Fig 1.
Evolution and co-evolution of the academic social network and collaborative network.
The vertical axis shows the evolution of the academic social network and the collaborative network, with two different snapshots in time (top and bottom) for the purpose of illustration. The horizontal axis shows the co-evolution of both networks.
Fig 2.
Effects used in the three models.
Adapted from Stadtfeld et al [50]. The continuous arrows represent existing relationships at the start of this study; the dashed arrows represent new relationships created over the course of this study. For the cross-network effects, the difference between relationships in the two networks is represented by different colored arrows.
Fig 3.
Development of the academic social network and the collaborative network.
The top three figures, from left to right, visualize the development of the academic social network over time (i.e. from April 2017/2018 up to June 2019). The middle three figures, from left to right, visualize the development of the collaborative network—zooming in on the core of the network in the bottom three figures. The numbers in the top right corner of each figure represent the number of connections (total outdegree) in each figure.
Fig 4.
Development of the academic social network showing the seniority and country of each researcher.
Again, the top three figures, from left to right, visualize the development of the academic social network over time (i.e. from April 2017/2018 up to June 2019). The relationships of one anonymized, early-career researcher from the UK have been highlighted in the bottom three figures to better illustrate how researchers of different seniority and country get to know each other over time.
Table 1.
Descriptives for the evolution of both networks.
Table 2.
Correlations between the (out)degrees of the two networks, for the three time points separately.
Table 3.
Evolution and co-evolution of the academic social network and the collaborative network: Parameter estimates and standard errors of SIENA models.