and $\alpha=15$. A visual inspection shows that the patterns are rather robust versus $\alpha$ and that $\alpha=10$ corresponds to an intermediate situation displaying interesting patterns.

Spatial pattern of the most central edges
-----------------------------------------

Instead of the most central nodes, we can also represent the most central edges such that their centrality is $g_e>\max{g_e}/\alpha$. If we consider here $\alpha=20$ we obtain for the different dates the results presented in Fig. \[fig:ebc\].

We can see that the pattern for the edges is naturally consistent with the one obtained with the node centrality.

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