Social Networks

DEFINITION A social network is a social structure made of actors, which are discrete individual, corporate or collective social units like persons or departments [19] that are tied by one or more specific types of relation or interdependency, such as financial exchange, friendship, membership in the same club, sending of messages, web links, disease transmission (epidemiology), or airline routes. The actors of a social network can have other attributes, but the focus of the social network view is on the properties of the relational systems themselves [19]. For many applications social networks are treated as graphs, with actors as nodes and ties as edges. A group is the finite set of actors the ties and properties of whom are to be observed and analysed. In order to define a group it is necessary to specify the network boundaries and the sampling. Subgroups consist of any subset of actors and the (possible) ties between them. The science of social networks utilizes methods from general network theory and studies real world networks as well as structurally similar subjects dealing e.g. with information networks or biological networks.