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The Origin of Agriculture in the Peiligang Culture

The CSS seminar speaker for Friday, February 27, 2017, will be Yang Zhou, PhD Student, Computational Social Science, Department of Computational and Data Sciences, George Mason University. Yang’s talk, entitled “The Origin of Agriculture in the Peiligang Culture: An Agent-based Modeling Approach” (abstract below), is scheduled to 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 newly created CSS program YouTube channel: https://www.youtube.com/channel/UC7YCR-pBTZ_9865orDNVHNA

Abstract: The emergence of agriculture played an important role in human history as it allowed people to move from a nomadic (i.e. hunter-gather) to a sedentary (i.e. agricultural) lifestyle. This shift in lifestyle not only provided abundant food, but also sufficient numbers of non-cultivating specialists, which are necessary conditions for the rise of a civilization. However, questions about how and why agriculture originated have remained controversial. This paper explores the origin hypotheses of agriculture, using the canonical theory of social complexity as a framework to study the transition from hunter-gatherer to agricultural societies in the region of the Peiligang in China based on existing literature, and develops an agent-based model to simulate the transition process. The model assumes that a combination of population growth and gaining knowledge on plants drove the transition from hunter-gatherer to agriculture. Results show that based on the basic hypotheses and assumptions, the model is able to generate the key phases that are identical with the existing literature on such a transaction.


Dr. Nigel Gilbert of the University of Surrey, a leading scientist in the field of Computational Social Science, as well as long-time friend of our Center and a member of our original External Board, has been appointed Commander of the British Empire (CBE) by H.M. Queen Elizabeth II. Congratulations, Nigel!


Doctorates in Computational Social Science were conferred upon ten of our CSS students at the recent Convocation ceremony for the College of Science. We are so proud of them and of their tremendous accomplishment. Following are the students along with the titles of their dissertations:

  • Thomas J. Dover, Implementing a Complex Social Simulation of the Violent Offending Process: The Promise of a Synthetic Offender
  • Jose Manuel Magallanes, Climate Change and the Potential for Conflict and Extreme Migration in the Andes: A Computational Approach for Interdisciplinary Modeling and Anticipatory Policy Making
  • David P. Masad, Agents in Conflict: Comparative Agent-based Modeling of Intrnational Crises and Conflicts
  • Hugh James McFarlane, An Agent-based Model of Community Authority Structure Resilience
  • Cristina Metgher, A Computational Social Science Approach to the Social Determinants of Cancer
  • Nathan Palmer, Individual and Social Learning: Bounded Rationality from First Principles
  • Ovi Chris Rouly, Towards Emergent Social Complexity
  • Holly Ann Russo, Explaining Box Office Performance from the Bottom up: Data, Theories, and Models
  • Stephen L. Scott, Computational Modeling for Marine Resource Management
  • Hyungsik Shin, An Essay on Micro Heterogeneity and the Evolution of Inequality

Posted 5/12/16.



Multi-Level Regulation in Mammalian Circadian Clock

Casey Diekman (Department of Mathematical Sciences, New Jersey Institute of Technology)

DATE: Monday, 11 April, 2016
TIME: 4:00-5:00pm
LOCATION: Lecture Room (Room 229)
Krasnow Institute Building
George Mason University, Fairfax, VA

Abstract:

Circadian (~24-hour) rhythms offer one of the clearest examples of the interplay between different levels of nervous system organization, with dynamic changes in gene expression leading to daily rhythms in neural activity, physiology, and behavior. The main output signal of the master circadian clock in mammals has long been believed to be a simple day/night difference in the firing rate of neurons within the suprachiasmatic nucleus (SCN). Our recent findings challenge this theory, and demonstrate that a substantial portion of SCN neurons exhibit a more complex and counterintuitive set of electrical state transitions throughout the day/night cycle. In this seminar, I will attempt to provide a mathematical understanding of these daily transitions in SCN electrical state and the functional roles they play in the mammalian circadian clock.



How Firing Rate Heterogeneity is Mediated by Intrinsic and Network Heterogeneity

Monday, March 14, 3pm
Krasnow Institute Room 229
Fairfax Campus

Cheng Ly
Assistant Professor, Statistics & Operations Research Department
Virginia Commonwealth University

Abstract:
Heterogeneity of neural attributes has recently gained a lot of attention and is increasing recognized as a crucial feature in neural processing. Recent experimental recordings in electric fish indicate that the heterogeneous network input can mediate response heterogeneity of superficial pyramidal cells in a cortical area (Marsat Lab, WVU). These data motivated us to theoretically study how heterogeneity of neural attributes in general alter firing rate heterogeneity. We ask how 2 sources of heterogeneity: network (synaptic heterogeneity) and intrinsic heterogeneity alter response heterogeneity.

First we address this in a canonical recurrent spiking network model with random connectivity (Erdos-Renyi graph). The relationship between intrinsic and network heterogeneity can lead to amplification or attenuation of firing rate heterogeneity, and these effects depend on whether the recurrent network is firing asynchronously or rhythmically. We analyze the system and derive compact analytic formulas to precisely describe the phenomena.

Second, we adapt our theory to a delayed feedforward neural network to better model the electric fish system. The theory is used to demonstrate that a feedforward network with structured connectivity rules exhibit qualitatively similar statistics as the experimental data. Specifically, the stimulus tuning of particular cells is related to the network architecture, i.e., the number of synaptic connections. Thus, the model demonstrates that intrinsic and network attributes do not interact in a linear manner but rather in a complex stimulus-dependent fashion to increase or decrease response heterogeneity and thus shape population codes.

