A measure of similarity between scientific journals and of diversity of a list of publications

The aim of this note is to propose a definition of the scientific diversity and corollarly, a measure of the ''interdisciplinarity'' of collaborations. With respect to previous studies, the proposed approach consists of 2 steps : first, the definition of similarity between journals and second, these similarities are used to characterize the homogeneity (or, on the contrary the diversity) of a publication list (that can be for one individual or a team)