Department of Economics. University of Melbourne. Melbourne Victoria 3010 Australia

This paper considers the relationship between equivalence scales and the reranking effects of taxation. The impact on reranking of varying an equivalence scale is divided into two effects. The first, referred to as the direct effect, increases reranking as the equivalence scale used departs from the scale that implicitly underlies the tax system. The second, referred to as the indirect effect, increases reranking as measures of adult equivalent income increase. It is argued that the equivalence scale that underlies a tax system is likely to be in the neighbourhood of the scale that minimises reranking Household data from Australia and the UK are analysed.