Figure 1
From: Core and periphery structures in protein interaction networks
A sample network including three core/periphery structures, which are denoted by the gray circles (1–3). The empty cycle nodes are core members. The black and grey nodes represent 1-peripheries and 2-peripheries, respectively. Labelled nodes (A-F) are different types of 1-peripheries: A) the closed single-core periphery; B) the multiple-core periphery; C) the complete-open single-core periphery; D) the limited-open single-core periphery; both E) and F) the core-member periphery.