A general class of progressivity indices is proposed which is consistent with the well-developed theory of the measurement of inequality and social welfare. In particular, we show that the more progressive a tax system, the more equal the distribution of net income and the greater the...

We present a class of social evaluation functions and inequality indices that obey standard axioms of welfare economics and that can be intuitively linked to measures of relative deprivation and economic isolation. From this, associated classes of indices of tax departure from proportionality...

An indicator of the performance of a tax (and/or benefit) system in generating a high level of social welfare is proposed. Under standard assumptions on the form of the admissible social welfare functions, the indicator is shown to be increasing in the progressivity of the system. It is also...

We propose a general class of indices of horizontal inequity that complements existing classes of progressivity and vertical equity indices. The class of horizontal inequity indices can also correct for biases in measuring a general class of inequality measures. We illustrate our results using...