Betweenness and Closeness - Indicators
Which node has power in a network?
"They say the golden rule in Real Estate is: Location, Location, Location. Might this rule also hold in social networks? In real estate, location is determined by geography - your physical location. In social networks, location is determined by your connections and the connections of those around you - your virtual location. Two social network measures, Betweenness and Closeness, are particularly revealing of a node's advantageous or constrained location in a network. The values of both metrics are dependent upon the pattern of connections that a node is embedded in. Betweenness measures the control a node has over what flows in the network - how often is this node on the path between other nodes? Closeness measures how easily a node can access what is available via the network - how quickly can this node reach all others in the network? A combination where a node has easy access to others, while controlling the access of other nodes in the network, reveals high informal power."
Betweenness as the most important metric of influence
"this research in ARVIX blog, Best Connected Individuals Are Not the Most Influential Spreaders in Social Networks suggests that a different way to measure the centrality might be more useful in determining how much throw weight a person actually has. Betweenness is a measure of how short are the chains that connects a person to the totality of the network. Like PageRank, betweenness is recursive: the people with the highest betweenness are likely to be connected to other people with high betweenness.
This means people are influential because they are connected to many influential people. But influence doesn’t seem directly linked to how many people you are connected to. It’s a function of being connected to others who have short chains to many other people with high betweenness. Or, looked at differently, betweenness is a measure of how many social circles, or social scenes, a person is connected to.
So, it’s not who you know: it’s where you know. It’s where you are situated in the network, and not just in the limited sense of how many immediate contacts you have." (http://www.stoweboyd.com/post/2093344403/content-context-conduit-its-not-who-you-know-but)