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Events for April 30, 2013
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PhD Defense - Jason Tsai
Tue, Apr 30, 2013 @ 12:00 AM - 02:00 PM
Thomas Lord Department of Computer Science
University Calendar
Date: April 30, 2013
Venue: RTH 526
Time: 12:00pm
PhD Candidate: Jason Tsai
Title: Protecting Networks Against Diffusive Attacks: Game-Theoretic Resource Allocation for Contagion Mitigation
Committee:
Milind Tambe (chair)
Stacy Marsella
Bhaskar Krishnamachari
Sha Yang
Matthew McCubbins (outside member)
Emma Bowring
Abstract:
Many real-world situations involve attempts to spread influence through a social network. For example, viral marketing is when a marketer selects a few people to receive some initial advertisement in the hopes that these `seeds' will spread the news. Even peacekeeping operations in one area have been shown to have a contagious effect on the neighboring vicinity. Each of these domains also features multiple parties seeking to maximize or mitigate a contagious effect by spreading its own influence among a select few seeds, naturally yielding an adversarial resource allocation problem. My work models the interconnected network of people as a graph and develops algorithms to optimize resource allocation in these networked competitive contagion scenarios.
Game-theoretic resource allocation in the past has not considered domains with both a networked structure and contagion effects, rendering them unusable in critical domains such as rumor control, counterinsurgency, and crowd management. Networked domains without contagion effects already present computational challenges due to the large scale of the action space. To address this issue, my first contribution proposed efficient game-theoretic allocation algorithms for the graph-based urban road network domain. This work still provides the only polynomial-time algorithm for allocating vehicle checkpoints through a city, giving law enforcement officers an efficient tool to combat terrorists making their way to potential points of attack. Second, I have provided the first game-theoretic treatment for contagion mitigation in social networks and given practitioners the first principled techniques for such vital concerns as rumor control and counterinsurgency. Finally, I extended my work on game-theoretic contagion mitigation to address uncertainty about the network structure to find that, contrary to what evidence and intuition suggest, heuristic sampling approaches provide near-optimal solutions across a wide range of generative graph models and uncertainty models. Thus, despite extreme practical challenges in attaining accurate social network information, my techniques remain near-optimal across numerous forms of uncertainty in multiple synthetic and real-world graph structures.
Beyond optimization of resource allocation, I have further studied contagion effects to understand the effectiveness of such resources. First, I created an evacuation simulation, ESCAPES, to explore the interaction of pedestrian fear contagion and authority fear mitigation during an evacuation. Second, using this simulator, I have advanced the frontier in contagion modeling by developing empirical evaluation methods for comparing and calibrating computational contagion models that are critical in crowd simulations and evacuation modeling. Finally, I have also conducted an examination of agent-human emotional contagion to inform the rising use of simulations for personnel training in emotionally-charged situations.
Location: Ronald Tutor Hall of Engineering (RTH) - 526
Audiences: Everyone Is Invited
Contact: Lizsl De Leon
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Computer Science PhD Social Committee Lunch
Tue, Apr 30, 2013 @ 12:00 PM - 01:30 PM
Thomas Lord Department of Computer Science
Student Activity
Computer Science PhD Social Committee Lunch, for invited PhD Computer Science students.
Location: Annenberg School For Communication (ASC) - 104
Audiences: Everyone Is Invited
Contact: Assistant to CS chair
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Epstein Institute / ISE 651 Seminar Series
Tue, Apr 30, 2013 @ 03:45 PM - 05:00 PM
Daniel J. Epstein Department of Industrial and Systems Engineering
Conferences, Lectures, & Seminars
Speaker: Dan A. Iancu, Assistant Professor, Graduate School of Business, Stanford University
Talk Title: "Pareto Efficiency in Robust Optimization"
Series: Epstein Institute Seminar Series
Abstract: In this talk, we formalize and adapt the well-known concept of Pareto efficiency in the context of the popular robust optimization (RO) methodology. We argue that the classical RO paradigm need not produce solutions that possess the associated property of Pareto optimality, and illustrate via examples how this could lead to inefficiencies and sub-optimal performance in practice. We provide a basic theoretical characterization of Pareto robustly optimal (PRO) solutions, and extend the RO framework by proposing practical methods that verify Pareto optimality, and generate solutions that are PRO. Critically important, our methodology involves solving optimization problems that are of the same complexity as the underlying robust problems, hence the potential improvements from our framework come at essentially no computational cost. We perform numerical experiments drawn from three different application areas (portfolio optimization, inventory management, and project management), which demonstrate that PRO solutions have a significant upside compared with solutions obtained via classical RO methods, at no extra cost or downside. (Joint work with Nikolaos Trichakis from HBS)
Biography: Dan Iancu is an Assistant Professor of Operations, Information and Technology at Stanford Universityââ¬â¢s Graduate School of Business. Prior to joining the faculty at the Graduate School of Business, he spent one year as a Goldstine Fellow in the Risk Analytics Group at the IBM T.J. Watson Research Center. A native of Romania, Professor Iancu holds a BS degree in Electrical Engineering and Computer Science from Yale University (2004), an SM in Engineering Sciences from Harvard University (2006), and a PhD in Operations Research from the Sloan School of Management at the Massachusetts Institute of Technology (2010). He was the recipient of the Best Student Paper Prize of the INFORMS Optimization Society (2009), and of two teaching prizes, at Harvard and at MIT Sloan.
Professor Iancu's research is focused on problems at the interface of finance and operations that typically involve taking actions in rapidly changing environments, under high degrees of risk and uncertainty. His work deals with both the development of innovative algorithms and analytical support tools, as well as with understanding how these interact with business decision making. Specific applications include multiaccount portfolio optimization, strategic and tactical supply chain management, and dynamic pricing.
Host: Daniel J. Epstein Department of Industrial and Systems Engineering
More Information: Seminar-Iancu.doc
Location: Von Kleinsmid Center For International & Public Affairs (VKC) - Room 100
Audiences: Everyone Is Invited
Contact: Georgia Lum
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Study NightsTue, Apr 30, 2013 @ 07:00 PM - 10:00 PM
Viterbi School of Engineering Student Affairs
Workshops & Infosessions
Come out to Study Nights and conquer your procrastination!
Group Study Rooms to work with your peers, quiet study spaces available, tutors, coffee, tea and snacks.
Sponsored by The Center for Engineering Diversity and The Viterbi Academic Resource Center.
Need more information? E-mail viterbi.ced@usc.edu.Location: Grace Ford Salvatori Hall Of Letters, Arts & Sciences (GFS) - 111
Audiences: Everyone Is Invited
Contact: Center for Engineering Diversity
