In this paper two innovative procedures for the decomposition of the Pietra index are proposed. The first one allows the decomposition by sources, while the second one provides the decomposition by subpopulations. As special case of the latter procedure, the “classical” decomposition in two components (within and between) can be easily obtained. A remarkable feature of both the proposed procedures is that they permit the assessment of the contribution to the Pietra index at the smallest possible level: each source for the first one and each subpopulation for the second one. To highlight the usefulness of these procedures, two applications are provided regarding Italian professional football (soccer) teams.

本文提出了两种创新的Pietra指数分解程序。第一个允许按来源分解，而第二个允许按子种群分解。作为后一种过程的特殊情况，可以很容易地获得两个组成部分（内部和之间）的“经典”分解。这两个建议程序的一个显着特征是，它们允许以最小可能的水平评估对Pietra指数的贡献：第一个的每个来源和第二个的每个子种群。为了突出这些程序的实用性，提供了有关意大利职业足球（足球）队的两个应用程序。