APRIL MEETING: Thursday, April 30, 2026 at 5:00pm (US Central)

LOCATION:
ESAM Conference Room, Tech M416
2145 Sheridan Road, Evanston, IL 60208

AGENDA:
PLEASE NOTE: this event is starting at 5pm this month.
5:00pm - Meet and greet with refreshments
5:30pm - Talk with Joshua Stadlan, Research Associate Professor, Northwestern Institute on Complex Systems (NICO); Core Faculty, Center for Computational & Social Sciences in Health (COMPASS)

TALK TITLE:
Why do we Socialize in Bursts? Using data and Particle Models to Study Human Interaction

ABSTRACT:
At large social events, conversations do not happen at a steady pace. Many are short and clustered together, while some last much longer or are separated by long gaps. This “burstiness” affects how people connect and how disease, news, or opinions spread through groups. In this talk, I use data and simple particle models to explore possible explanations for social burstiness. A common idea is that some people naturally attract more attention, which can generate burstiness. I show that simpler models can also generate burstiness, even without building in fixed differences between people. Join us in exploring how observational data and theory-driven modeling can together test explanations for patterns in our social lives.

DATA SCIENCE NIGHTS are monthly meetings featuring presentations and discussions about data-driven science and complex systems, organized by Northwestern University graduate students and scholars. Students and researchers of all levels are welcome! For more information: http://bit.ly/nico-dsn

FUTURE DATES:
Data Science Nights will be held on Thursday evenings in the winter and spring terms, with future dates May 28, 2026.

Related Info

Speaker:

Daniel B. Stouffer, Research Group Leader, Department of Evolutionary and Integrative Ecology, the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany

Title:

Conceptual and Theoretical Challenges in the Study of Multi-Species Coexistence

Abstract:

The population dynamics of most ecological communities unfold on temporal scales that cannot be fully studied in the laboratory or field. The generation times of trees, for example, are so long and varied that we may need to wait decades to determine how a whole, interconnected forest community responds to a changing climate. Many researchers thus use models to generate predictions that go beyond the bounds of what is experimentally tractable. To do so, it has become common to follow the "model-paramerisation paradigm". For example, a researcher interested in forest dynamics would not conduct long-term experiments to directly probe whether one tree species is ever competitively excluded by any other(s). Instead, they would use data from shorter-term experiments to estimate the parameters of a presupposed model, and then study whether or not their empirically parameterised model predicts competitive exclusion or coexistence. As powerful as this perspective has proven to be, it routinely hinges on multiple key assumptions that limit its versatility. I will describe recent and ongoing work that challenges these assumptions, while also describing some unexpected hurdles encountered along the way.

Speaker Bio:

Daniel B. Stouffer is a Research Group Leader in the Department of Evolutionary and Integrative Ecology at the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany. His group adopts a variety of computational, statistical, and analytical approaches to overcome ecological communities' innate complexity while exploring fundamental biological questions. They work on a variety of topics and systems and are particularly interested in understanding the emergent ecological and evolutionary consequences that arise due to interactions between species.

Location:

In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/98364690035

About the Speaker Series:

Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, networks, and artificial intelligence. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.

Related Info

Speaker:

Hamsa Bastani, Associate Professor of Operations, Information, and Decisions, and Statistics and Data Science, Wharton School, University of Pennsylvania

Title:

Challenges in Achieving Human-AI Collaboration

Abstract:

TBA

Speaker Bio:

Hamsa Sridhar Bastani is an Associate Professor of Operations, Information, and Decisions (OID) and Statistics and Data Science at the Wharton School of the University of Pennsylvania, where she co-direct the Wharton Healthcare Analytics Lab. Her research sits at the intersection of machine learning, operations research, and economics. She studies how to design, deploy, and evaluate AI systems that empower human decision-makers and improve societal outcomes.

Professor Bastani aims to combine methodological depth with implementation in consequential environments. She has worked with national governments to deploy algorithms at the country scale for targeted border COVID-19 screening and essential medicine access, and has co-led one of the first large field studies of generative AI tutors in high school mathematics. She studies both the mathematical properties of algorithms and the way people respond to them.

Her research has been published in leading outlets including Nature, Management Science, Operations Research, and PNAS, and has garnered numerous recognitions, including the Wagner Prize for Excellence in Operations Research, the INFORMS Pierskalla Award for best healthcare paper, and the George Nicholson Prize. Previously, she graduated summa cum laude from Harvard in 2012 with an A.M. in physics and an A.B. in physics and mathematics, completed her PhD in Stanford's Electrical Engineering department under the supervision of Mohsen Bayati, and spent a year as a Herman Goldstine postdoctoral fellow at IBM Research.

Location:

In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/99847338986

About the Speaker Series:

Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, networks, and artificial intelligence. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.

Related Info

NICO is looking for participants to share 12-15 minute lightning talks on their current research. To sign up, please fill out this short survey. These are open to Northwestern graduate students, postdoctoral fellows, and visiting scholars!

All talks will be given in person at Chambers Hall and this event will also be livestreamed via Zoom.

Speakers will be balanced based on their topics/disciplines in order to provide a broad representation of the research activities at NICO

Location:

In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/98031689779

About the Speaker Series:

Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, networks, and artificial intelligence. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.

Related Info