Fig. 1

Flow network of knowledge diaspora. Points on the circle indicate topics (fine-grained knowledge representations) that are colored according to their SCImago area (coarse-grained knowledge representations), represented by thick sectors, whose color legend is reported. Two topics are connected if at least one author at time τ switched from one to another 5 years later. a Flow of authors moving his/her research activity from one topic to others across time. b How to read this visualization: switches between topics of the same area, namely “intra-area flows”, are represented as ‘U” shaped links close to sectors, to distinguish them from “cross-area flows”. The outgoing flow is colored by the area of origin. The width of edges is proportional to the observed flow. See Appendix for more details about topics classification and this type of visualization