Interdicting Social Networks

Cpt Tobias Uwe Kuhn(Lt Paul Ortiz)

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Outline

• Introduction• Assumptions• Defining the Model• Scenarios 1 - 4• Conclusions

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Introduction

Show Video

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Question

http://www.casos.cs.cmu.edu/computational_tools/datasets/index.html

How can we interdict a social network by identifying potential detainees, such that a group as big as possible is separated.

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Assumptions

• Perfect knowledge about terrorists’ social network

• We cannot detain the ways of communication• We cannot detain bin Laden himself• We can detain everyone else (for now)

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Defining the Model

∞AIN AOUT

1 BIN BOUT

1

XIN XOUT

1 DIN DOUT

1

CIN COUT

1

∞ ∞

∞ ∞

∞

∞∞

A

X

B

D

C

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Defining the Model

AIN AOUT

1 BIN BOUT

1

XIN XOUT

1 DIN DOUT

1

CIN COUT

1

∞ ∞

∞ ∞

∞∞

∞∞

1

1

s

t

s-t cut

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First Run

Additional Constraint: Don’t use terrorist leader’s direct contacts as target nodes

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Scenario 1: biggest possible group

Result: Detain Wadih El Hage and Mohamed Owhali separates 12 terrorists from bin Laden.

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Scenario 2: maximal group size of 4

Result: Detain Khalfan Mohamed and Achmed Ghailani separates 4 terrorists from bin Laden.

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Scenario 3: El Hage, Owhali save

Result: Detain Khalfan Mohamed and Achmed Ghailani separates 4 terrorists from bin Laden. (Yes, it is the same as in the previous scenario.)

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Scenario 4: Commander briefing

• “I need to know: What are the groups we can separate and who do we have to detain for that!”

• Means all groups and detainees

Show in GAMS

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Conclusions

• This model can be used on any social network• It gives crucial information on how to separate

groups from the leader• Further research

– Limit number of potential detainees– Add costs/probabilities of detaining a terrorist– Weighted connections– …

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Questions?

• Other separated groups: