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Dr. Axtell Friday Colloquium speaker

The Research Colloquium on Computational Social Science/Data Sciences speaker for Friday, November 01, 2019, will be Robert Axtell, Professor, Department of Computational and Data Sciences. Dr. Axtell’s talk entitled “Working with Heavy-Tailed Data: A Tutorial” will begin at 3:00 in the Center for Social Complexity Suite located on the 3rd floor of Research Hall.  The talk will be followed by a Q&A session along with light refreshments. 

This session will be live-streamed on the YouTube channel:  https://www.youtube.com/channel/UC7YCR-pBTZ_9865orDNVHNA

For announcements regarding this and future streams, please join the CSS/CDS student and alumni Facebook group: https://www.facebook.com/groups/257383120973297/

 For a list of upcoming and previous seminars, please visit:  https://cos.gmu.edu/cds/calendar/

 

Abstract:  This will be a hands-on talk in which Dr. Axtell will illustrate challenges and pitfalls of manipulating and statistically describing data which are extremely skew and possibly large in quantity. Motivated mainly by models from economics (e.g., firms and cities) and finance, datasets with millions of observations, both continuous and discrete, will be analyzed and plotted, with and without binning. There will be some discussion of parameter estimation but this will not be the primary focus of the talk. Heavy-tailed size distributions, the corresponding weighted-distributions, and the related ideas of moment distributions and size-biased sampling will all be discussed. Terminology such as ‘scaling’ and ‘scale-free’ will be unpacked and illustrated. The relation of Zipf-style rank-size plots to probability distributions will be developed. The competition between power law and lognormal distributions to represent heavy-tailed data will be addressed, including the ability of the lognormal to mimic a power law. Finite size effects and truncated distributions will also be discussed.

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Katherine Anderson, University of Pittsburgh,

will be the presenter at this Friday’s Research Colloquium on Computational Social Science/Data Science. Dr. Anderson is a visiting assistant professor at the University of Pittsburgh’s Department of Informatics and Networked Systems in the School of Computing and Information. She uses the tools of network analysis and computational modeling to look at how skills and ideas interact in collaborative environments.

Her talk entitled “Skill Networks and Measures of Complex Human Capital” will begin at 3:00 in the Center for Social Complexity Suite located on the 3rd floor of Research Hall.  The talk will be followed by a Q&A session along with light refreshments. 

For a list of upcoming and previous seminars, please visit:  https://cos.gmu.edu/cds/calendar/

 Abstract:  The relationship between worker skills and wages is a problem of tremendous economic interest, making it critical to have effective measures of the skills, knowledge, and experience that a worker brings to production: a bundle of worker characteristics that economists refer to as human capital. Traditional models of human capital measures either divide workers into broad categories (e.g., laborers and management) or treat skills as a uni-dimensional measure of speed, education, or experience. However, in knowledge based production, the value a worker brings to production depends on both her individual skills and the interaction between them. Here, I present a network-based method for characterizing worker skills. I construct a human capital network, in which nodes are skills and two skills are connected if a worker has both or both are required for the same job. A worker’s human capital can be measured according to the position of her skills on the network. I illustrate this method using a novel dataset, gathered from an online freelance labor market. I show that workers with diverse skills earn higher wages than their peers with more specialized skills, and that those who use their diverse skills in combination earn the highest wages of all. I also show that network-based measures of human capital capture variation in wages beyond that captured by the skills individually. Finally, I will show how these same techniques can be used outside of the economic context, to quantify the relationship between the skills of collaborators.

  

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Fahad Aloraini, CSS PhD Student, to present at Friday Colloquium

The Research Colloquium on Computational Social Science/Data Sciences speakers for Friday, October 18, 2019, will be Fahad Aloraini, Computational Social Science PhD student.  Fahad’s talk entitled “Modeling Solar-Panel Technology Adoption in Austin:  A Test of the Power of Integrating GIS and Cognitive Modeling” will begin at 3:00 in the Center for Social Complexity Suite located on the 3rd floor of Research Hall. The talk will be followed by a Q&A session along with light refreshments. 

