International Income Inequality: Measuring PPP Bias by Estimating Engel Curves for Food
估计了宾大世界表中收入的购买力平价偏差，发现越穷的国家收入越被高估，导致国际收入不平等被严重低估；通过估计食品恩格尔曲线来测量偏差并给出修正后的收入数据。
Purchasing power–adjusted incomes applied in cross-country comparisons are measured with bias. This paper estimates the purchasing power parity (PPP) bias in Penn World Table incomes and provides corrected incomes. The bias is substantial and systematic: the poorer a country, the more its income tends to be overestimated. Consequently, international income inequality is substantially underestimated. The methodological contribution is to exploit the analogies between PPP bias and the bias in consumer price index (CPI) numbers. The PPP bias and subsequent corrected incomes are measured by estimating Engel curves for food, an established method of measuring CPI bias.