TechTalk – Speeding Up Fairness: The Science of Fast Convergence in Markets and Graphs

All members of the HKU community and the general public are welcome to join!
Speaker: Professor Hubert Chan, Associate Professor, School of Computing and Data Science, HKU
Date: 3rd April 2025 (Thursday)
Time: 4:30pm

Mode: Mixed

About the TechTalk
All members of the HKU community and the general public are welcome to join!
Speaker: Professor Hubert Chan, Associate Professor, School of Computing and Data Science, HKU
Moderator: Professor Weiming Feng, Assistant Professor, School of Computing and Data Science, HKU
Date:  3rd April 2025 (Thursday)
Time: 4:30pm
Mode: Mixed (both face-to-face and online). Seats for on-site participants are limited. A confirmation email will be sent to participants who have successfully registered.
Language: English

Achieving fairness in resource allocation can be modelled as a graph-based optimization problem, with many efficient algorithms available. This talk explores the connection between market equilibrium and graph density decomposition, showing how fast convergence can be achieved in large-scale systems. We present a unified framework linking hypergraph density decomposition and Fisher market equilibrium through locally verifiable optimality conditions. This symmetry allows repurposing algorithms between domains, significantly accelerating convergence.
We focus on iterative gradient-based methods, including the iterative proportional response process and its momentum-enhanced extensions. Our novel exponential momentum approach refines traditional techniques, delivering near-optimal solutions in distributed settings. Empirical results show these methods outperform existing algorithms, achieving speedups by several orders of magnitude in large-scale graphs.
By integrating graph theory, market dynamics, and optimization, this talk offers new insights into efficient computation to achieve fairness in networked systems. These methods deepen our understanding of algorithmic principles and open new applications in algorithm design, social networks, and economic modelling.

Registration
Registration
  • The tech talk “Speeding Up Fairness: The Science of Fast Convergence in Markets and Graphs” will be organized in the Tam Wing Fan Innovation Wing Two (G/F, Run Run Shaw Building, HKU) on 3rd April 2025 (Thursday), 4:30pm.
  • Seats are limited. Zoom broadcast is available if the seating quota is full. 
  • Registrants on the waiting list will be notified of the arrangement after the registration deadline (with seating/free-standing/other arrangement)
Recording of the Tech Talk
About the speaker

Professor Hubert Chan

Professor Hubert Chan completed his PhD in Computer Science at Carnegie Mellon University in 2007. Before taking up the faculty position at HKU in 2009, he spent two years as a post-doc at Max Planck Institute for Informatics in Germany. His main research interests are approximation algorithms, discrete metric space, privacy and security inspired problems.

Promotion materials
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Multifunctional Filters for Protecting Public Health

Clean water and clean air are vital for public health. This project focuses on developing high-efficiency and environmentally sustainable filters for removing harmful air/water pollutants. The team has developed novel architectures and functionalities for the filters to achieve high permeance, high removal efficiency, and excellent reusability.

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