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Chapter 7. Modelling relationships that change over time
Figure 7.1: Laplacian embedding of the Caviar network with undirected edges with
all time periods merged. Labels are individual identifiers, which range from 1 to 110.
the embedded graph, each participant appears 11 times; the time period follows the
node ID in parentheses. To have a clearer view of the node relationships, we do not
show the edges — in the embedding, distance reflects dissimilarity for all pairs of
nodes, whether they were originally connected or not. There are many participants
who are almost inactive in many time periods and so are clearly peripheral to the
structure of the network — their placement in the embedding is far from the origin,
so we omit them and show only the center part of the embedded graph.
Four important clusters are visible in Figure 7.3. The vertical arm corresponds
to the cocaine importation group with its key figure, N12. There is also a large
cluster that appears centrally, but actually goes back into the plane of the image in
a 3-dimensional representation; this is the hashish importation group with its key
Chapter 7. Modelling relationships that change over time
Figure 7.1: Laplacian embedding of the Caviar network with undirected edges with
all time periods merged. Labels are individual identifiers, which range from 1 to 110.
the embedded graph, each participant appears 11 times; the time period follows the
node ID in parentheses. To have a clearer view of the node relationships, we do not
show the edges — in the embedding, distance reflects dissimilarity for all pairs of
nodes, whether they were originally connected or not. There are many participants
who are almost inactive in many time periods and so are clearly peripheral to the
structure of the network — their placement in the embedding is far from the origin,
so we omit them and show only the center part of the embedded graph.
Four important clusters are visible in Figure 7.3. The vertical arm corresponds
to the cocaine importation group with its key figure, N12. There is also a large
cluster that appears centrally, but actually goes back into the plane of the image in
a 3-dimensional representation; this is the hashish importation group with its key