Exploring variation in data on income inequality across databases and measures in post-socialist countries

Monika Wesołowska

doi:https://doi.org/10.59139/stattrans-2025-043

Exploring variation in data on income inequality across databases and measures in post-socialist countries

Monika Wesołowska Poznań University of Economics and Business, Poznań, Poland ORCID:https://orcid.org/0000-0002-1438-1962 Statistics in Transition new series, vol. 26, 2025, 4, pages: 127-150 Published online: 5 December 2025 https://doi.org/10.59139/stattrans-2025-043 Citation: Wesołowska M., 2025. Exploring variation in data on income inequality across databases and measures in post-socialist countries. Statistics in Transition new series, 26(4), pp. 127-150 https://doi.org/10.59139/stattrans-2025-043

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ABSTRACT

Despite the growing interest in income inequality, cross-country evidence often shows variation between measures and databases, which complicates research and policy evaluation. The objective of the article is to compere the consistency of data on income inequality in postsocialist countries from Central and Eastern Europe and Central Asia for the commonly used measures on the basis of leading databases in this area. Other such analyses typically focus on individual measures, databases or specific countries, which prompted the idea to fill the research gap for a targeted country group. The formulated hypotheses were to test the consistency of the following: development trends, the rankings of countries from the most to the least equal in terms of income, and the values for different measures indicated by databases. The study reveals high correlations in income inequality trends over the long term, particularly among the EU subgroups. Certain consistency was observed in the context of identifying countries with extreme income equality or inequality, and in the rankings between different measures from the same database. However, there was no full consistency, especially in non- EU countries, which highlights the impact of the methodological differences.
This article contributes to the existing body of research on income inequality by providing a broad analysis of the consistency and variability of the related data across different measures and databases, with a particular focus on post-socialist countries. It points to the importance of careful data selection when analyzing income inequality in the indicated group of countries, as individual differences between measures, databases and countries tend to affect the final results of the research.

KEYWORDS

income inequality, post-socialist countries, statistical analysis

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