This session will be live-streamed on the YouTube channel: https://www.youtube.com/channel/UC7YCR-pBTZ_9865orDNVHNA

For announcements regarding this and future streams, please join the CSS/CDS student and alumni Facebook group: https://www.facebook.com/groups/257383120973297/

For a list of upcoming and previous seminars, please visit: https://cos.gmu.edu/cds/calendar/

Abstract:  Agent-based models are being created by researchers from increasingly diverse fields. While this wealth of different perspectives enriches the subject of these models, it nevertheless poses problems and challenges such as the depth of knowledge required to construct these models — an aspect where diversity is an issue is agent-decision-making. While there are cognitive architectures that have been validated in lab conditions against human data, they are too computationally expensive to be used for agent-based models with even a moderate number of agents. Moreover, these cognitive architectures do not specify the way to construct the environment and do not leverage the power of agent-based models. As part of my master’s project I have come up with a framework that solves these issues:  The Objects Memory Dynamics and Actions framework. The framework moves away from the use of unreliable subjective data (surveys and self-reports) to more objective forms of data (rate of exposure to objects). The framework integrates two cognitive architectures (ACT-R and Fast and Frugal) to include a computationally efficient agent.  It specifies the objective data needed for agent learning and decision-making and how to estimate the unique rate at which an agent is exposed to an object in the environment. To test the framework, I model Solar-Panel Technology adoption of households in Austin, Texas, and compare it to work done in the field.

 

 

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Dr. Neil Johnson on “Slaying the Online Hydra of Hate, Distrust and Anti-Science”

The Research Colloquium on Computational Social Science/Data Sciences speaker for Friday, October 11, 2019, will be Neil Johnson, Professor of Physics, George Washington University. Dr. Johnson’s talk entitled “Slaying the Online Hydra of Hate, Distrust and Anti-Science” will begin at 3:00 in the Center for Social Complexity Suite located on the 3rd floor of Research Hall.  The talk will be followed by a Q&A session along with light refreshments. 

This session will be live-streamed on the YouTube channel:  https://www.youtube.com/channel/UC7YCR-pBTZ_9865orDNVHNA

For announcements regarding this and future streams, please join the CSS/CDS student and alumni Facebook group: https://www.facebook.com/groups/257383120973297/

 For a list of upcoming and previous seminars, please visit:  https://cos.gmu.edu/cds/calendar/

 Abstract:  Hate and distrust are thriving on the Internet [1]. In addition to the political world, medicine and science are also under attack. Social media platforms such as Facebook have access to state-of-the-art software tools, yet appear unable to keep it under control. In this talk, I discuss why this might be using a simple theory of the functional properties of networks-of-networks. I also show how the ’sociophysics’ of heterogeneous objects offers a fresh understanding of such systems as interacting gels in a multi-dimensional space. I then discuss how this analysis is connected to the unexpected surge in online pro-ISIS support that arose several years ago [2].
[1] N.F. Johnson et al., Hidden resilience and adaptive dynamics of the global online hate ecology, Nature, Sept. 12, 2019

[2] N.F. Johnson et al., New online ecology of adversarial aggregates: ISIS and beyond, Science 352, 1459 (2016)

