Measuring polarization via poverty and affluence

The decline of the middle class has been investigated as a principal aspect of social polarization (Wolfson 1994, 1997). Wang and Tsui 2000 have characterized a class of polarization measures by postulates on normalization, increasing spread and increasing bipolarity. The present paper generalizes this class of measures. It defines polarization by aggregating measures of poverty and of affluence, focussing on incomes outside a middle class interval. The approach is applied to German data on income distribution.