Polarization of opportunity
提出了机会极化（POp）概念，衡量不同环境因素如何造成不公平的不平等，并用美国数据展示收入极化和机会不平等上升，但机会极化下降。
We introduce the concept of polarization of opportunities (POp) to explore how various circumstances shape unfair inequalities. While conventional measures of inequality of opportunity (IOp) focus on outcome disparities linked to factors such as race or gender, they do not account for how these circumstances group individuals into relatively uniform clusters. POp fills this gap by examining both the influence of circumstances and their role in clustering individuals into distinct poles. Using U.S. data, our analysis shows that while income polarization and IOp have risen over time, POp has decreased.