Social Networks

Networks abound our routine vocabulary today. We use them often without realizing what all they encompass. I believe people use 'networks' to refer to social networks. A social network implies connections between individuals. One's social network includes family, friends, acquaintances, colleagues and people one communicates or exchanges information with.

Two key ideas associated with social networks are network density and network diversity. Network density depends on how closely knit a network is i.e. how well connected people are within a network. For example do all the people in your social network know each other. The larger the number of linkages within a network the higher its density. Diversity deals with heterogeneity of actors in a network. A family network is homogeneous on lines of kinship but heterogeneous in terms of age, gender and may be income/education levels. On the other hand a church group is homogeneous on lines of religion but heterogeneous in terms of age, gender, race, income, education etc.

Network density and diversity are key characteristics of a social network. They can help one predict the flow of information within a network. A dense homogeneous network is not well suited to acquiring information. Studies have shown that people get job information through weak ties as opposed to strong ties. A weak tie is a link such as an acquaintance or someone you know through someone else and not directly. The reason for this lies in the observation that information becomes redundant in a dense homogeneous network. One hears about the same things from different people over and over again. On the contrary a less dense and heterogeneous network links one to other networks. These weak links bring in information external to one's immediate network.

Social networks are of interest for many reasons. They can be used for targeted marketing, political campaigns, control of disease ad in general spread of information. Lately, terrorist networks have been studied to identify key actors and gauge how best to disable or breakdown the network.