Bio:  Neil Johnson is a professor of physics at George Washington University and heads up a new initiative in Complexity and Data Science which combines cross-disciplinary fundamental research with data science to attack complex real-world problems. He is a core member of GW’s new Knight Foundation-funded Institute for Data, Democracy and Politics. His research interests lie in the broad area of Complex Systems and ‘many-body’ out-of-equilibrium systems of collections of objects, ranging from crowds of particles to crowds of people and from environments as distinct as quantum information processing in nanostructures through to the online world of collective behavior on social media. He is a Fellow of the American Physical Society (APS) and is the recipient of the 2018 Burton Award from the APS. He received his BA/MA from St. John’s College, Cambridge, University of Cambridge and his Ph.D. as a Kennedy Scholar from Harvard University. He was a Research Fellow at the University of Cambridge, and later a Professor of Physics at the University of Oxford until 2007, having joined the faculty in 1992. Following a period as Professor of Physics at the University of Miami, he was appointed Professor of Physics at George Washington University in 2018. He presented the Royal Institution Christmas Lectures “Arrows of Time” on BBC TV in 1999. He co-founded and co-directed CABDyN (Complex Agent-Based Dynamical Systems) which is Oxford University’s interdisciplinary research center in Complexity Science, and an Oxford University interdisciplinary research center in financial complexity (OCCF).

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GMU CSS PhD Students to Present

The Research Colloquium on Computational Social Science/Data Sciences speakers for Friday, October 04, 2019, will be Amira Al-Khulaidy and Valentin Vergara, CSS PhD students. Their talk, entitled “Corruption and the effects of influence within social networks: An agent-based model of the “Lava Jato” scandal,” will begin at 3:00 in the Center for Social Complexity Suite located on the 3rd floor of Research Hall. The talk will be followed by a Q&A session along with light refreshments.

This session will not be video-streamed.

For announcements regarding future streams, please join the CSS/CDS student and alumni Facebook group: https://www.facebook.com/groups/257383120973297/

For a list of upcoming and previous seminars, please visit: https://cos.gmu.edu/cds/calendar/

We hope to see you on Friday, October 04, 2019 at 3PM.

Abstract: Corruption, and more specifically corruption in Latin America, is a complex phenomenon which is affected by politics, social structures and institutions, as well as individual behaviors. The Lava Jato is a large-scale example of corruption in Brazil. As of early 2019, there is still an ongoing investigation surrounding what has been lauded as the largest corruption scheme in Latin America. Advances in data analysis, computation, and social networks have allowed progress to be made with these types of investigations. The Lava Jato case has been a clear example of how breaking up social networks and understanding the extent of crime and individual corruption has revealed webs of corruption that have influenced politics, as well as hindered economic developed in Brazil. The several layers of interactions between individuals and institutions can be difficult to grasp and understanding the patterns and relationships within complex large-scale phenomena, such as corruption can seem impossible. Agent-based models can help with understanding these complex behaviors and systems. By capturing the patterns and gaining a better understanding of how corruption emerges and is manifested, we can help inform policy, as well as create better tools and methods for crime prevention and detection.

Bios:
Amira Al-Khulaidy – Computational Social Science PhD student, MEd. in Education, University of Virginia.
Valentin Vergara – Computational Social Science PhD student, MSc. Natural Resource Economics, Universidad de Concepción, Chile.

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Dr. Anamaria Berea to speak at Friday Colloquium

The Research Colloquium on Computational Social Science/Data Sciences speaker for Friday, September 27, 2019, will be Anamaria Berea, Visiting Research Assistant Professor, Complex Adaptive Systems Lab, University of Central Florida. Dr. Berea’s talk entitled “Exploring what is universally possible for life with a wealth of computational methods” will begin at 3:00 in the Center for Social Complexity Suite located on the 3rd floor of Research Hall. The talk will be followed by a Q&A session along with light refreshments.

This session will be live-streamed on the YouTube channel: https://www.youtube.com/channel/UC7YCR-pBTZ_9865orDNVHNA
For announcements regarding this and future streams, please join the CSS/CDS student and alumni Facebook group: https://www.facebook.com/groups/257383120973297/
For a list of upcoming and previous seminars, please visit: https://cos.gmu.edu/cds/calendar/

We hope to see you on Friday, September 27, 2019 at 3:00.

