Events
Past Event
WED@NICO SEMINAR: Momin Malik, Harvard University "Revisiting 'All Models are Wrong': Addressing Limitations in Big Data, Machine Learning, and Computational Social Science"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
![Momin Malik](
https://planitpurple.northwestern.edu/uploads/image_sm/162434_sm.jpg)
Speaker:
Momin Malik - Data Science Postdoctoral Fellow, Berkman Klein Center for Internet & Society, Harvard University
Title:
Revisiting "All Models are Wrong": Addressing Limitations in Big Data, Machine Learning, and Computational Social Science
Abstract:
In the immortal words of George E. P. Box (1979), "All models are wrong, but some are useful." This is an important lesson to recall amidst hopes and claims that digital trace data, the high-dimension and low-assumption models of machine learning, and advancements in computational social science are overcoming the limitations of the past. In this talk, I review the fundamental limitations with which all quantitative research must grapple, and discuss how these limitations manifest today.
Larger data captures more heterogeneity and allows for studying finer and finer subpopulations and phenomena, but as I demonstrate with geotagged tweets, selection bias still makes results fail to generalize to larger populations. The platforms from which we gather data are not research utilities, and I model the introduction of Facebook's "People You May Know" recommender system to show how social media platforms' efforts to solicit desirable behavior from users changes what we think we observe. Through considering co-location data via mobile phone sensors versus friendship self-report, I consider how new forms of measurement do not necessarily supersede previous forms but capture different underlying constructs that can be fruitful opportunities for research. I conclude with a theoretical overview of limitations of forms of quantitative modeling, from the inevitable reliance on central tendencies in probability-based modeling through to how cross-validation can break down in the presence of dependencies.
This talk will serve as a useful overview about modeling limitations and critiques, as well as possible fixes, for researchers in and practitioners of data science, computational social science, social physics, statistics, and machine learning. It will also be useful as a primer for those outside these fields on the appropriate and inappropriate uses of techniques from them.
Speaker Bio:
Momin M. Malik is the Data Science Postdoctoral Fellow at the Berkman Klein Center for Internet & Society at Harvard University. He holds an undergraduate degree in history of science from Harvard, a master’s from the Oxford Internet Institute, and a master's in Machine Learning and a PhD in Societal Computing from the School of Computer Science, Carnegie Mellon University, where his dissertation measured how much social media platform effects, demographic biases, and reliance on mobile phone sensor data can threaten generalizability of findings in computational social science. His current work bridges machine learning and science studies to understand the sources of both success and failures in machine learning.
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.
Live Stream:
Time
Wednesday, February 5, 2020 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Simbarashe Nkomo, Emory University "Exploring the Emergence of Complex Dynamics in Networks of Belousov-Zhabotinsky Oscillators"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
![Simbarashe Nkomo](
https://planitpurple.northwestern.edu/uploads/image_sm/190324_sm.jpg)
Speaker:
Simbarashe Nkomo, Assistant Professor of Chemistry, Oxford College of Emory University
Title:
Exploring the Emergence of Complex Dynamics in Network of Belousov-Zhabotinsky (BZ) Oscillators
Abstract:
The study of complex systems permeates diverse scientific domains and engineering applications. Through the lens of a nonlinear chemical oscillator, the Belousov-Zhabotinsky (BZ) reaction, we explore the occurrence of complex behaviors in small and large oscillator networks. Using both experiments and theoretical models, we demonstrate the role of coupling strength, coupling mode, initial conditions, and system heterogeneities in the emergence of complex dynamics such as mixed periods, period cycling, and chimera states. We use phase response curves to provide mechanistic insight into how the oscillators’ phases during interactions contribute to the onset of complex dynamics. Our results show that even slight perturbations with correct timing of phases can cause the system to transit from periodic oscillations to more complex behaviors. These studies offer potential strategies for controlling complex dynamics in other real-world applications such as neuronal networks.
