Why is an increase in income inequality often accompanied by an increase in socioeconomic segregation? And what are the welfare implications of this comovement? This paper uses a theoretical model to analyze the relationship between income inequality and socioeconomic segregation. It shows that rising inequality can trigger sorting according to income, as a monopolist's profits from offering sorting increase with income inequality. It also examines the relationship between sorting and social welfare and shows that profit-maximizing sorting patterns are not necessarily optimal from a welfare perspective. In fact, for a broad field of income distributions (monopolist) profits increase with inequality, while at the same time total welfare from sorting decreases.

中文翻译：

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排序、不平等和福利的垄断供给

为什么收入不平等的加剧往往伴随着社会经济隔离的加剧？这种联动对福利有什么影响？本文采用理论模型分析收入不平等与社会经济隔离的关系。它表明不平等加剧可以触发按收入排序，因为垄断者提供排序的利润随着收入不平等而增加。它还检查了排序与社会福利之间的关系，并表明从福利的角度来看，利润最大化的排序模式不一定是最优的。事实上，对于广泛的收入分配领域（垄断者），利润会随着不平等而增加，同时排序带来的总福利减少。