Abstract: In this talk I will discuss the advances made at NASA/SETI Frontier Development Lab AI Research Accelerator with respect to understanding the coevolution of biospheres and atmospheres, from cellular metabolisms to planetary environments. The current challenge presented by the sample of 1 when we consider the evidence of life and living systems in the Universe is overcome by a series of computer simulations and simulated data that give enough potential combinations of stable biospheres to be explored by machine learning algorithms. While we are only scratching the surface now with respect to the promise and perils of constructing well informed simulations and feeding them into more advanced algorithms, this approach will hopefully help identify possible life on observable exoplanets identified in the Kepler and TESS data. Methodologically, we explored Monte Carlo simulations, agent-based models, machine learning and dockerization in a complex data architecture supported by Google, in order to simulate more than 250,000 stable atmospheres, 500 types of synthetic genomes (metabolic networks) and more than 37,700,000 chemical reactions.

Bio: Anamaria Berea has dual PhDs in economics (2010) and computational social science (2012). Her research is focused on the emergence of communication in biological and social networks, by applying theories and methods from economics, complex systems and information theory to understand fundamental aspects of communication from cells to societies. Dr. Berea was one of the data scientists part of the NASA/SETI Frontier Development Lab (2017) in the heliophysics team and a data science mentor for the astrobiology team in the following year. She is the author of the book “Emergence of Communication in Socio-Biological Networks”, Springer, 2018. She is currently a Blue Marble Space Institute of Science research scientist and a Visiting Research Assistant Professor, Complex Adaptive Systems Lab, University of Central Florida.

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Dr. Sokolov to present at 9/20 colloquium

Dr. Vadim Sokolov, Assistant Professor, Department of Systems Engineering and Operations Research, will be the presenter at Friday’s
Research Colloquium on Computational Social Science/Data Science. His topic will be “Dimensionality Reduction for Agent Based Models.”

Friday, September 20, 3:00 p.m.
Center for Social Complexity Suite, 3rd Floor Research Hall

All are welcome to attend.

Abstract:
Bayesian algorithms such as Markov Chain Monte Carlo or Bayesian optimization can quickly become computationally prohibitive or even infeasible for high dimensional ABM problems. In many applications, however, the underlying dynamics of an ABM typically can be represented in a lower dimensional space. We will review existing linear and nonlinear dimensionality reduction methods, such as Laplacian eigenmaps and restricted Boltzmann machines. Further, we will present some new results for nonlinear dimensionality techniques based on deep learning models. We will demonstrate our approach in the context of Bayesian optimization algorithms applied to a transportation agent-based model. Finally, we discuss directions for future research.

Bio:

Vadim Sokolov is an assistant professor in the Systems Engineering and Operations Research Department at George Mason University. He works on building robust solutions for large scale complex system analysis, at the interface of simulation-based modeling and statistics. This involves, developing new methodologies that rely on deep learning, Bayesian analysis of time series data, design of computational experiments and development of open-source software that implements those methodologies. Inspired by an interest in urban systems he co-developed mobility simulator called Polaris that is currently used for large scale transportation networks analysis by both local and federal governments. Prior to joining GMU he was a principal computational scientist at Argonne National Laboratory, a fellow at the Computation Institute at the University of Chicago and lecturer at the Master of Science in Analytics program at the University of Chicago.

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McEligot to present on coastal flooding disasters

The Research Colloquium on Computational Social Science/Data Science speaker for Friday, September 13, will be Kim McEligot, Ph.D. Candidate, Department of Systems Engineering and Operations Research at George Mason University. Kim’s talk entitled “Sea Bright, New Jersey Reconstructed: Agent-Based Protection Theory Model Responses to Hurricane Sandy” (abstract below) will begin at 3:00 in the Center for Social Complexity Suite (373-381) located on the 3rd floor of Research Hall. The talk will be followed by a Q&A session along with light refreshments.

