Figure 2

Statistics of the shipping routes. The left plot shows a histogram of the length of routes in terms of the number of edges. Most routes have length less than 10, but some visit as many as 30 ports. The middle plot shows the degree of a node (horizontal axis) against the number of routes the node appears in (vertical axis). The degree of a node in the path graph correlates with the number of routes it participates in and most nodes appear in a few routes, while some appear in more than 200. The right plot shows the estimated edge capacity in TEU (horizontal) against the number of routes in which each edge appears. Most edges appear in only a handful of routes, while few appear in nearly 100, and TEU capacity spans multiple orders of magnitude and correlates with the number of routes in which a port appears