Category: News and Events

On 14 February 2023, we were notified that by the Senior Associate Dean Ali Andalibi that the Center was approved for three years starting 1 Jan 2023 and that will expire 31 Dec 2026. The approval does not obligate the College of Science to financially support the Center. We must be financially self-sufficient.

While nuclear weapons of mass destruction exist, thankfully they have only been used in anger twice. Therefore, there is little know about how people will react to them. As a consequence of this unknown, we synthesized a hundred years of disaster research to build a model to explore this gap in our understanding of the social effects of a nuclear weapon of mass destruction (NWMD). By reviewing disaster literature, we argue that disasters, including a NWMD, should be viewed as a complex system of three parts (i.e., the physical, social and individual). These three parts inform an agent-based model on how society might react following a nuclear weapon of mass destruction. Specifically, the agent-based model captures the main properties of complex adaptive systems such as heterogeneity, webs of connections (i.e., social networks), relationships and interactions, and adaptations arising from individual actions and decisions. Our NWMD model represents the road network and weapon effects as part of the physical environment. It also includes synthesized individuals and their social environment through agents’ social networks and emergent group dynamics after the event. This NWMD model supports the exploration of the effects of different agent behavior in times of disaster. In the base model, we characterized the response of victims of a nuclear WMD, first responders, and the rest of the population not directly impacted by the weapon. Such a model of the New York mega-city is poised to support additional studies of social effects of a nuclear WMD or disasters more generally.

Read more…

Dr. Annetta Burger, a recent graduate of the CSS program now a post-doc at NYU presented a paper based on her dissertation on complex adaptive systems as an organizing approach to understanding disasters and impacts on public health to the European Public Health Webinar on Friday, 22 October 2021 (remotely) with some assistance from with Bill Kennedy. The presentation was well received and will hopefully influence thinking about public health and disasters.

The Society for Modeling and Simulation International (SCS) awarded Hamdi Kavak, Assistant Professor, Computational and Data Sciences (CDS), the 2021 Young Simulation Scientist Award. The award recognizes scientists and engineers under the age of 35 who demonstrate excellence and leadership qualities in the field of modeling and simulation. He is the first from Mason to receive this award.

“SCS is one of the most prestigious modeling and simulation societies in the world and, at most, one Young Simulation Scientist award is given each year,” said Kavak. “I am thankful and proud to be one of the four people who have received this award since its inception.”

Kavak’s research focuses on the intersection of simulation modeling and data science and ways these connections may solve some of the greatest challenges seen in modeling. His work includes simulations and analysis of diseases, cyber warfare, population behavior, and malicious attacks against supply chain networks.

His recent summer research included a provost-funded Summer Team Impact Project and mentoring ASSIP high school and Mason college students to, according to Kavak, “understand and predict the COVID-19 pandemic from vaccine hesitancy to the emergence of new strains.”

In addition to teaching at the graduate and undergraduate level, Kavak serves as the Co-director of the Center for Social Complexity. His research support spans several organizations including the National Science Foundation, the Commonwealth Cyber Initiative, the Defense Threat Reduction Agency, and the Department of Homeland Security.

While many mathematical and statistical models in the social sciences consist of interacting agents, it is often the case that strong assumptions have to be made for reasons of analytical tractability (e.g., representative agents, rational agents, equal probability of interaction between agents, attainment of agent-level equilibrium).

Agent-based models (ABMs) are an emerging computational approach for studying social and natural phenomena in terms of interacting agents, and which facilitate the relaxation of unrealistic assumptions. Often ABMs address social phenomena about which other more conventional models exist, but direct comparisons of the output of the distinct models are not made directly or else are attempted only informally.

This workshop will focus on ABMs that reproduce the results of conventional models, and then generalize standard results by relaxing model specifications, usually in the direction of more realism. Such models agentize mathematical or econometric models and may demonstrate that conventional results are robust to certain parametric variations or are special cases of more general results.

The workshop on agentization will be held online through George Mason University, from 15-17 September, organized by the Computational Public Policy Lab and the Center for Social Complexity at Mason and sponsored by the Proteus Foundation. ABM pioneer W. Brian Arthur (Santa Fe Institute) will deliver a keynote address. We seek submissions of ABMs that closely reproduce conventional model results and then generalize them. Perhaps you have created an ABM that is similar to some standard model but which produces different results. If your ABM can be directly related to the standard model then it is of interest to this workshop. ABMs that have only notional relation to extant models are not suitable for this event.

