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www.QinetiQ.com
Social Network Analysis
Mark Round
+44 (0) 1684 89 4450
Date: 04 Dec 2007Location: BCS North London Branch
© Copyright QinetiQ
SNA Overview 5
Simplified SNA process
Collate Prepare Analyse Visualise Plan
& Collect
Interpret Advise
DYNAMICS:infer missing datawhy links formgrowth processesvulnerabilitiesrobustness
METRICS:central linkscentral actors roles & positionssubgroupscentralisation
INTEL & ADVICE:group structurelines of influencestabilisation pointsintervention pointsoptions
NETWORK MODEL
INFORMATION:Data mining resultsEntity extractionBayesian analysis
RAW DATA:interview datasurvey resultsobservationssystem logs
SOCIOGRAMS
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SNA Overview 6
• What are you trying to explain?
– variation in success, e.g. performance?
– homogeneity, in attitudes, beliefs or practices?
• Why does tie structure matter? Is it because they are:
– pipes, or
– girders
• What is the currency? Paperbacks, parcels, viruses, ideas, gossip?
– How does each diffuse: is it ‘copied’ or ‘moved’?
– What logic guides the routing of them?
Borgatti, S.P. & Foster, P.C. The Network Paradigm in Organizational Research: …. Journal of Management, 29(6) (2003) 991–1013
Borgatti, S.P., Centrality and Network Flow' Social Networks, 27, (2005) 55-71
Plan: What to ask before conducting an analysis
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SNA Overview 7
Collect
Collect/collate: relationships traced in system logs
ORGANISATIONAL DATA
called,
emailed,
sought help from,
invited,
met with,
shared a space with,
…
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SNA Overview 9
Data: QinetiQ info flow questionnaire
Caveat: Borgatti (2005) On the robustness of centrality measures under conditions of imperfect data, Social Networks, 28, 2
Analyse: betweenness (centrality) – I…
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SNA Overview 10
A B
DATA:
QinetiQ staff,Problem-Solving questionnaire
Analyse/Interpret: discovering brokers (boundary spanners)
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SNA Overview 11
Analyse: betweenness (centrality) – 7/7 attacks
Jordan, F. personal communication
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SNA Overview 12
m-slicing results:
Case Study:JFCOM MNE4 Week 1[Planning]
IWS m-slice 96:single network component
Components
Control
KnowledgeKnowledgeSupportSupport
Planning
Assessment
Execution
InteragencyInteragencyGroupGroup
Command
Interpret: structures & underlying processes
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SNA Overview 13
m-slicing results:
Case Study:JFCOM MNE4 Week 3 [Execution]
IWS m-slice 84:single network component
Components
Control
KnowledgeKnowledgeSupportSupport
Planning
Assessment
Execution
Command
Comp’ts integrated; Inter-agency distrib;WG appears; EBP still centralExecut’n on a limbMNIG gone native.
(but, caution…)
WG © Copyright QinetiQ
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SNA Overview 14
Collaboration tool logs, MNE4 Wk3 (link_wt>50)
IWS (blue), vs. random network (pink): ‘bimodal’ - suggests robustness to both
targeted attack & random failure
Degree Distribution (GT50, N=169)
0
10
20
30
40
50
60
70
80
6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96
Degree (upper bound)F
req
uen
cy
Interpret: Assessing robustness: JFCOM experiment: results
Robustness to targeted attack & random failure - rare
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SNA Overview 15
Removal of top 20% (degree) - small increase in diameter
Interpret/Advise: robustness - simulated attack
Collaboration tool logs (IWS/Wk3-GT50)
Simulated attack fails to disconnect network
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SNA Overview 16
• Difficulties in inferring causality – e.g. groups affect individuals, and vc. vs.
• Dynamic (predictive) modelling: statistical models, simulations
• Multi-modal networks (e.g. documents-people-groups-organisations)
• Missing data / overlapping networks (email vs. chat vs. observations)
• ‘Valued’ links – extracting value from weighted data
• Fragility & over-use of some measures
• Impact of spatial dimension
• Danger of cognitive bias in analysts
• Design and synthesis of networks
• (absence of a) Library of networks (network corpus), for ‘diagnosis’
• Analysis of very large networks
• Analysis tools are academic: powerful, borderline-usable, data formats…
Challenges & opportunities in SNA, in these domains
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SNA Overview 17Network analysis tools (yellow) and formats (blue) !
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