This paper is devoted to a first application of the polarisation measure proposed in Esteban and Ray (1994). The aim of the exercise is to make a first reflection on the problems posed by the use of this type of measure. To that end we examine the evolution of polarisation and inequality in the interprovincial distribution of income in Spain during the period 1955-1981. Our results show that the polarisation indicators behave in a way that is markedly different from those of inequality. Similarly, we confirm that the c~ parameter of sensitivity to polarisation gives rise to a family of indexes that exhibit greater disparity with respect to inequality. Finally, we identify the problem of high volatility of the polarisation indexes and that this volatility is sensitive to the number of income intervals being considered.

Keywords: polansation, inequality, regional economics.