Fig. 7
From: Community evolution in patent networks: technological change and network dynamics
Central Nodes Distribution by Comparing the Community Mapping Method with the Betweenness Centrality Method. The x-axis indicates years from 1980 to 2004, and the y-axis indicates the nodes, i.e. IPC subclasses, ordered in IPC index. The community mapping is based on consecutive 10-year windows. Betweenness centrality values are calculated on 3-year aggregation period started with the same labeled year as the other method. Colored blocks indicate the central nodes in common and different between the two method, following the legend