Events
Past Event
WED@NICO SEMINAR: Cedric Langbort & So Sasaki, University of Illinois "Some Models of Content Moderation for Social Networks in the Presence of Competition"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details

Speakers:
Cedric Langbort & So Sasaki, Coordinated Science Lab, University of Illinois at Urbana–Champaign (UIUC)
Title:
Some Models of Content Moderation for Social Networks in the Presence of Competition
Abstract:
The past decade has witnessed a range of shifting and sometimes contradictory behaviors among social media platforms regarding their content moderation policies. These behaviors often seem to have been adopted more as reactions to societal and legal pressures than as strategic choices aimed at better serving the platform's users or beating the competition. It is natural to wonder, however, whether a platform’s set of regulations, or lack thereof, can be used as a competitive advantage, since users may choose to switch to a competitor if they feel that the moderation rules in place limit their access to content they value.
We aim to address this question in this talk by asking what content moderation policy a platform should chose to satisfy its base and/or to become/remain dominant in a market where platforms compete for users and their attention.
More precisely, we consider two stylized settings (both being extensions of Morris' celebrated model of network contagion, one where platforms can curb the amount of deception employed by a news source, the other where they directly choose the kind of content that is allowed to circulate) and determine policies that two strategic and competing platforms can sustain in equilibrium when their users value both content and social interaction. In the first setting, we further investigate how the effectiveness of the policy depends on parameters such as network structure, news virality or size and cohesiveness of in-network communities... In the second setting, we study whether tailoring the moderation policy to different subgroups may help a platform better serve its users when it is in competition with others. While these models admittedly make a number of simplifying assumptions, which we discuss, we believe they provide valuable insight towards an economically normative view of content moderation for social networks.
Speaker Bio:
Cedric Langbort is a Professor of Aerospace Engineering at the University of Illinois at Urbana Champaign (UIUC), where he is also affiliated with the Decision & Control Group at the Coordinated Science Lab (CSL), and the department of Electrical and Computer Engineering. He works on applications of control, game, and optimization theory to a variety of fields and co- founded and co-directed the Center for People & Infrastructures at CSL. His and his advisees’ work have garnered multiple recognitions such as a NSF CAREER Award, a Siebel Energy Institute Research Award, an IEEE CDC Best Student Paper Award and a NDSEG fellowship. Most recently, he has been leading a US DoD MURI project on Information Exchange Network Dynamics funded by ARO, in which, along with psychologists, communication scientists and behavioral economists, he investigates the dynamics of (mis)information over networks.
So Sasaki received his Bachelor and Masters of Engineering in Aeronautics and Astronautics from the University of Tokyo, as well as an M.S. in Electrical Engineering from UC San Diego. He is currently working toward his Ph.D. degree at the Decision and Control Group, Coordinated Science Lab, University of Illinois at Urbana–Champaign. His research interests include game, optimization, control, graph theory, and machine learning, with application to social media.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/95560170313
Passcode: NICO25
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. 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.
Time
Wednesday, January 29, 2025 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Aparna Baskaran, Brandeis University "Measuring Active Stress: Vignettes of Data Driven Approaches Applied to the MT-Kinesin Active Fluid"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details

Speaker:
Aparna Baskaran, Professor of Physics, Brandeis University
Title:
Measuring Active Stress: Vignettes of Data Driven Approaches Applied to the MT-Kinesin Active Fluid
Abstract:
In this talk, we will begin with big picture discussion of that "Active matter" looks like from a materials physicist's perspective at the present time. Then, we will review the specifics of an experimental active matter system of in vitro suspension of purified cytoskeletal proteins. The meat of the talk will discuss some recent work to employ data driven techniques to extract material parameters and understand the complex emergent phenomenology of this fluid system.
Speaker Bio:
Aparna Baskaran received her undergraduate degree from Pondicherry University in 2001 and her Ph.D. from the University of Florida in 2006. She is a professor in the Martin A. Fisher School of Physics at Brandeis University, where she has been on the faculty since 2010. Her research centers on understanding theoretical principles that underlie nonequilibrium phenomena in soft materials and physical biology. Aparna's research involves close collaboration with experimentalists and computer simulators to understand and model particular systems, from which she extracts theoretical ideas that transcend the context of their origin and apply to broad classes of nonequilibrium systems. She is a beloved teacher and passionate exponent of her science.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/92035300595
Passcode: NICO25
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. 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.
Time
Wednesday, February 19, 2025 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Morgan Frank, University of Pittsburgh "AI, Complexity, and the Future of Work"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details

Speaker:
Morgan Frank, Assistant Professor, Department of Informatics and Networked Systems, University of Pittsburgh
Title:
AI, Complexity, and the Future of Work
Abstract:
Artificial Intelligence has evolved and now challenges our understanding of skills, careers, and the future of work. Using a variety of data on employment, occupations’ skill requirements, millions of resumes, and unemployment data from US states’ unemployment insurance offices, this talk will explore how workers’ skills shape their careers and how automation estimates fit into a framework for career adaptability and the economic resilience of labor markets. Work from this talk comes from a variety of publications in PNAS, Nature Communications, and Science Advances.
Speaker Bio:
Morgan Frank is an Assistant Professor at the School of Computing and Information at the University of Pittsburgh. Morgan is interested in the complexity of AI, the future of work, and the socio-economic consequences of technological change. While many studies focus on phenotypic labor trends, Morgan’s recent research examines how genotypic skill-level processes around AI impact individuals and society. Combining labor research with investigations into the nature of AI research and the social or societal implications of AI adoption, Morgan hopes to inform our understanding of AI’s impact. Morgan has a PhD from MIT’s Media Lab, was a postdoc at MIT IDSS and the IDE, and has a master’s degree in applied mathematics from the University of Vermont where he was a member of the Computational Story Lab.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/91407653122
Passcode: NICO25
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. 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.
Time
Wednesday, February 26, 2025 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Neda Bagheri, University of Washington "Computational modeling of emergent spatiotemporal cell population dynamics"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details

