Events
Past Event
WED@NICO WEBINAR: Lightning Talks with Northwestern Fellows and Scholars!
Northwestern Institute on Complex Systems (NICO)
12:00 PM
Details
Description:
NICO is hosting a lightning talk seminar each term as a part of our Wednesdays@NICO seminar series. Northwestern graduate students and postdoctoral fellows are invited to participate. To sign up for future lightning talks, please visit: https://bit.ly/2lRqSXK
Webinar:
Webinar link: https://northwestern.zoom.us/j/96018513447
Passcode: nico
ID: 960 1851 3447
Speakers:
Jaehyuk Park
Postdoctoral Fellow
Kellogg School of Managmeent, and
Northwestern Institute on Complex Systems
Emma Zajdela
PhD Candidate
Department of Engineering Sciences and Applied Mathematics
McCormick School of Engineering
Gary Nave
Postdoctoral Fellow
Department of Engineering Sciences and Applied Mathematics
McCormick School of Engineering
Sarah Ben Maamar
Postdoctoral Fellow
Department of Chemical and Biological Engineering
McCormick School of Engineering
Talk Titles and Abstracts:
Jaehyuk Park "People, Places, and Ties: Landscape of social places and their social network structures"
Due to their essential role as places for socialization, “third places”—social places where people casually visit and communicate with friends and neighbors—have been studied by a wide range of fields including network science, sociology, geography, urban planning, and regional studies. However, the lack of a large-scale census on third places kept researchers from systematic investigations. Here we provide a systematic nationwide investigation of third places and their social networks, by using Facebook pages. Our analysis reveals a large degree of geographic heterogeneity in the distribution of the types of third places, which is highly correlated with baseline demographics and county characteristics. Certain types of pages like “Places of Worship” demonstrate a large degree of clustering suggesting community preference or potential complementarities to concentration. We also found that the social networks of different types of social place differ in important ways: The social networks of ‘Restaurants’ and ‘Indoor Recreation’ pages are more likely to be tight-knit communities of pre-existing friendships whereas ‘Places of Worship’ and ‘Community Amenities’ page categories are more likely to bridge new friendship ties. We believe that this study can serve as an important milestone for future studies on the systematic comparative study of social spaces and their social relationships. This is joint work with Bogdan State (scie.nz), Monica Bhole (Facebook), Michael Bailey (Facebook), and Yong-Yeol Ahn (Indiana Univ.).
Emma Zajdela "Catalyzing Collaborations: A Model for the Dynamics of Team Formation at Conferences"
The COVID-19 pandemic has brought to the fore the importance of collaboration among scientists to address challenges of global significance. One of the main ways that new and innovative collaborations are catalyzed is by gathering scientists together at conferences. In the U.S. alone, conferences amount to billions of dollars per year in terms of travel expenses, organizing costs, and loss of research time. In this lightning talk, I present a dynamical model for predicting the formation of scientific collaborations at conferences, inspired by the chemical process of catalysis. Specifically, the model tracks the probability that two participants at a conference will form a collaboration given their previous knowledge of each other and level of interaction throughout the conference. Model predictions are tested using data from two multi-year series of interactive conferences known as the Scialog Conferences, organized by the Research Corporation for Science Advancement over the period 2015-2020. We find that scientists who interact more intensely throughout the conference have a higher likelihood of forming a collaboration. Furthermore, we find that the likelihood of collaborating remains at a higher level even after the interaction between participants has ceased. Our findings may have an impact on stakeholders from public, private, and nonprofit sectors who wish to optimize future conferences to promote new collaborations.
Gary Nave "Approximating attracting and repelling flow features with the trajectory divergence rate"
Within the flow of a fluid or a dynamical system, there are often attracting or repelling manifolds that provide an organizing “skeleton” to the flow. These structures have been shown to be barriers to transport of material moving within a flow. In this talk, I will introduce the trajectory divergence rate, which can serve to rapidly approximate attracting and repelling structures using only the vector field. By looking at the instantaneous growth rate of normal vectors, we measure the rate at which adjacent trajectories are coming together or moving apart. This diagnostic can be applied to, for example, slow manifolds, ocean flows, and limit cycle oscillations, and provides an intuitive understanding of the geometric organization of a flow.
Sarah Ben Maamar "Comprehensive analysis of the reproducibility of RNAseq computational pipelines"
Sarah Ben Maamar, Reese Richardson, Sophia Liu, Luis Nunes A. Amaral.
Next generation sequencing technologies revolutionized biomedical research and became unavoidable due to their low costs, high amount of data generated and the wide variety of their applications. In particular, RNA-sequencing (RNA-seq) has become widely used in biological and biomedical fields as this technique allows the evaluation of gene expression levels in model organisms under different contexts. These contexts include the comparison of sick versus healthy cells; the effect of specific drugs on cells gene expression; monitoring of changes in gene expression over time; or the discovery of the potential role of an unknown gene when comparing different tissues.
