Fig. 2: Conceptualisation and quantification of bilateral distances using the Jaccard distance.
From: The altering landscape of US–China science collaboration: from convergence to divergence
Focusing on a specific country pair, X and Y, the Collaboration Distance (\({D}_{{\rm{XY}}}\)) decreases as the number of coauthored works produced by researchers affiliated with institutions in these countries increases, and increases as the number of such collaborations decreases (see diagrams (a) vs. (b)). Considering another country, X’, if the number of coauthored works between X and Y is the same as that between X’ and Y, but the number of works produced by X is greater than that of X’, then \({D}_{{\rm{XY}}}\) will be larger than \({D}_{{{\text{X'}}}{\rm{Y}}}\). (see diagrams (b) vs. (c)). Based on this formulation, it is conceptualised that countries tend to converge when their distance decreases, and diverge when their distance increases (diagram (d)).
