Events
Past Event
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
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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)
Data Science Nights - MAY 2026 - Speaker: Xudong Tang, Computer Science and NICO
Northwestern Institute on Complex Systems (NICO)
5:30 PM
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M416, Technological Institute
Details
MAY MEETING: Thursday, May 28, 2026 at 5:30pm (US Central)
LOCATION:
ESAM Conference Room, Tech M416
2145 Sheridan Road, Evanston, IL 60208
AGENDA:
5:30pm - Meet and greet with refreshments
6:00pm - Talk with Xudong Tang, PhD Student, Computer Science, NICO, and the Human-AI Collaboration Lab, Northwestern University
TALK TITLE:
Human and Machine Perception of Voice Similarity
ABSTRACT:
Modern voice cloning systems generate synthetic speech that listeners frequently cannot identify as being synthetic. But a voice can sound natural without sounding like the intended person, and what determines whether a clone is heard as a particular person is an open question. Here we report a large-scale preregistered experiment in which we collected 92,239 responses from 175 participants on their perception of pairs of real recordings, voice clones, and continuously morphed voices drawn from 100 contemporary celebrities across 20 speaker groups. We find that voice clones do not reliably preserve perceived speaker identity, reducing same-speaker judgments by 12.7 percentage points even though the clones are produced by a state-of-the-art text-to-speech model, while leaving different-speaker judgments unchanged. Using continuously morphed stimuli, we find that speakers vary substantially in how much variation their perceived identity tolerates, and that this variation is not predicted by speaker demographics. Speaker embeddings account for 58.9\% (95\% CI = [55.7, 61.9]) of variance in identity judgments, which is more than acoustic features, social attributes, and clone status combined. Once all these observed features are accounted for, clone status adds no additional predictive power. These results shows that the perceptual impact of voice cloning is positional rather than categorical: we can model how listeners judge a voice by how close it falls to the perceptual boundary that defines each speaker's recognizable voice, applying the same criterion to real and synthetic speech alike.
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 return in September!
Time
Thursday, May 28, 2026 at 5:30 PM - 7:00 PM
Location
M416, Technological Institute Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
Spring 2026 Commencement
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All Day
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Spring 2026 Commencement
Time
Sunday, June 14, 2026
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Juneteenth - University Closed
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Juneteenth - University Closed
Time
Friday, June 19, 2026
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Independence Day (observed) - University Closed
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Independence Day (observed) - University Closed
Time
Friday, July 3, 2026
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Fall 2026 Classes Begin
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Fall 2026 Classes Begin
Time
Wednesday, September 23, 2026
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