Social Network Analysis:
Possibilities and Pitfalls
Dr Damon Alexander
School of Social and Political Sciences
University of Melbourne
Email: dta@unimelb.edu.au
The Power to Persuade Symposium
Melbourne
5 September 2012
Social Network Analysis (SNA) has an incredibly
diverse range of applications:
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Track down Saddam Hussein
Map terrorist networks
Examine spread of disease
Map social capital
Map childhood friendship
networks and how they change
• Map rise to power of Medici clan
in 14th century Florence
• Map friendship networks
between cows!
Basic Concepts
“A social network is a structure composed of a set of actors, some of whose
members are connected by a set of one or more relations.” (Knoke and
Yang, 2008)
Key building blocks are:
i) Actors (eg. individuals; organisations; nations)
ii) Relations (can be any form of interaction between two or more actors eg.
friendship network; kinship tie; advice network)
-Uses ‘relational’ data rather than individual attributes (eg. age; IQ)
-Structure/Agency Debate?
Network Types
i)
Complete Networks (‘whole’ or ‘global networks’)
- Includes all actors in a given population (eg. All service
providers in a service sector; all members of management team)
-Can analyse properties such as structure; composition; density
etc as well as properties of individuals in network
-Data can be difficult to collect
i)
Ego Networks (personal networks)
-Consist of one actor (ego) and all other actors (alters) directly
tied to ego.
-Can analyse and compare properties of ego’s ties but can’t make
assumptions about broader network.
-Data easier to collect
Example of ‘Complete Network’:
Melville Strategic Information Network
Example of ‘Ego Network’:
Melville Mayor (Strategic Information)
Data/Data Collection
Can use SNA to analyse any data with ‘relational’ form.
Examples:
– Survey/interview data collected through name generators/name
interpreters (who do you know…?) or contact matrices (how often
do you see…?)
– Documentary analysis (eg. Board directorships)
– Historical data (eg. John Padgett’s rise of the Medici clan)
– Analysis of group conversation based on video data.
– Analysis of passes between players on soccer team
– Analysis of links between political organisations based on
hyperlinks from website to website.
Measures/Tools for Analysis
Centrality
-In-Degree (measures ‘prominence’)
-Out-Degree (measures ‘influence’)
-Betweeness/Brokerage (measure extent of ‘connecting’ role)
Density (measures extent to which actors are connected within network)
External-Internal Index (measures ratio of in-group to out-group ties)
Reach (measures actors ‘reach’ across network)
*Can be used in conjunction with traditional quantitative measures
Project Examples
• Innovation Inside Government (Considine and Lewis)
– Mapped advice/strategic information networks in 11 local govts
• Social Connectivity Study (Considine, Lewis and Barraket)
– Mapped citizens economic, social and political support networks (ego)
• Primary Care Partnerships (Lewis and Baez)
– Mapped strategic advice networks across 2 PCPs.
• Crossing Boundaries (Alexander)
– Mapped ‘local action’ network in Buloke Shire
• DrinkWise (Lewis and Alexander)
– Mapped connections between board members and industry
• Climate change and health networks in Cambodia (Bowen et al)
– Mapping formal and informal partnership ties between organisations
Limitations/Pitfalls of SNA Research
i) Data Collection problems
ii) Clunky/cumbersome software
iii) Tendency to be overly descriptive (good at
what/when/where- less effective at how/why)
iv) Structure/agency problem (underplays agency)
*Works best with qualitative overlay
Resources:
Software:
• Ucinet for Windows: Software for Social Network Analysis. (Borgatti,
Everett and Freeman). (Includes NetDraw package) Free trial
software at: https://sites.google.com/site/ucinetsoftware/home
• Pajek (spider) by Vladimir Batagelj and Andrej Mrvar. Available for
free at: http://pajek.imfm.si/doku.php?id=pajek
Online Resources:
• International Network for Social Network Analysis (INSNA)
http://www.insna.org/
• Melnet http://www.sna.unimelb.edu.au/
Courses:
• Malcolm Alexander, ‘Introduction to Social Network Research and
Network Analysis’ (ACSPRI Short Course). Further information:
http://www.acspri.org.au/node/995
Further Reading:
• Knoke, D., and Yang, S., (2008). Social Network
Analysis. Thousand Oaks: SAGE Publications, Inc.
• Charles Kadushin (2012) Understanding Social
Networks: Concepts, Theories, and Findings. New York :
Oxford University Press
• Robert A. Hanneman and Mark Riddle (2005)
Introduction to Social Network Methods
http://faculty.ucr.edu/~hanneman/nettext/
• Granovetter, M. (1973) ‘The strength of weak ties’,
American Journal of Sociology, 78, pp. 1360-80.