People interested in presenting their research at this workshop should submit online by 16 August, either as a paper comparing results from an ABM to standard results, or as an abstract along with a working ABM or model output demonstrating the salience of an ABM to some existing model. It is our hope to combine a variety of papers describing agentized models from the workshop into an edited book or journal special issue. ABMs are welcome from any domain in which social processes are important. People interested in sitting in on or otherwise participating in this workshop are welcome to indicate their interest through the website. This is a free event.

We are happy to announce Dr. Hamdi Kavak as the new co-director of the Center for Social Complexity starting May 12, 2021. Since 2019, Dr. Kavak has been a faculty member of the Center and Assistant Professor at the Computational and Data Sciences Department at GMU. His research focuses on the intersection of modeling and simulation and data science. With this change, Dr. Kavak replaced the former co-director Dr. Andrew Crooks, who joined the University at Buffalo in Fall 2020. We congratulate Dr. Kavak on this new role and thank Dr. Crooks for his exceptional service.

Due to the Thanksgiving break, there will be no Research Colloquium on Computational Social Science/Data Sciences on Friday, November 29.

The seminar will resume on Friday, December 6, with Eileen Young, Graduate Research Assistant, Disaster Research Center, University of Delaware, who will be presenting “An Agent-Based Model of the Social Dimensions of Fire Evacuation.”

The speaker for Friday, November 22, 2019, will be Mahdi Hashemi, Assistant Professor, Department of Information Sciences and Technology, George Mason University. Dr. Hashemi’s talk entitled “Machine Learning for Smart Cities,” 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/

Please join us!

Abstract: Cities are growing physically and digitally, faster than ever. The ever-growing population of cities, along with their intrinsic inaccessibility and inequity, has created difficulties with traffic, mobility, safety, health, pollution, and misinformation among many others. The physical and digital growth of cities outpaces the effort to address the aforementioned issues.

The growing popularity of online social networks (OSN) and World Wide Web (WWW) has remarkably expedited the information dissemination among individuals and groups. Digital data is the lifeblood of modern cities. Today, it’s being captured in large quantities at unprecedented rates via ubiquitous devices and sensors. Unfortunately, most of the generated data is wasted without extracting potentially useful information and knowledge because of the lack of established mechanisms that benefit from the availability of such data. That has turned the discussion from how the massive amounts of data are collected to how knowledge can be extracted from them.

Smart cities become smart not only because they automate routine functions serving the citizens, buildings, and traffic systems but also because they enable monitoring, understanding, analyzing and planning the city to improve the efficiency, equity, and quality of life for its citizens in real time. With physical and digital problems on one hand and big data on the other, smart cities strive to juxtapose them to find inexpensive solutions. How the digital data should be processed to help solve problems in cities remains one of the major areas of research and development in recent years and the focus of this talk

Bio: Mahdi Hashemi is an Assistant Professor in the Department of Information Sciences and Technology at George Mason University. He leads the Machine Learning and Smart Cities Group, where he also specializes in intelligent transportation, spatial-temporal data and web/social media analytics. Dr. Hashemi earned his Ph.D. in Computing and Information from the University of Pittsburgh

will speak at the Research Colloquium on Computational Social Science/Data Sciences this Friday, November 15, 2019. Brown, P.E., Ph.D., Storm and Stream Solutions, LLC, Principal/Founder, will speak on “To Be or Not To Be: Introducing the Green Stormwater Infrastructure Social Spatial Adoption (G-SSA) Model” 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: The use of incentives in stormwater programs is a common feature that is used to motivate private property owners as well as land developers to adopt specific types of stormwater management infrastructure at the site or parcel level. While incentives for land developers, such as reduced plan review time or reduced plan review fee for projects that utilize specific BMPs, such as green stormwater infrastructure (GSI), are helpful policies in driving implementation of innovative stormwater practices, this implementation is limited to land development activity. Approximately 75% of existing impervious cover is associated with land development activities that took place prior to federal legislation focused on urban stormwater runoff. The implication of this is that a majority of impervious cover across the U.S. discharges runoff that is either inadequately managed or not managed at all. Until we address these existing areas, impacts from these areas will continue to impact our waters. This is reflected by evolving regulations that require a certain amount of existing impervious cover to be retrofitted to provide stormwater management. Many cities, such as Milwaukee, Seattle and Atlanta, also have retention volume goals as part of a regulatory program as well as an effort to increase the resilience and sustainability of urban areas.

