The purpose of this paper is twofold. First, it introduces a novel inequality concept called income composition inequality, which describes how the composition of income in two sources, such as capital and labor income, varies across the income distribution. Second, it constructs an indicator for its measurement. This paper argues that the study of income composition inequality allows for: (i) a novel political economy analysis of the evolution of economic systems; and (ii) the technical assessment of the relationship between the functional and personal distributions of income. Following an empirical application, this paper discusses possible avenues for future research on the matter, ranging from development issues to public finance.

中文翻译：

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收入构成不平等

本文的目的是双重的。首先，它引入了一个新的不平等概念，称为收入构成不平等，它描述了资本和劳动收入等两种来源的收入构成如何随着收入分配而变化。其次，它为其测量构建了一个指标。本文认为，对收入构成不平等的研究允许：（i）对经济体系演变进行新的政治经济学分析；(ii) 对收入的功能分配和个人分配之间的关系进行技术评估。在实证应用之后，本文讨论了未来研究该问题的可能途径，从发展问题到公共财政。