Social NetworksSocial Networks……through computer through computer

networks…networks…

Types of NetworkingTypes of Networking• Networking for a job…Networking for a job…• Networks of people trying to do a Networks of people trying to do a

tasktask• Networks of organizationsNetworks of organizations

– The third modeThe third mode•HierarchicalHierarchical•MarketMarket

Social NetworksSocial Networks• ““The term was first coined in 1954 by The term was first coined in 1954 by J. A. BarnesJ. A. Barnes (in: (in: Class and Class and

Committees in a Norwegian Island ParishCommittees in a Norwegian Island Parish, in Human Relations”), in Human Relations”)• Social Network growth 2004 through 2005 (in thousands):Social Network growth 2004 through 2005 (in thousands):

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MyspaceFacebookXangaBeboFriendsterTribe Net.LinkedinOrkut

……the growth is concealed by the growth is concealed by the big sites…the big sites…

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Tribe Net.LinkedinOrkut

Types of Social NetworksTypes of Social Networks• VRML WorldsVRML Worlds

– Avatara’s Home @ PointworldsAvatara’s Home @ Pointworlds• Game sitesGame sites

– Yahoo spadesYahoo spades– Star Wars GalaxiesStar Wars Galaxies

• BlogsBlogs– LivejournalLivejournal

• Career NetworkingCareer Networking– LinkedinLinkedin

• Friendship NetworkingFriendship Networking– FacebookFacebook

Contact networks of daily communications

Flickr network of 2367 Flickr network of 2367 peoplepeople (Flickr is a picture sharing (Flickr is a picture sharing system)system)

Indices (my selection)Indices (my selection)• BetweennessBetweenness

– An intermediary. The extent to which a node is directly connected only An intermediary. The extent to which a node is directly connected only to those other nodes that are not directly connected to each otherto those other nodes that are not directly connected to each other

• ClosenessCloseness– Measure of nearness to all other individualsMeasure of nearness to all other individuals

• DegreeDegree– Number of ties to other actorsNumber of ties to other actors

• RadialityRadiality– Content-focused. Quality of information passed throughContent-focused. Quality of information passed through

• Structural equivalenceStructural equivalence– Common set of linkages to same others. Also, being at the same level Common set of linkages to same others. Also, being at the same level

in the organizationin the organization• Structural holeStructural hole

– Lacking connections in the networkLacking connections in the network• HomophilyHomophily

– Degree to which people in a network are similar to each other Degree to which people in a network are similar to each other

Team Work / NewsminutesTeam Work / Newsminutes

Where does it end?Where does it end?