Events
Past Event
WED@NICO WEBINAR: Lillian Lee, Cornell University "Online Discussion Dynamics: Early prediction of controversy; content removal as a moderation strategy"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
Details
Speaker:
Lillian Lee, Charles Roy Davis Professor, Department of Computer Science and Department of Information Science, Cornell University
Title:
Online Discussion Dynamics: Early prediction of controversy; content removal as a moderation strategy
Abstract:
Part One: Controversial posts are those that split the preferences of a community, receiving both significant positive and significant negative feedback. Our inclusion of the word "community" here is deliberate: what is controversial to some audiences may not be so to others. Using data from several different communities on reddit.com, we predict the ultimate controversiality of posts, leveraging features drawn from both the textual content and the tree structure of the early comments that initiate the discussion. We find that even when only a handful of comments are available, e.g., the first 5 comments made within 15 minutes of the original post, discussion features often add predictive capacity to strong content-and-rate only baselines. Additional experiments on domain transfer suggest that conversation-structure features often generalize to other communities better than conversation-content features do.
Part Two: Moderators of online communities often employ comment deletion as a tool. We ask here whether, beyond the positive effects of shielding a community from undesirable content, does comment removal actually cause the behavior of the comment’s author to improve? We examine this question in a particularly well-moderated community, the ChangeMyView subreddit. The standard analytic approach of interrupted time-series analysis unfortunately cannot answer this question of causality because it fails to distinguish the effect of having made a non-compliant comment from the effect of being subjected to moderator removal of that comment. We therefore leverage a “delayed feedback” approach based on the observation that some users may remain active between the time when they posted the non-compliant comment and the time when that comment is deleted. Applying this approach to such users, we reveal the causal role of comment deletion in reducing immediate noncompliance rates, although we do not find evidence of it having a causal role in inducing other behavior improvements. Our work thus empirically demonstrates both the promise and some potential limits of content removal as a positive moderation strategy, and points to future directions for identifying causal effects from observational data
Joint work with Cristian Danescu-Niculescu-Mizil, Jack Hessel, Kumar Bhargav Srinivasan, Chenhao Tan
Speaker Bio:
Lillian Lee is the Charles Roy Davies professor in the departments of computer science and of information science at Cornell University. Her research interests include natural language processing and computational social science. She is a AAAI Fellow, an ACL Fellow, and an ACM Fellow, and a former Sloan Fellow. She received one of three inaugural awards for the Test of Time (2002-2012) Paper on Computational Linguistics (joint with Bo Pang), and best paper awards at NAACL 2004 (joint with Regina Barzilay) and the IJCAI 2016 Natural Language Processing meets Journalism workshop (joint with Liye Fu and Cristian Danescu-Niculescu-Mizil). She earned a citation in "Top Picks: Technology Research Advances of 2004" by Technology Research News (also joint with Regina Barzilay). Her co-authored work has received several mentions in the popular press, including The New York Times, NPR's All Things Considered, and NBC's The Today Show.
Webinar:
Zoom link: https://northwestern.zoom.us/j/99055485716
Passcode: nico
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems and data 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, May 19, 2021 at 12:00 PM - 1:00 PM
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Elizabeth Gerber, Northwestern University "Human–AI Systems That Amplify Human Connection at Work"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Elizabeth Gerber, Professor of Mechanical Engineering and Communication Studies, Northwestern University
Title:
Richer Together: Human–AI Systems That Amplify Human Connection at Work
Abstract:
AI in the workplace is often framed as a story of replacement. This talk flips that narrative. Drawing on research-informed, human-centered design, I present hybrid human–AI systems that scaffold—not supplant—our most distinctively human capacities: connection, reflection, and meaning-making. These systems are built on empirical insights into how people collaborate and learn, and it demonstrate how AI can be designed to increase metacognition and better prepare for more intentional, higher-quality human interactions. Rather than stripping work of its human core, AI—when designed in context and with care —can help make our work more relational, more effective, and more deeply human.
Speaker Bio:
Liz Gerber is a Professor in the Department of Mechanical Engineering and Communication at Northwestern University and creates sociotechnical platforms that make innovation accessible to everyone. Her research explores how new technologies can support the innovation process, particularly “collective innovation,” which taps into often unused human, social, and economic resources to discover, assess, and implement ideas. Through the Center for Human-Computer Interaction + Design, Delta Lab, and Design for America, her team develops collaborative networks that address complex issues—from healthcare access to climate resilience—promoting entrepreneurship and strengthening the link between engineering and society. She earned her PhD in Management Science & Engineering at Stanford.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/94056849008
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, October 29, 2025 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
Data Science Nights - October 2025 - Speaker: Buduka Ogonor, Physics and Astronomy
Northwestern Institute on Complex Systems (NICO)
5:30 PM
//
Lower Level, Chambers Hall
Details
OCTOBER MEETING: Thursday, October 30, 2025 at 5:30pm (US Central)
LOCATION:
In person: Chambers Hall, Lower Level
600 Foster Steet, Evanston Campus
AGENDA:
5:30pm - Meet and greet with refreshments
6:00pm - Talk with Buduka Ogonor, Motter Group, Department of Physics and Astronomy, Center for Network Dynamics
TALK TITLE:
Finding gene sets underlying complex phenotypes via generative modeling
ABSTRACT:
Most human traits are complex, that is, they emerge from the interactions among multiple genes. The sheer number of possible gene set-to-phenotype mappings makes it challenging to identify the gene sets underlying complex traits using statistical approaches like genome and transcriptome-wide association studies. Furthermore, these existing approaches assume that molecular-level changes are independent, which is at odds with the existence of intracellular networks that govern cell behavior.