Speaker Bio:
Simbarashe (Simba) Nkomo is Assistant Professor of Chemistry at Emory University (Oxford College). His research interests are in chemical nonlinear dynamics, specifically on complex synchronization dynamics in experimental and theoretical BZ models, and chemical predictive toxicity models. Simba has research published in Nature Physics, Physical Review Letters, and Chaos: An Interdisciplinary Journal of Nonlinear Science.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/97359095225
Passcode: NICO2024
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, April 24, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
NICO AI Seminar: Ziv Epstein, Stanford University "Re-Inventing the Attention Machine"
Northwestern Institute on Complex Systems (NICO)
1:00 PM
//
Lower Level, Chambers Hall
Details
![Ziv Epstein](
https://planitpurple.northwestern.edu/uploads/image_sm/190467_sm.jpg)
Speaker:
Ziv Epstein, Postdoctoral Fellow, Stanford Institute for Human-Centered AI, Stanford University
Title:
Re-Inventing the Attention Machine
Abstract:
Modern AI systems - such as LLMs and feed algorithms on social media - are algorithmic amplifiers that uplift certain voices and perspectives. But whose perspectives? In this talk, I will argue that human attention is the key bridge to understanding how we shape these AI amplifiers and how they shape us. In particular, I will argue that AI systems are training on a particular ground truth that is mediated by human attention and as a result is hill-climbing on attentional noise. To what extent is training data transformed by attention? Can we measure it? And can we shift attention to make more deliberate training data? I will discuss ways to measure attentional drift in AI systems, as well as prosocial tools to align behavior and values, and ongoing attempts to embed values into these AI amplifiers explicitly. These projects point to a new way of designing sociotechnical systems for prosocial outcomes, by moving away from attention economies and towards attention ecologies.
Speaker Bio:
Ziv Epstein is a Postdoctoral Fellow at the Stanford Institute for Human-Centered AI. In his research, he focuses on translating insights from design and the social sciences into the development of sociotechnical systems such as generative AI and social media platforms. Ziv has published papers in venues such as the general interest journals Nature, Science and PNAS , as well as top-tier computer science proceedings such as CHI and CSCW. His work has also received widespread media attention in outlets like the New York Times, Scientific American, and NPR.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/98518429787
Passcode: NICO2024
Calendar:
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About this Seminar:
NICO welcomes everyone to join us at this AI focused Thursday afternoon seminar. Please note, since this is at 1pm, we will provide light refreshments only.
Time
Thursday, April 25, 2024 at 1:00 PM - 2:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Chris Bail, Duke University "Bridging Divides with Generative AI"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
![Chris Bail](
https://planitpurple.northwestern.edu/uploads/image_sm/190325_sm.jpg)
Speaker:
Chris Bail, Professor of Sociology, Political Science, and Public Policy, Duke University
Title:
Bridging Divides with Generative AI
Abstract:
Political discourse is the soul of democracy, but misunderstanding and conflict can fester in divisive conversations. The widespread shift to online discourse exacerbates many of these problems and corrodes the capacity of diverse societies to cooperate in solving social problems. Scholars and civil society groups promote interventions that make conversations less divisive or more productive, but scaling these efforts to online discourse is challenging. This talk will describe a large-scale experiment that demonstrates how online conversations about divisive topics can be improved with AI tools. Specifically, my colleagues and employ a large language model to make real-time, evidence-based recommendations intended to improve participants’ perception of feeling understood. These interventions improve reported conversation quality, promote democratic reciprocity, and improve the tone, without systematically changing the content of the conversation or moving people’s policy attitudes. These findings replicate during a half year experiment on a large social media platform.
Speaker Bio:
Chris Bail is Professor of Sociology, Political Science, and Public Policy at Duke University, where he founded the Polarization Lab. He studies how artificial intelligence shapes human behavior in a range of different settings—and social media platforms in particular. Chris is passionate about building the field of computational social science. He is the Editor of the Oxford University Press Series in Computational Social Science and the Co-Founder of the Summer Institutes in Computational Social Science. Chris received his PhD from Harvard University in 2011.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/97722631639
Passcode: NICO2024
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, May 1, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Daniel Harris, Brown University "At the interface: physical analogy with interfacial fluid mechanics"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
![Daniel Harris](
https://planitpurple.northwestern.edu/uploads/image_sm/190326_sm.jpg)
Speaker:
Daniel Harris, Assistant Professor of Engineering, Brown University
Title:
At the Interface: Physical Analogy with Interfacial Fluid Mechanics
Abstract:
Maxwell describes physical analogy as a "partial similarity between the laws of one science and those of another which makes each of them illustrate the other." Hydrodynamics has long since been a source of physical analogy, sharing similar equations with other seemingly disparate fields of physics. The focus of this talk will be on physical analogies with interfacial fluid systems, where accessible tabletop experiments can be used to investigate and communicate physical phenomena at vastly different scales. Following a brief review of some historical examples of analogy in interfacial fluid mechanics, I will describe two recent tabletop experiments developed in our lab that share similarities with certain microscopic colloidal systems. While physical analogy can be fruitfully used to advance science across disciplines, it can also be leveraged to enhance scientific communication and pedagogy.
