Loet Leydesdorff, Alexander Tekles, Lutz Bornmann
The disruption index (DI) based on bibliographic coupling and uncoupling between a document and its references was first proposed by Funk & Owen-Smith (2017) for citation relations among patents and then adapted for scholarly papers by Wu et al. (2019). However, Wu & Wu (2019) argued that this indicator would be inconsistent. We propose revised disruption indices (DI* and DI#) which make the indicator theoretically more robust and consistent. Along similar lines, Chen et al. (2020) developed the indicator into two dimensions: disruption and consolidation. We elaborate the improvements in simulations and empirically. The relations between disruption, consolidation, and bibliographic coupling are further specified. Bibliographic coupling of a focal paper with its cited references generates historical continuity. A two-dimensional framework is used to conceptualize dis-continuity not as a residual, but a dimension which can further be specified.