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Targeting Offenders and Network Analysis Presentation at the 62 nd Annual SPIAA Training Conference July 23, 2013. Ken Novak, Ph.D. Andrew Fox, Ph.D. University of Missouri – Kansas City. Overview of presentation. Social Network Analysis (SNA) What is it? Why does it matter?
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Targeting Offenders and Network AnalysisPresentation at the 62nd Annual SPIAA Training ConferenceJuly 23, 2013 Ken Novak, Ph.D. Andrew Fox, Ph.D. University of Missouri – Kansas City
Overview of presentation Social Network Analysis (SNA) • What is it? • Why does it matter? • How do you do that? • How can it help?
What is SNA? • Analysis of social relationships • Beyond individual attributes • Map relationships between individuals • Information and goods flow between people, so the structure of relationships matters • Through SNA we can identify important individuals based on their social position
Why does SNA matter? • Theoretical support • Provides ability to focus scarce resources • Effectiveness • Efficiency • Equity • Aid in developing intervention on violent groups
Why does theory matter? • Most effective policies are informed by theory • Theory-guided practice increases effectiveness • Understanding why something works/doesn’t work • Why does a strategy work here but not there? • Ensures application of strategy is tailored to environment • Effective crime prevention is not ‘off the shelf’
Behavior and control • Crime is concentrated among individuals • These individuals frequently interact with each other • Crime and attitudes toward crime are learned in intimate groups • Peer influence • Justification for offending • Peer association matters
Factors for learning crime* • Whom does a person associate? • Balance between individuals in the network • Transference of deviant norms within network • Quality/strength of relationships This makes connections within social networks important to understand *Learning / Differential Association
Behavior and control • Groups have the ability to regulate behavior • Groups have norms for behavior, and the ability to reward and sanction • Social control • Formal – police, courts, corrections • Informal – Peers, parents, community, clergy • Goal: identifying social networks and convincing them to ‘police themselves’
Analysis • Challenge: Identification of violent networks • Approach: Social Network Analysis (SNA) • Examination of social relationships • Understand flow of information • Identification of which individuals are most important in a network • “Leveraging” influence of these individual • Post-hoc investigations
What’s the point? • Converting data into intelligence DATA MODEL-ING INTELLIGENCE Input Analysis Output
Data (input) • Information that connects or informs the relationship between 2+ people • Field Interrogation Forms • Arrest Reports • Car/Traffic Stops • “Street intel” • Gang intelligence reports • NationalIntegrated Ballistic Information Network
Data (a word of caution) • Intelligence will only be as good as the data used • Flawed, incomplete, stale, cursory data yield similar output
Terms • Sociogram: A picture in which are represented as points in two-dimensional space. The relationships between two people are represented by a line or an arrow. Sociograms are also referred to as graphs or network maps. • Node: In a graph, nodes represent the actors or people and are generally represented by a circle. • Tie: The link between two nodes in a sociogram is referred to as a tie.
SNA for Dummies Node
SNA: Sociogram Node Tie
Understanding group dynamics… • Focus resources • Deterrence, levers to pull • Holding members accountable for each other’s actions • Understanding informal social control • Network structure, properties SNA is a tool to graphically display group dynamics
Colorado Springs Sexual Contact Network SOURCE: James Moody. http://www.soc.sbs.ohio-state.edu/jwm/
The 9-11 Hijacker Network SOURCE: Valdis Krebs http://www.orgnet.com/
Advantages of Using SNA • Layout optimization • No lines on top of each other, clear layout • Space on the page to equal social distance • Identifying key players • Centrality as a measure of importance • Free software (Pajek and Excel)
Field Interview FIF 1 100 Andrew Fox 200 Ken Novak Edge 100 200 Network Representation 200 100 FIF 2 200 Ken Novak 350 Joe McHale 400 Tiffany Gillespie 350 200 200 350 200 400 350 400 400 FIF 1 & 2 Combined 100 200 200 350 200 400 350 400 200 100 350 400
Step 2 – Individuals who were mentioned in the Step 1 FI Cards who had not previously been mentioned Step 0- Gang Member Information Cards (GMIC) FI Cards and GMIC Step 1 – Individuals who were mentioned in the Step 0 GMIC or FI Cards
Who is most central in the network? Three types of centrality: • Degree Centrality • 2. Betweenness Centrality • 3. Eigenvector Centrality
Degree Centrality – Simply the number of ties a node has in the network. Degree centrality suggests that those who have the most ties are the most central to the network.
Betweenness Centrality – Those who are the intersection on many paths between others.
Eigenvector Centrality – Those who are connected to many connected people
Major Findings • Social network analysis using FI cards confirms findings about gangs and offers new insights about gang social structure • High turnover of gang networks (80% less than 1 year) • The line between cliques is fuzzy, might be more hybrid gangs than previously thought • Betweenness centrality identifies those most likely to be arrested
Figure 4.9: 2007 network with clique affiliations Key: Varrio Sixty First = Red; West Side Grandel = Blue; Varrio Clavalito Park = Green
ATF / NIBIN IntelligenceNationalIntegrated Ballistic Information Network(these dots indicate linked gun crimes, yellow dots indicate cases involving homicides)
Training • Finding the right crime analysts • Giving them time and space to learn • Need to fully understand PD data systems and how to extract large amounts of data from those systems • Need to understand the concepts, not just the technique.
Thank YouQuestions?Contact information:Ken Novak; 816-235-1599; novakk@umkc.eduAndrew Fox; 816-235-5955; foxan@umkc.edu
Degree centrality Center for Violence Prevention and Community Safety
Betweenness centrality Center for Violence Prevention and Community Safety