As the output of RNA-seq is complex and large, processing and analysis of such data requires the use of complex computational pipelines involving multiple steps and softwares to make the data comprehensible. RNA-seq computational pipelines vary according to the application and can have up to six steps, for which up to ten different softwares are available for each task. Each software also offers multiple parameters to better tune the analysis for each application and dataset.
Despite the endless choices, there is currently no standardized pipeline agreed upon in the broad biomedical field. Thus, unless a computational pipeline used to process a dataset is thoroughly documented, it is almost impossible to reproduce the results obtained from a dataset after processing.
In this work, we analyze the documentation and replicability associated to each step of RNA-seq computational pipelines used to study differential gene expression in the model bacteria Escherichia coli. We particularly assess the intrinsic bias introduced by the use of each software for each step as well as the bias associated to each parameter choice. Interestingly, we found two to three steps of RNA-seq computational pipeline are particularly undermining the comparability of the results between studies. We are currently in the process of quantifying the biases at each step of the different computational pipelines and this talk will present some of our results.
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, March 3, 2021 at 12:00 PM - 1:00 PM
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Ágnes Horvát, Northwestern University "Science on the Web: How networks bias academic communication online"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Ágnes Horvát - Assistant Professor, Communication Studies, School of Communication, Northwestern University
Title:
Science on the Web: How networks bias academic communication online
Abstract:
Most academics are promoting their work online. At the same time, the public, journalists, and interested governments increasingly turn to the Web for scientific information. It thus becomes ever more critical that we better understand the dynamics of online science dissemination networks. My talk presents our latest results about (1) how scientific publications spread on various types of online platforms, losing essential information; (2) how gender and ethnic inequalities impact the coverage of scholarship; and (3) how subsequently retracted articles receive more attention online. Our findings highlight crucial biases in the online sharing of science. They inform efforts to close gaps in scholars' success and curb the online spread of science-related misinformation.
Speaker Bio:
Ágnes Horvát is an Assistant Professor in Communication and Computer Science (by courtesy) at Northwestern University, where she directs the Technology and Social Behavior PhD program. Her research lies at the intersection of computational social science, social computing, and communication. Using interdisciplinary approaches from network and data science, her research group, the Lab on Innovation, Networks, and Knowledge (LINK), investigates how networks induce biased information production, sharing, and processing on digital platforms. For example, they study the impact of networks and diversity on scholarly communication, identify expressions of collective intelligence and opportunities for innovation in crowdsourcing communities, and develop tools to support creativity and predict success in culture industries. Professor Horvát received her PhD in Physics from the University of Heidelberg, Germany.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/95881985279
Passcode: NICO23
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, February 8, 2023 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Yong-Yeol "YY" Ahn, Indiana University Bloomington "Science of science, law of law, and patterns of patents: universal citation dynamics in knowledge systems"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Yong-Yeol "YY" Ahn, Associate Professor, Center for Complex Networks and Systems Research, Luddy School of Informatics, Computing, and Engineering, Indiana University Bloomington
Title:
Science of science, law of law, and patterns of patents: universal citation dynamics in knowledge systems
Abstract:
Citation is a fundamental way for humans to acquire and expand on existing knowledge. Although many laws and regularities of citation dynamics have been discovered from scientific citations, it is unclear whether and to what extent these regularities are inherent in how humans seek, use, and create knowledge. We show that, despite many stark differences between these systems, the citation dynamics in science, law, and patents share universal patterns. Given the differences in procedure and incentives that exist between judges, inventors, and scientists, our findings suggest that universal citation dynamics may be innate to any cumulative human knowledge system. Our model demonstrates that the evolution of collective attention and a handful of fundamental mechanisms can produce observed universal patterns of citation dynamics.
Speaker Bio:
Yong-Yeol (YY) Ahn is an Associate Professor at Indiana University School of Informatics, Computing, and Engineering. He was a Visiting Professor at MIT during 2020-2021. Before joining Indiana University, he worked as a postdoctoral research associate at the Center for Complex Network Research at Northeastern University and as a visiting researcher at the Center for Cancer Systems Biology at Dana-Farber Cancer Institute after earning his PhD in Statistical Physics from KAIST in 2008. His research focuses on developing network science and machine learning methods, and applying them to complex social and biological systems. He is a recipient of several awards including Microsoft Research Faculty Fellowship and LinkedIn Economic Graph Challenge.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/93818374439
Passcode: NICO23
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, February 15, 2023 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Chris Kuzawa, Northwestern University "Fetal developmental plasticity as signal-noise problem: the case of nutrients and stress physiology"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Chris Kuzawa, John D. MacArthur Professor, Department of Anthroplogy, Northwestern University
Title:
Fetal developmental plasticity as signal-noise problem: the case of nutrients and stress physiology
Abstract:
The stage of human development marked by greatest sensitivity and developmental plasticity occurs prior to birth, when the developing embryo and fetus are embedded within the highly regulated intrauterine environment maintained by the mother’s body. In this talk, I will discuss the timescales of maternal experience that modify this milieu, with a focus on two crucial systems: nutrient metabolism and stress physiology. I will argue that elaborate and redundant maternal buffering of nutrient delivery uncouples short term variability in what the mother eats – whether negative changes like famine or improvements in the form of nutritional supplementation - from fetal nutrition and development, which instead track changes in maternal nutrition on a longer, generational timescale. In contrast, stress physiology is by design highly responsive to the mother’s short-term experiences and the responsiveness of these systems have broad spill-over effects on fetal development, thus linking offspring biological and health outcomes to acute variability in maternal stress during pregnancy. I will discuss the relevance of these principles for understanding the evolution of the flow of ecological information across generations and the design of interventions aimed at harnessing early life plasticity to improve future population health.
