Societal Poverty: A Relative and Relevant Measure
提出一个社会贫困线，基于各国贫困线数据，结合固定底线和收入中位数的相对比例，更贴近各国对贫困的实际定义，并发现1990年以来社会贫困下降速度远慢于绝对极端贫困。
Abstract Poverty lines are typically higher in richer countries, and lower in poorer ones, reflecting the relative nature of national assessments of who is considered poor. In many high-income countries, poverty lines are explicitly relative, set as a share of mean or median income. Despite systematic variation in how countries define poverty, global poverty counts are based on fixed-value lines. To reflect national assessments of poverty in a global headcount of poverty, this paper proposes a societal poverty line. The proposed societal poverty line is derived from 699 harmonized national poverty lines, has an intercept of $1 per day and a relative gradient of 50 percent of median national income or consumption. The societal poverty line is more closely aligned with national definitions of poverty than other proposed relative lines. By this relative measure, societal poverty has fallen steadily since 1990, but at a much slower pace than absolute extreme poverty.