Network
Analysis
by Barry Wellman
Three Ways to Look at Reality
 Categories
 All Possess One or More Properties as an Aggregate of Individuals
 Examples: Men, Developed Countries
 Groups
 (Almost) All Densely-Knit Within Tight Boundary
 Thought of as a Solitary Unit (Really a Special Network)
 Family, Workgroup, Community
 Networks
 Set of Connected Units: People, Organizations, Networks
 Can Belong to Multiple Networks
 Examples: Friendship, Organizational, Inter-, World-System, Internet
Nodes, Relationships & Ties
 Nodes: A Unit That Possibly is Connected
 Individuals, Households, Groups, Organizations, States
 Relationships (A Specific Type of Connection)
 Gives Emotional Support
 Sends Money To
 Attacks
 Ties (One or More Relationships)
 Friendship (with possibly many relationships)
A Network is More Than
The Sum of Its Ties
 A Network Consists of One or More Nodes
 Could be Persons, Organizations, Groups, Nations
 Connected by One or More Ties
 Could be One or More Relationships
 That Form Distinct, Analyzable Patterns
 Can Study Patterns of Relationships OR Ties
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Overview - Journals
 Wellman founded, Connections, 1977
 Informal journal: “Useful” articles, news, gossip, grants,
abstracts, book summaries
 Bill Richards, Tom Valente edit now
 Lin Freeman founded, Social Networks, 1978
 Formal journal: Refereed articles
 Ronald Breiger now co-editor
 David Krackhardt founded, J of Social Structure, 2000
 Online, Refereed
 Lots of visuals
 Articles Appear Occasionally when their time has come
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Overview – Key Books
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Elizabeth Bott, Family & Social Network, 1957
J. Clyde Mitchell, Networks, Norms & Institutions, 1973
Holland & Leinhardt, Perspectives on Social Network Research,1979
S. D. Berkowitz, An Introduction to Structural Analysis, 1982
Knoke & Kuklinski, Network Analysis, 1983
Charles Tilly, Big Structures, Large Processes, Huge Comparisons, 1984
David Knoke, Political Networks, 1990
John Scott, Social Network Analysis, 1991
Ron Burt, Structural Holes, 1992
Manuel Castells, The Rise of Network Society, 1996, 2000
Wasserman & Faust, Social Network Analysis, 1992
Nan Lin, Social Capital (monograph & reader), 2001
Monge & Contractor, Theories of Communication Networks, 2003
Overview – Software
1) UCINet – Whole Network Analysis
2) MultiNet – Whole Network Analysis
3) P*Star – Dyadic Analysis
4) Krackplot – Network Visualization
5) Pajek – Network Visualization
6) Personal Network Analysis
1) SPSS/SAS – See Wellman, et al. “How To…” papers
The Social Network Approach
 The world is composed of networks
- not densely-knit, tightly-bounded groups
 Networks provide flexible means of social organization
and of thinking about social organization
 Networks have emergent properties of structure and
composition
 Networks are a major source of social capital
mobilizable in themselves and from their contents
 Networks are self-shaping and reflexive
 Networks scale up to networks of networks
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Networked Individualism
 Moving from a society bound up in little boxes to a
multiple network – and networking – society
 Networks are a flexible means of social organization
 Networks are a major source of social capital:
mobilizable in themselves & from their contents
 Networks link:
 Persons
 Within organizations
 Between organizations and institutions
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Little Boxes
Glocalization
Networked Individualism
Barry Wellman co-editor
Social Structure:
A Network Approach
JAI-Elsevier Press 1998
Ways of Looking at Networks
 Whole Networks & Personal Networks
 Focus on the System or on the Set of Individuals
 Graphs & Matrices
 We dream in graphs
 We analyze in matrices
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Whole Social Networks
 Comprehensive Set of Role Relationships in a Full System
 Analyze Each Role Relationship – Can Combine
 Composition: % Women; Heterogeneity; % Weak Ties
 Structure: Pattern of Ties
 Village, Organization, Kinship, Enclaves, World-System
 Typical Methods: Cliques, Blocks, Centrality, Flows
 (1) What is the Real Structure of an Organization?
 (2) How Does Information Flow Through a Village?
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Duality of Persons & Groups
 People Link Groups
 Groups Link People
 An Interpersonal Net is an
Interorganizational Net
 Ronald Breiger 1973
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The Dualities of Persons and Groups -- Graphs
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Dualities of Persons and Groups -- Matrices
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Dualities of Persons and Groups: Event-Event Matrix
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Neat Whole Network Methods
 QAP
 Regression of Matrices
 Example: Co-Citation (Intellectual Tie)
Predicts Better than Friendship (Social Tie)
To Inter-Citation
 Clustering: High Density; Tight Boundaries (“Groups”)
 Block Modeling
 Similar Role Relationships, Not Necessarily Clusters
 Canada & Mexico in Same Block – US Dominated
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Erickson, 1988: From a Matrix > . . .
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. . . To a Block Model
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Costs of Whole Network Analysis
 Requires a Roster of Entire Population
 Requires (Imposition of) a Social Boundary
 This May Assume What You Want to Find
 Hard to Handle Missing Data
 Needs Special Analytic Packages
 Becoming Easier to Use
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Personal Social Networks
 Ptolemaic Ego-Centered View
 Good for Unbounded Networks
 Often Uses Survey Research
 Example:
 (1) Do Densely-Knit Networks Provide More Support? (structure)
 (2) Do More Central People Get More Support?(network)
 (2) Do Women Provide More Support? (composition)
 (3) Do Face-to-Face Ties Provide More Support Than Internet Ties? (relational)
 (4) Are People More Isolated Now? (ego)
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