Speaker Bio:
Chris Kuzawa and his students and collaborators use principles from anthropology and evolutionary biology to gain insights into the biological and health impacts of human developmental plasticity. Thier primary field research is conducted in Cebu, the Philippines, where they work with a large birth cohort study that enrolled more than 3,000 pregnant women in 1983 and has since followed their offspring into adulthood (now 30 years old). They use the nearly 3 decades of data available for each study participant, and recruitment of generation 3 (the grandoffspring of the original mothers), to gain a better understanding of the long-term and intergenerational impacts of early life environments on adult biology, life history, reproduction, and health. A theme of much of this work is the application of principles of developmental plasticity and evolutionary biology to issues of health. Professor Kuzawa is a member of the National Academy of Sciences and American Academy of Arts and Sciences.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/91503621521
Passcode: NICO23
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, February 22, 2023 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 Abrams, Northwestern University "Tractable mathematical modeling of social systems: some successes and failures"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Daniel Abrams, Professor of Engineering Sciences and Applied Mathematics and (by courtesy) Physics and Astronomy, Northwestern University
Title:
Tractable mathematical modeling of social systems: some successes and failures
Abstract:
TBA
Speaker Bio:
Daniel Abrams has broad scientific interests ranging from coupled oscillators to mathematical geoscience to the physics of social systems. He tries to approach these wide-ranging problems by creating greatly simplified mathematical models where rigorous analysis is possible, hopefully capturing some essential properties of the system. The work in different fields is generally connected by similar mathematical techniques drawn from the study of nonlinear dynamics.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/98183822887
Passcode: NICO23
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, March 1, 2023 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Alina Arseniev-Koehler, Purdue University "Stigma's Uneven Decline"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Alina Arseniev-Koehler, Assistant Professor, Sociology, Purdue University
Title:
Stigma’s Uneven Decline
Abstract:
Has the stigma targeting diseases declined? We analyze 4.7 million news articles to create new measures of stigma for 106 health conditions from 1980-2018, using word embedding methods for text analysis. We then examine how this stigma changed for different types of conditions across time using mixed effects regression modeling. We find that in the 1980s, most diseases were marked by strong connotations of disgust, immorality, and negative personality traits. Since then, stigma declined dramatically for chronic illnesses: cancers, neurological conditions, genetic diseases, and many other conditions have shed most of their negative connotations. But for other types of conditions, stigma proved especially resistant to change. Across the decades, behavioral health conditions (mental illnesses, addictions, and eating disorders) persistently connoted immorality and negative personality traits. Infectious diseases remained strongly linked to attributions of disgust. Stigma has transformed from a sea of negative connotations surrounding most diseases to a narrower set of judgments targeting conditions where the primary symptoms are aberrant behaviors. (This talk is based on research with Rachel Best at the University of Michigan).
Speaker Bio:
Alina Arseniev-Koehler is a computational and cultural sociologist with substantive interests in language, health, and social categories. Alina strives to clarify core concepts and debates about cultural meaning in sociology. For example, how do individuals learn and deploy stereotypes? Empirically, Alina focuses on cases where meaning is linked to inequality and health, such as the moral meanings attached to body weight, the stigmatizing meanings of disease, and gender stereotypes. To investigate these topics, Alina uses computational methods and machine learning, especially computational text analysis.
Alina’s work also circles around a methodological question: how can scientists measure meanings encoded in text data, such as news articles and social media posts? Computational text analysis requires scientists to mathematically model the nuanced ways in which human language encodes and conveys meaning. As highlighted by Alina’s work, innovation in computational text analysis is tightly intertwined with innovation in theoretical understanding of meanings.
Alina received a B.A. in Sociology from University of Washington in 2014, and a master’s and Ph.D. in Sociology from the University of California, Los Angeles in 2022.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/91034727443
Passcode: NICO23
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, March 8, 2023 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)