Speaker:
Neda Bagheri, Associate Professor, Department of Biology, University of Washington
Title:
Computational modeling of emergent spatiotemporal cell population dynamics
Abstract:
Computational models are essential tools that can be used to simultaneously explain and guide biological intuition. My lab employs agent-based modeling, machine learning, and dynamical systems to explain biological observations and interrogate multi-lateral regulatory networks that drive individual cellular decisions as well as cell population dynamics. We are interested in the inherent multiscale nature of biology, with a specific focus on system-level dynamics that emerge from interactions of simpler individual-level modules.
In this presentation, I introduce a multiscale agent-based model of a generic solid tumor microenvironment that integrates subcellular signaling and metabolism, cell-level decision processes, and dynamic vascular architecture and function. We use this modeling framework to understand decision processes among heterogeneous cell agents in changing microenvironments. The model is open-source and flexible/adaptable (it can characterize countless cell population dynamics!), but it is computationally costly to simulate and analyze at large scales. I highlight these challenges along with strategies to mitigate them, and showcase successes that derive from our model development process. I also describe how the model can be used to inform the design of experiments, interventions, and hypotheses that modulate population level responses.
Speaker Bio:
Neda Bagheri earned her doctorate in Electrical Engineering from the University of California in Santa Barbara. Her focus on control theory and dynamics piqued her interest in biology. After completing a postdoc in Biological Engineering at MIT, she joined the Chemical & Biological Engineering faculty at Northwestern University (2012). In 2019, she was recruited to both the University of Washington Seattle (where she holds a joint position in Biology and Chemical Engineering) and the Allen Institute for Cell Science.
In recognition for her research accomplishments and vision, Bagheri was awarded a National Science Foundation CAREER Award (2017) and a Senior Moulton Medal (2020). She was honored as a Distinguished Speaker for the Accelerated Discover Forum at IBM Research-Almaden (2018) as well as for the Mindlin Foundation (2019), and as the Plenary Speaker for the triennial International Federation of Automatic Control DYCOPS conference (2022). She serves on multiple science advisory and editorial boards, guiding the frontier of multidisciplinary research.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/97273424116
Passcode: NICO25
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. 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.
Time
Wednesday, March 5, 2025 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Michael Dickey, NC State University "Shaping a Soft Future"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details

Speaker:
Michael Dickey, Camille & Henry Professor, Department of Chemical and Biomolecular Engineering, NC State University
Title:
Shaping a Soft Future
Abstract:
Existing devices—such as cell phones, computers, and robots – are made from rigid materials, which is in direct contrast to the soft materials that compose the human body. In this talk, I will discuss several topics related to studying and harnessing soft materials within the context of creating devices (actuators, sensors, electronics) with tissue like properties.
· Liquid metal: Gallium-based liquid metals are often overlooked despite their remarkable properties: melting points below room temperature, water-like viscosity, low-toxicity, and effectively zero vapor pressure (they do not evaporate). Normally small volumes of liquids with large tension form spherical or hemi-spherical structures to minimize surface energy. Yet, these liquid metals can be patterned into non-spherical shapes (cones, wires, antennas) due to a thin, oxide skin that forms rapidly on its surface. Recently, we have discovered a simple way to separate the oxide from the metal as a way to deposit 2D-like oxides at ambient conditions.
· Shape reconfiguration: Perhaps the most fascinating aspect of liquid metals it the ability to use interfacial electrochemistry chemistry to remove / deposit the oxide to manipulate the surface tension of the metal over unprecedented ranges (from the largest tension of any known liquid to near zero!). This allows manipulating the shape and position of the metal for shape reconfigurable devices.
· Ionogels: Soft materials that are tough (that is, they do not readily tear or fail mechanically) are important for a number of applications, including encapsulation of devices. Recently, we discovered a simple way to create ulta-tough ionogels, which are polymer networks swollen with ionic liquids. These materials are tougher than cartilage and compatible with 3D printing.
This work has implications for soft and stretchable electronics; that is, devices with desirable mechanical properties for human-machine interfacing, soft robotics, and wearable electronics.
Speaker Bio:
Michael Dickey received a BS in Chemical Engineering from Georgia Institute of Technology (1999) and a PhD from the University of Texas (2006) under the guidance of Professor Grant Willson. From 2006-2008 he was a post-doctoral fellow in the lab of Professor George Whitesides at Harvard University. He is currently the Camille and Henry Dreyfus Professor in the Department of Chemical & Biomolecular Engineering at NC State University. He completed a sabbatical at Microsoft in 2016 and EPFL in 2023. Michael’s research interests include soft matter (liquid metals, gels, polymers) for soft and stretchable devices (electronics, energy harvesters, textiles, and soft robotics).
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/96920996561
Passcode: NICO25
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. 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.
Time
Wednesday, March 12, 2025 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
Winter Classes End
University Academic Calendar
All Day
Details
Winter Classes End
Time
Saturday, March 15, 2025
Contact
Calendar
University Academic Calendar
Spring Classes Begin - Northwestern Monday: Classes scheduled to meet on Mondays meet on this day.
University Academic Calendar
All Day
Details
Spring Classes Begin - Northwestern Monday: Classes scheduled to meet on Mondays meet on this day.
Time
Tuesday, April 1, 2025
Contact
Calendar
University Academic Calendar