Over the last decades, research in behavioural economics has demonstrated that individual welfare (utility), as relevant for economic decision making, depends not only on absolut but also on distributional aspects. Moreover, evidence is gathering that something similar holds for aggregate...

The paper characterizes the class of weakly decomposable (aggregable) inequality measures which satisfy a new (weak) decomposition (and agregation) property. These measures can be decomposed into the sum of the usual within-group and a between-group term which is based on the inequality between...