The motivation to retrofit existing impervious areas is a driver to retrofit both public and private lands. Public rights-of-way (ROWs) are often challenging to work within, and there is a limited amount of public ROW available. Overall, 60% of land in the U.S. is privately held, with large portions of these areas located in large public parks in Mountain Region states. The result is that many states have private land ownership rates at 80% or higher; clearly this is a need to find ways to locate urban stormwater retrofits on private lands.

The default method of incentivizing private land owners to adopt onsite stormwater infrastructure is a stormwater fee reduction according to the 2018 Black and Veatch Stormwater Utility Survey. The limitation with this approach comes in when a community does not have a stormwater utility established, which is the case for at least 2/3 of the regulated stormwater entities in the country. And even if a utility exists, the fees are often not high enough to make economic sense for onsite adoption when considering payback periods and other financial metrics. The reason for this is simple – stormwater utility fees are set at a level/rate to pay for needed stormwater programmatic and implementation rather than to create an effective financial incentive for private parcel owners to adopt BMPs onsite. The result of this are participation rates in incentive-based stormwater infrastructure on-site investments of 2-5% or lower associated with traditional incentive programs, which also include cost-sharing and subsidy programs as well. Due to this reason, communities are considering market-based approaches, such as stormwater credit trading, that can reward private property owners in a more robust way for onsite BMP adoption.

While market-based programs hold much promise, the focus of research in this area has been (rightly) on program architecture and policies with the view of “if we build it, they will come”. However, this leaves a void in understanding on how parcel owners will respond to market-based option. Questions regarding the motivations for adoption, how decisions on adoption are made, and how adoption on parcels affect adoptions in neighboring areas or parcels. This presentation will outline research done to begin to address the “consumer behavior” view of BMP adoption. Specifically, a socio-economic model based upon cellular automata-style agent-based modeling will be presented to illustrate a method to capture the adoption of GSI across multiple urban neighborhoods that comprise a city-wide landscape.

This model – the Green Stormwater Infrastructure Social Spatial Adoption (G-SSA) model – provides insights on neighboring effects, spatial dynamics, and decision-making aspects of GSI adoption based upon social theory. Model sensitivity analysis highlights the significance of social and spatial model elements to overall GSI adoption rates and pattern. An applied G-SSA model has been developed and explored to simulate the complex emergent patterns for GSI adoption across a specific cityscape (Washington, D.C.). Applied G-SSA model output is consistent with expected model behavior as well as observed and document GSI adoption patterns in Washington, D.C.

Bio: Seth Brown is the Principal and Founder of Storm and Stream Solutions, LLC, a consulting firm providing a range of services in the stormwater sector. He is the Executive Director of the National Municipal Stormwater Alliance (NMSA), which is a 501.c.3 representing state and regional organizations focused on stormwater issues. Seth is also the Senior Stormwater Advisor with the Water Environment Federation (WEF) where he supports national-level technical and policy initiatives associated with stormwater issues. He has a PhD from George Mason University in the Department of Civil, Environmental and Infrastructure Engineering and is a licensed professional engineer in the state of Maryland.

The Research Colloquium on Computational Social Science/Data Sciences speaker for Friday, November 08, 2019, will be John Schuler, Ph.D. candidate, Department of Economics, George Mason University. John’s talk entitled “The Econometrics of Prices in a Network Economy” 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: According to classical economic theory, removing money from the economy should result in prices falling. However, there is some evidence of so-called Cantillon effects where some prices initially move in the wrong direction. There exists an agent-based model that replicates this phenomenon using a network model. My focus is on the econometric plausibility of this model. I will demonstrate a preliminary statistical model to defend the assumptions made for the agent-based model.

Bio: John Schuler is a fifth year PhD student in the Department of Economics at George Mason University. John graduated from American University with an MS in statistics in 2017 and from St. John’s College with a BA in liberal arts in 2009. He also spent a year at the University of Maryland, College Park studying mathematics post-baccalaureate, and more recently he spent the Spring 2018 semester as a visiting assistant professor at Washington College. His research interests involve the interface of computer science and economics as well as agent based macroeconomics.