Diversity and Network Coherence as indicators of interdisciplinarity: case studies in bionanoscience

Ismael Rafols adn Martin Meyer
The multidimensional character and inherent conflict with categorisation of
interdisciplinarity makes its mapping and evaluation a challenging task. We propose a
conceptual framework that aims to capture interdisciplinarity in the wider sense of
knowledge integration, by exploring the concepts of diversity and coherence. Disciplinary
diversity indicators are developed to describe the heterogeneity of a bibliometric set
viewed from predefined categories, i.e. using a top-down approach that locates the set on
the global map of science. Network coherence indicators are constructed to measure the
intensity of similarity relations within a bibliometric set, i.e. using a bottom-up approach,
which reveals the structural consistency of the publications network. We carry out case
studies on individual articles in bionanoscience to illustrate how these two perspectives
identify different aspects of interdisciplinarity: disciplinary diversity indicates the largescale
breadth of the knowledge base of a publication; network coherence reflects the
novelty of its knowledge integration. We suggest that the combination of these two
approaches may be useful for comparative studies of emergent scientific and technological
fields, where new and controversial categorisations are accompanied by equally contested
claims of novelty and interdisciplinarity.