Journal of Development Economics · 2026 · [{"name": "Lant Pritchett", "affiliation": []}, {"name": "Martina Viarengo", "affiliation": []}]
中文摘要
联合国 2015 年可持续发展目标的第一项是：“在全世界消除一切形式的贫困。”这一宽泛目标意味着存在一系列贫困线，由此引出全球贫困线适当下界与上界的问题。“每天一美元”贫困线（按通胀更新为 2017 年购买力平价下的 P$2.15）被广泛接受为全球下界贫困线（GLBPL）。然而，尽管不同国家、组织和作者采用更高的贫困线，对于全球上界贫困线（GUBPL）却尚无共识。我们采用两种概念上截然不同的方法来估计 GUBPL，二者均植根于贫困测度的聚焦公理与标准经济学社会福利测度之间的张力。我们将候选 GUBPL 设定为：(i) 与实现充分物质福祉相一致的消费水平，或 (ii) 边际效用“足够接近”零的消费水平。无论采用哪一种方法，基于一系列福祉测度的实证结果均表明，包括世界银行报告的最高贫困线 P$6.85 在内的临时性贫困线都过低，难以成为 GUBPL 的合理候选。将这两种方法应用于四个不同的福祉指标，所有实证结果均表明 GUBPL 至少为 P$21.5，是标准 GLBPL P$2.15 的十倍。同时使用全球贫困线的下界与上界，可在“每天一美元”标准的极端排他性与同样极端包容的 GUBPL 之间取得平衡：前者将物质福祉水平极低、因而收入边际效用极高的人群归类为“非贫困”，后者则只把在全球范围内物质成就较高、收入边际效用较低（或较低一些）的人计为“非贫困”。
Abstract
The first of the United Nations 2015 Sustainable Development Goals is: “End poverty in all its forms everywhere.” An implication of this broad goal is the existence of an array of poverty lines, which raises the question of an appropriate lower-bound and an upper-bound to global poverty lines. The ‘dollar-a-day’ poverty line (updated for inflation to P$2.15 in 2017 PPP) is widely accepted as a global lower-bound poverty line (GLBPL). However, while different countries, organizations, and authors use higher poverty lines, there is no consensus on a global upper bound poverty line (GUBPL). We estimate a GUBPL using two conceptually distinct approaches, both grounded in the tension between the focus axiom for poverty measures and standard economic social welfare measures. We set a candidate GUBPL either at: (i) the consumption consistent with the achievement of adequate material well-being or (ii) the consumption level where marginal utility is “near enough” zero. Using either approach, empirical results across an array of measures of well-being demonstrate that ad hoc poverty lines, including the World Bank's highest reported poverty line of P$6.85, are far too low to be plausible candidates for a GUBPL. Using the two approaches across four distinct indicators of well-being all of the empirical results suggest a GUBPL of at least P$21.5, ten times higher than the standard GLPBL of P$2.15. The use of both a lower bound and upper bound global poverty line balances the radically exclusive nature of the ‘dollar-a-day’ standard, which classifies people with very low levels of material well-being and hence very high marginal utility of income as “not poor” with an equally radically inclusive GUBPL which counts only those with globally high material achievement and low (ish) marginal utility of income as “not poor.”