ANALYSIS OF PARTY SYSTEMS BY MEASURES OF CONCENTRATION OF INEQUALITY AND ASYMMETRY OF THE PARETO CURVE

The article proposes to assess party systems using the Hoover Index (HI) and the Pareto curve skewness coefficient, PAC. Conceptually, HI is one of the simplest and most intuitive measures of inequality concentration, designed to determine the proportion of votes that must be redistributed from parties that received at least the average number of votes in elections to other parties in order to achieve an even distribution of votes. The PAC determines which parties contribute the most to overall party inequality as measured by HI. For the typology of inequality concentration in party systems, the generalized Pareto principle is used. When applying the new concept to the analysis of party systems in 18 European countries (158 electoral cases), it was found that most of them had a left-wing skewness of the Pareto curve and a concentration of inequality close to the proportion of the Pareto principle. The proposed method for assessing party systems can be considered as an independent tool, or as an addition to the currently widely used Laakso-Taagepera effective numbers of parties.