Speaker Bio:
Daniel M. Harris is an Assistant Professor of Engineering at Brown University in the Fluids and Thermal Sciences group. Before joining Brown, Dan was a Postdoctoral Research Associate and Lecturer at the University of North Carolina at Chapel Hill in the Department of Mathematics. Dan received his B.S. in Mechanical Engineering from Cornell University in 2010 and his Ph.D. in Applied Mathematics from MIT in 2015.
Dan’s primary research interests are in interfacial phenomena, microfluidics, and transport phenomena. His research involves an integrated experimental and theoretical approach. Dan has also received numerous awards for his scientific visualizations, including being selected as the winner of the 2016 NSF/Popular Science Visualization Challenge in Photography, as well as numerous prizes from the American Physical Society’s Gallery of Fluid Motion and Gallery of Soft Matter.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/93585934682
Passcode: NICO2024
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, May 8, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Eleni Katifori, University of Pennsylvania "TBA"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
![Eleni Katifori](
https://planitpurple.northwestern.edu/uploads/image_sm/190327_sm.jpg)
Speaker:
Eleni Katifori, Associate Professor, Department of Physics & Astronomy, University of Pennsylvania
Title:
TBA
Abstract:
TBA
Speaker Bio:
Eleni Katifori is an Associate Professor in the Department of Physics & Astronomy, University of Pennsylvania. Prof Katifori’s research group are interested in understanding the physics behind the morphological and functional attributes of living organisms. They primarily focus on questions inspired by and related to biological transport networks and the elasticity and geometry of thin sheets. Professor Katifori received her Ph.D from Harvard University in 2008 and a B.S. from the University of Athens, Greece in 2002.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/92857810876
Passcode: NICO2024
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, May 15, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Serguei Saavedra, MIT "How Do Ecological Systems Become (re)Assembled?"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
![Serguei Saavedra](
https://planitpurple.northwestern.edu/uploads/image_sm/190329_sm.jpg)
Speaker:
Serguei Saavedra, Associate Professor, Department of Civil and Environmental Engineering, MIT
Title:
How Do Ecological Systems Become (re)Assembled?
Abstract:
One of the most iconic thought experiments in biology is what would happen if we could rewind the tape of life on Earth and play it again. Would the tape have a different story in every replay? Or is there a general order of events? The relevance of this thought experiment is not just philosophical or counterfactual, because (re)assembly processes undergone by ecological systems, from microbes to mega-fauna, are continuously replicating the experiment. By integrating theoretical and empirical work, in this talk I will provide a guideline to increase our understanding about the (re)assembly possibilities of ecological systems. Explaining and predicting the (re)assembly of ecological systems underpins our ability to develop successful interventions in bio-restoration, bio-technologies, and bio-medicine.
Speaker Bio:
Serguei Saavedra is an Associate Professor at MIT in the Department of Civil and Environmental Engineering. He is also an external faculty at Santa Fe Institute. Serguei is a theoretical ecologist focused on understanding the feasibility of observing the emergence, transformations, and regeneration of ecological systems under environmental changes. Before joining MIT in 2016, Serguei studied systems engineering in Mexico; specialized in mathematical modeling at Genoa University; completed his PhD in engineering science at Oxford University; and did his postdoctoral work at the NICO (under the mentorship of Brian Uzzi), Doñana Biological Station, and in the department of environmental systems at ETH.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/91082510906
Passcode: NICO2024
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, May 22, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Joseph Paulsen, Syracuse University "TBA"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
![Joseph Paulsen](
https://planitpurple.northwestern.edu/uploads/image_sm/190328_sm.jpg)
Speaker:
Joseph Paulsen, Associate Professor, Department of Physics, Syracuse University
Title:
TBA
Abstract:
TBA
Speaker Bio:
Joseph Paulsen earned a bachelor's degrees in Mathematics and Physics from St. Olaf College in Northfield, MN, and he completed his PhD in Physics at the University of Chicago with Sidney Nagel. He won a National Science Foundation CAREER Award for his work that studies connections between geometry and mechanics in thin materials. Outside of science, one of his passions is trying to squirrel away as much time as possible to ski with his 7-year-old daughter (his son and his wife are not skiers... yet).
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/94291553667
Passcode: NICO2024
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, May 29, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)