The main contribution of Davies and Hoy (Am Econ Rev 85:980–986, 1995) was a “necessary and sufficient” condition for comparing inequality between income distributions according to the principle of transfer sensitivity (PTS). Chiu (Soc Choice Welf 28:375–399, 2007) showed that although the condition is sufficient, it is not necessary. In this paper, we provide the correct necessary and sufficient condition, and demonstrate with a simple example how the corrected condition allows for more pairs of distributions to be ranked by PTS. The correction clarifies the connection between Lorenz curve comparisons and inequality rankings when the curves intersect.

戴维斯和霍伊 (Am Econ Rev 85:980–986, 1995) 的主要贡献是根据转移敏感性原则 (PTS) 比较收入分配不平等的“必要和充分”条件。Chiu (Soc Choice Welf 28:375–399, 2007) 表明，虽然条件是充分的，但不是必须的。在本文中，我们提供了正确的必要条件和充分条件，并通过一个简单的例子演示了更正的条件如何允许更多的分布对被 PTS 排序。修正澄清了洛伦兹曲线比较与曲线相交时的不平等排名之间的联系。