Here, we present an approach that identifies gene set-to-phenotype relationships that leverages generative modeling trained on publicly available transcriptional data. We use a generative model—dubbed TWAVE for Transcription-Wide Variational Auto-Encoder—to emulate diseased and healthy transcriptional states. Then, we use existing transcriptional measurements of responses to turning genes on and off as inputs to an optimization framework, which identifies the gene perturbations that minimize the transcriptional difference between the diseased and healthy states. Using nine disease traits as examples, we show that the approach identifies causal genes that cannot be detected by the primary existing techniques. We suggest that the approach be used to design tailored experiments to identify multi-genic targets to address complex diseases.
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
Time
Thursday, October 30, 2025 at 5:30 PM - 7:30 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Julio M. Ottino, Northwestern University "From Clocks to Clouds: The Complexity Revolution"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Julio M. Ottino, Walter P. Murphy Professor of Chemical and Biological Engineering, McCormick School of Engineering, Northwestern University
Title:
From Clocks to Clouds: The Complexity Revolution: How Scientific Breakthroughs Reshaped Reality and Our Place Within It
Abstract:
For three centuries, Western thought was guided by a Newtonian worldview: the universe as a vast clock, predictable and controllable. That vision has unraveled. Scientific revolutions—from relativity and quantum mechanics to evolution, game theory, and complexity science—have revealed a world of uncertainty, emergence, and creative interconnection. We now inhabit a “cloud world,” where relationships matter more than parts, and uncertainty is not ignorance but potential. This talk traces the transformation from clocks to complexity, showing how these revolutions reshape our understanding of reality and what it means to navigate knowledge, organizations, and society in turbulent times.
Speaker Bio:
Julio M. Ottino is an engineering scientist recognized for his work in fluid dynamics, chaos and nonlinear dynamics, complex systems, and especially mixing. He was born in La Plata, Argentina and grew up with twin interests in the physical sciences and visual arts. He obtained his first degree at the University of La Plata, in Argentina, before receiving a PhD in chemical engineering from the University of Minnesota. He is currently at the McCormick School of Engineering and Applied Science in Northwestern University where he holds the titles of Robert R. McCormick Institute Professor and Walter P. Murphy Professor of Chemical and Biological Engineering. He is also a professor of Management and Organizations at Kellogg School of Management. He was the co-founder and director of the Northwestern Institute on Complex Systems (NICO) and the author of the Kinematics of Mixing: Stretching, Chaos, and Transport (Cambridge University Press 1989) and The Nexus, Augmented Thinking for a Complex World, with Bruce Mau (MIT Press, 2022).
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/99053647199
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, November 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: Blaise Aguera y Arcas, Google "Symbiogenesis, Computational Parallelism, and Complexity in Evolution"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Blaise Agüera y Arcas, VP/Fellow, CTO of Technology & Society, Google
Title:
Symbiogenesis, Computational Parallelism, and Complexity in Evolution
Abstract:
Symbiogenesis-- the fusion of formerly independent self-replicating entities into a larger self-replicating entity-- is proposed as the driving force behind evolution's "arrow of time" toward ever-increasing complexity. We'll explore an Artificial Life system as a minimal motivating example, then discuss the implications for biological evolution beyond the "standard" accounts of Major Evolutionary Transitions and "intelligence explosions" in brainy species. Energetic and computational implications will also be addressed.
Speaker Bio:
Blaise Agüera y Arcas is a VP and Fellow at Google, where he is the CTO of Technology & Society and founder of Paradigms of Intelligence (Pi). Pi is an organization working on fundamental research in AI and related fields, especially the foundations of neural computing, active inference, sociality, evolution, and Artificial Life.
In 2008, Blaise was awarded MIT’s TR35 prize. During his tenure at Google, Blaise has innovated on-device machine learning for Android and Pixel; invented Federated Learning, an approach to decentralized model training that avoids sharing private data; and founded the Artists + Machine Intelligence program.
An External Professor at Santa Fe Institute and a frequent public speaker, Blaise has given multiple TED talks and keynoted NeurIPS. He has also authored numerous papers, essays, op-eds, and chapters, as well as two previous books, Who Are We Now? and Ubi Sunt. His most recent book, What Is Life?, is part 1 of the larger book What Is Intelligence?, forthcoming from Antikythera and MIT Press in September 2025.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/98741396308
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, November 12, 2025 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
Data Science Nights - November 2025 - Speaker: Feihong Xu, ESAM
Northwestern Institute on Complex Systems (NICO)
5:30 PM
//
Lower Level, Chambers Hall
Details
NOVEMBER MEETING: Thursday, November 20, 2025 at 5:30pm (US Central)
LOCATION:
In person: Chambers Hall, Lower Level
600 Foster Steet, Evanston Campus
AGENDA:
5:30pm - Meet and greet with refreshments
6:00pm - Talk with Feihong Xu, Amaral Lab, ESAM
Talk title and abstract TBA.
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
Time
Thursday, November 20, 2025 at 5:30 PM - 7:30 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
Data Science Nights - December 2025 - Speaker: Yash Chainani, Chemical Engineering
Northwestern Institute on Complex Systems (NICO)
5:30 PM
//
Lower Level, Chambers Hall
Details
DECEMBER MEETING: Thursday, December 18, 2025 at 5:30pm (US Central)
LOCATION:
In person: Chambers Hall, Lower Level
600 Foster Steet, Evanston Campus
AGENDA:
5:30pm - Meet and greet with refreshments
6:00pm - Talk with Yash Chainani, Broadbelt & Tyo Labs, Chemical Engineering
Talk title and abstract TBA.
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
Time
Thursday, December 18, 2025 at 5:30 PM - 7:30 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)