Loet Leydesdorff, interdisciplinarity, and diversity

Diversity, as used in interdisciplinarity studies, has three components: variety, evenness, and dissimilarity. In 2019, Leydesdorff, Wagner, and Bornmann proposed an indicator, denoted as DIV*, that independently operationalized these three components and then combined them. Gini evenness is one factor in this formula. An important point is that Leydesdorff and his colleagues rejected so-called dual concepts, i.e. concepts that mix or are influenced by at least two of the three basic components of diversity. A few years ago Chao and Ricotta took a new look at “evenness” and showed that the Gini evenness measure, as well as the Lorenz curve, are dual concepts as they are influenced by variety. For this reason, I propose to replace the Gini evenness measure in DIV* with an evenness measure, actually an evenness profile, that is not influenced by variety.