1. CRIM6660 Terrorist Networks Lesson 1: Introduction, Terms and Definitions

2. Course Overview Introductions Course and student expectations Review syllabus, reading and writing assignments Terms and Definitions

3. Networks

4. Basic Network Analysis Study of networks to determine structure and behavior Village survey – Who’s who? How are they connected? Why? Traffic analysis – What do the members of the network do? For whom? To whom? With whom? Why?

5. Basic Network Analysis Identify terrorist suspects Study their connections (physical & virtual) Study their daily activities Who they call, email Where they travel Who comes to visit with them locally Where they get money, ideas, materiel What they do with their money, ideas, materiel

6. Basic Network Analysis Individual motivations to join or leave a network? How can a network create its own motivations to join? How can a network become self-sustaining? What external factors can impact network expansion (or attrition)?

7. Basic Network Analysis A social relation is anything that links two people. Examples include: KinshipCo-membership FriendshipTalking with LoveHate ExchangeTrust CoauthorshipFighting

8. Basic Network Analysis Social Capital Trusted Handshake Trust propagation: An approach for inferring trust values in a network A user trusts some of his friends, his/her friends trust their friends and so on…

9. Basic Network Analysis Sources of Data can include: Interviews; newspaper articles; government reports; Congressional testimony; court records, proceedings; websites; social media accounts; intelligence reports Examples: Sageman, 2004; Qin et al, 2005

10. Basic Network Analysis We represent actors with points and relations with lines. Actors are referred to variously as: Nodes, Vertices, Actors or Points Relations are referred to variously as: Edges, Arcs, Lines, Ties Example: a b ce d

11. Basic Network Analysis Network analysis lets us answer questions like: Are unpopular kids more likely to become involved in terrorism than popular kids? Are people with weak ties more likely to become radicalized? Do central actors within a terrorist network control resources? What roles are certain members of a network most likely to embrace, and why? Do certain types of network relations predict future terrorist network leaders?

12. Basic Network Analysis Identifying prominent actors within the network Positional analysis; brokers Expert, authority Influencer Gatekeeper Coordinator Liaison Relational analysis / strength of ties

13. Basic Network Analysis Egocentric Networks : An individual and the set of people they have relations with. Measures: Similarity Size Types of relations Density Pattern of ties

14. Basic Network Analysis Sociocentric Networks: The connections among all members of a population. Measures: Network properties Density Sub-groups Positions

15. Terms & Definitions Node Should all “nodes” in a terrorist network be considered criminal? Clandestine/Dark Network Try to keep nodes and relations hidden Interactions, Relatedness, Roles, Cluster Strength vs. weakness of ties Position in a network

16. Terms & Definitions Node Degree - The degree of a node in a network is the number of connections it has to other nodes Average Degree - Average number of links per node (for measuring density, connectivity of network) Distance - The distance between two nodes is defined as the number of lines along the shortest path connecting them.

17. Terms & Definitions Directed Relation - An ordered pair of nodes that can be represented graphically as an arrow drawn between the nodes. Undirected Relation - Disregards any sense of direction and treats both nodes interchangeably. a b ce d Undirected, binary Directed, binary a b ce d a b ce d Undirected, Valued Directed, Valued a b ce d 13 4 2 1 In general, a relation can be: (1) Binary or Valued (2) Directed or Undirected

18. Basic Network Analysis Triads 16 possible combinations

19. Terms & Definitions Six degrees of separation Centrality measures importance of actors in a social network Degree Centrality Closeness Centrality Betweenness Centrality Eigenvector Stronger weights given to ties with central nodes than with peripheral nodes

20. Terms & Definitions Centrality - centrality refers to indicators which identify the most important vertices within a graph. Applications include identifying the most influential person(s) in a social network, key infrastructure nodes in the Internet or urban networks, and super spreaders of disease.

21. Centrality Degree Centrality – The number of direct connections a node has. What really matters is where those connections lead to and how they connect the otherwise unconnected.

22. Centrality Closeness Centrality - In connected graphs there is a natural distance metric between all pairs of nodes, defined by the length of their shortest paths. Thus, the more central a node is the lower its total distance to all other nodes.

23. Centrality Betweenness Centrality – Betweenness quantifies the number of times a node acts as a bridge along the shortest path between two other nodes. A node with high betweenness can have significant influence over how other nodes behave in the network (and serve as a potential single point of failure)

24. Centrality Eigenvector Centrality - Eigenvector centrality is a measure of the influence of a node in a network. It assigns relative scores to all nodes in the network based on the concept that connections to high- scoring nodes contribute more to the score of the node in question than equal connections to low-scoring nodes.

25. Social Network Analysis of 9/11 Terrorists Who are the key actors? Photographed in 2000 attending a meeting of known terrorists in Malaysia

26. Terrorist Network Analysis All 19 hijackers were within 2 steps (connections) of the 2 individuals photographed and considered potential terrorist suspects in 2000 Challenges include: Identifying nodes and relations prior to attack False positives / guilt by association Identifying any directional attributes of links When do you know you have “completed” the diagram of a covert network?

27. Social Network Analysis of 9/11 Terrorists Who are the key actors?

28. Exercise In the following sample network, identify which person could be eliminated from the network to cause the most damage (defined as loss of the most key knowledge source) Older veteran terrorists are colored red Middle aged veteran terrorists are colored yellow All other terrorists (presumably new or unknown status) are colored green Gray directed links (A -->B) indicate seeker of knowledge (A) and provider of knowledge (B) Hint: look for nodes with many arrows pointing at them

30. Answer The loss of person 46 has the greatest potential for knowledge loss. 90% of the network is within 3 steps of accessing this key knowledge source

31. Wrap-up Questions? Next week: Social Network Analysis Overview and demonstration Read assignment, come prepared with questions