Glossary of Network Terminology

Actor In an affiliation network, the people or other entities tied by events Asymmetrical tie An edge or relationship in a directed network that is not reciprocated; for example Bob cites Jane but Jane does not cite Bob Affiliation network A network where the edges consisted of a shared characteristic, such as attending a class together, rather than a direct relationship, such as friendship, and the nodes are the actors and events; actors cannot be directly tied to other actors, nor events to other events Attribute A characteristic of a node or edge; can be used to select nodes and edges or as an analytic variable; can also be represented visually through size, color, etc. Bipartite network A network where ties occur only between (and not within) two distinct subgroups; affiliation networks are a type of bipartite networks Betweenness centrality A type of node centrality measuring the importance of each node in geodesic paths between other nodes Centralization A network statistic measuring how unevenly spread the edges in a network are; a network with high centralization has relatively few key nodes connecting a large number of other nodes Clique A subgroup of nodes where each node shares an edge with every other node; the most restrictive subgroup definition Closeness centrality A type of node centrality determined by the geodesic distance to all other nodes in a component; high closeness indicates that most other nodes can be reached in relatively few steps