This session will be live-streamed on the YouTube channel: https://www.youtube.com/channel/UC7YCR-pBTZ_9865orDNVHNA
For announcements regarding this and future streams, please join the CSS/CDS student and alumni Facebook group: https://www.facebook.com/groups/257383120973297/

For a list of upcoming and previous seminars, please visit: https://cos.gmu.edu/cds/calendar/

Abstract: Coastal flooding is the most expensive type of natural disaster in the United States. Policy initiatives to mitigate the effects of these events are dependent upon understanding flood victim responses at an individual and municipal level. Agent-Based Modeling (ABM) is an effective tool for analyzing community-wide responses to natural disaster, but the quality of the ABM’s performance is often challenging to determine. This paper discusses the complexity of the Protective Action Decision Model (PADM) and Protection Motivation Theory (PMT) for human decision making regarding hazard mitigations. A combined (PADM/PMT) model is developed and integrated into the MASON modeling framework. The ABM implements a hind-cast of Hurricane Sandy’s damage to Sea Bright, NJ and homeowner post-flood reconstruction decisions. It is validated against damage assessments and post-storm surveys. The contribution of socio-economic factors and built environment on model performance is also addressed and suggests that mitigation for townhouse communities will be challenging.

Bio: Kim McEligot is a PhD candidate in the Department of Systems Engineering and Operations Research at George Mason University. His research interests include federation of computational fluid dynamics coastal flood modeling with geo-spatial agent-based modeling for individual and community level flood mitigation policy analysis. He holds an M.S. in Systems Engineering from Johns Hopkins University, and an M.A. in National Security and Military Affairs from the U.S. Naval War College. His email address is kmceligo@masonlive.gmu.edu.

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Deloitte Consulting’s Intoy and Baeder present

Welcome to the first seminar of the fall semester.

The Research Colloquium on Computational Social Science/Data Sciences speakers for Friday, September 06, 2019, will be Ben Intoy, PhD and Dan Baeder from Deloitte Consulting LLP. Their talk, entitled “Massive-Scale Models of Urban Infrastructure and Populations,” will begin at 3:00pm in the Center for Social Complexity Suite (373-381) located on the 3rd floor of Research Hall. The talk will be followed by a Q&A session along with light refreshments.

For announcements regarding this and future streams, please join the CSS/CDS student and alumni Facebook group: https://www.facebook.com/groups/257383120973297/

For a list of upcoming and previous seminars, please visit: https://cos.gmu.edu/cds/calendar/

We hope to see you on Friday, September 06, 2019 at 3PM.

Abstract:

As the world becomes more dense, connected, and complex, it is increasingly difficult to answer “what-if” questions about our cities and populations. Most modeling and simulation tools struggle with scale and connectivity. We present a new method for creating digital twin simulations of city infrastructure and populations from open source and commercial data. We transform cellular location data into activity patterns for synthetic agents and use geospatial data to create the infrastructure and world in which these agents interact. We then leverage technologies and techniques intended for massive online gaming to create 1:1 scale simulations to answer these “what-if” questions about the future.

Bios:

Ben Intoy is a full stack developer at Deloitte Consulting LLP. He received his PhD in Physics at Virginia Tech in 2015 where he used high throughput computing simulations to study stability properties of cyclically competing species in varying spatial dimensions. After completing his PhD, Ben went to the University of Minnesota, Twin Cities campus, as a postdoctoral research associate where he used tools he learned in his PhD to abstractly study the origin of life on earth and the probability of finding life elsewhere in the universe. In fall 2018, he took a position at the Deloitte Arlington, VA office to work on the FutureScape project (www.futurescape.ai).

Dan Baeder is a data scientist at Deloitte Consulting LLP, and has been on the FutureScape project since joining the firm last year. While at Deloitte, Dan focuses on the use of cellular phone geolocation data for the development of synthetic traffic models, as well as the application of geospatial analysis techniques to human behavior modeling. He is a noted R-phile in a sea of Python users. Dan received an MS in Public Policy and Management with a focus on data analytics from Carnegie Mellon University in 2018.

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Seminar programs to return in September