This is joint work with Gary Marsat (West Virginia University).
Claudio Cioffi, Joey Harrison, and Meysam Alizadeh, members of the CSC component of the Minerva Project on Radicalization, along with the University of Maryland, the University of Michigan, and the University of Warsaw, presented their work at the 2015 Minerva Meeting and Program in September. At the meeting sponsored by ONR, MASON models drew attention and praise for being at the cutting edge of agent-based simulation research.

Posted 11/12/15


Dr. Shu-Hen Cheng, professor, from National Cheng-chi Univerisity (NCCU) in Taipei, Taiwan, and editor of several noted academic journals, visited the Center for Social Complexity recently to discuss the future of collaboration between our respective groups. Possible topics include agent-based and complexity modeling on domains such as computational historical dynamics, disaster modeling and risk analysis, and applications in economics and finance. Dr. Cioffi will visit Dr. Cheng at the new NCCU institute for computational social science in 2016.

Posted 10/26/15

Claudio Cioffi, Joey Harrison, and Meysam Alizadeh, members of the CSC component of the Minerva Project on Radicalization, along with the University of Maryland, the University of Michigan, and the University of Warsaw, presented their work at the 2015 Minerva Meeting and Program in September. At the meeting sponsored by ONR, MASON models drew attention and praise for being at the cutting edge of agent-based simulation research.

Posted 11/12/15


Dr. Shu-Hen Cheng, professor from National Cheng-chi Univerisity (NCCU) in Taipei, Taiwan, and editor of several noted academic journals, visited the Center for Social Complexity recently to discuss the future of collaboration between our respective groups. Possible topics include agent-based and complexity modeling on domains such as computational historical dynamics, disaster modeling and risk analysis, and applications in economics and finance. Dr. Cioffi will visit Dr. Cheng at the new NCCU institute for computational social science in 2016.

Posted 10/26/15


Dr. Claudio Cioffi attended attended the Global Humanitarian Technology Conference in Seattle October 8-11. This is one of several meetings leading up to his participation in global humanitarian science and technology forums to disseminate the new agent-based model NorthLands of the Mason-Smithsonian Joint Project.


New MASON Northlands Unveiled. Dr. Claudio Cioffi announced the new MASON NorthLands, an agent-based model of climate change and emergent societal impacts, at the annual conference of the European Social Simulation Association (ESSA), in Groningen, Netherlands, September 14-18. This is the main “federated” model of the Mason=Smithsonian Joint Project on Climate and Society, funded by the Cyber-enabled Discoveries and Innovation (CDI) Program of the the National Science Foundation (NSF).

Peter Froncek, GRA and member of the the joint team on the NorthLands model, will present his research on cultural evolution, building on R. Reynolds’s work with cultural algorithms, at the upcoming workshop on Computational Social Science in Cologne, Germany, this month. Peter also passed his qualifying doctoral exams with flying colors and is now preparing his doctoral dissertation proposal leading to candidacy. Sean Luke has released a new version of MASON (Multi-Agent Simulator of Networks and Neighborhoods), available from the MASON website.


Paper-of-Record published by Claudio Cioffi, Dan Rogers, and Bill Honeychurch, on the MASON Hierarchies model, created for advancing understanding of the rise and fall of polities in Inner Asia, including the Mongol Empire. Read: MASON HIERARCHIES: A LONG-RANGE AGENT MODEL OF
POWER, CONFLICT, AND ENVIRONMENT IN INNER ASIA
. 9/17/15


Qing Tian, CSS Faculty, has co-authored two papers published recently in professional journals:

Tian, Q., Brown, D.G., Bao, S, Qi, S. (2015). Assessing and mapping human well-being for sustainable development amid flood hazards: Poyang Lake Region of China. Applied Geography, 63, 66-76.

Tian, Q., Brown, D.G., Zheng, L., Qi, S., Liu, Y., Jiang, L. (2015). The role of cross-scale social and environmental contexts in household-level land-use decisions, Poyang Lake Region. Annals of Association of American Geographers. DOI: 10.1080/00045608.2015.1060921. 9/3/15


Cioffi and Crooks Lecture in Lipari. Claudio Cioffi and Andrew Crooks, Center for Social Complexity, were featured lecturers at the Lipari International Summer School in Computational Social Science held July 25-31 on Lipari Island, Italy. The theme of this year’s session was Algorithms, Data, and Models for Social and Urban System. For more information, visit the school’s web site 8/10/15


Bill Honeychurch, former CSC postdoc and adjunct CSS faculty member, now at Yale University, has a new book out. Inner Asia and the Spatial Politics of Empire, published by Springer, is available for purchase at Amazon. 7/22/15


Andrew Crooks and Bill Kennedy are serving as Acting Director and Senior Adviser, respectively, while Claudio Cioffi is acting as GMU’s Interim Vice President for research. Dr. Cioffi will return to his position as Director of the Center on August 25. 7/22/15


Former CSC researcher develops new MASON model. Ates Hailegiorgis, formerly with the Center for Social Complexity’s Mason-Smithsonian Joint Project on Climate Change and Societal Consequences, and affiliate faculty at the Center, is now with the US Geeological Survey, Leetown Science Center, where he has developed a new MASON model of the lower Mississippi Alluvial Region. For more information, go to http://www.lsc.usgs.gov/ 7/15/15