of population and volume of production of goods and services the following "primate cities" are determined: Moscow and Saint Petersburg, Yekaterinburg (population), which allows to draw a conclusion on their dominance in urban system and high differentiation of cities by these indices. The obtained empirical estimators prove that Russia has no intermediate group of cities macroregional centers. The results of the investigation can be used for creation of methodological tools to develop the mechanisms of smoothing of interregional inequality, program of economic and social development of cities.