Equality of opportunity with categorical data

This paper refers to some social evaluation problems when equity matters. We propose here a way of assessing the equality of opportunity that is applicable to categorical data. It consists of dividing society into groups with similar characteristics and to measure the dispersion of outcomes within those groups, from the distribution of the population in the different categories. An empirical illustration on the equality of opportunity in education is provided, using the PISA 2012 data on mathematical knowledge regarding the Spanish regions.