Iosif Sakos

Research Fellow at Singapore University of Technology and Design (SUTD)

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My name is Iosif (aka Joseph). I am a Research Fellow in Engineering Systems and Design at SUTD funded by the Centre for Quantum Technologies (CQT) via the CQT++ Core Research Funding Grant. My research focuses on optimization for classical and quantum AI, and lies at the intersection of algorithmic game theory and Sum-of-Squares optimization.

Research Overview

I develop optimization-based methods with certifiable guarantees, using the Sum-of-Squares (SOS) framework and semidefinite programming, to make learning and strategic decision-making reliable.

Multi-agent problems are often structured. For example:

  • Extensive-form games are polynomial games in the space of behavioral strategies.
  • Learning dynamics often satisfy positive correlation; that is, strategy updates align with payoff improvements instantaneously.

The SOS framework allows us to exploit or enforce such structures to obtain strong certificates, e.g., the existence and uniqueness of Nash equilibria. It can also be used to identify and steer learning dynamics towards desirable outcomes, even when data are scarce or expensive to acquire.

More recently, I have been working on quantum optimization, in particular on tractable relaxations and provable approximation schemes for training parametrized quantum circuits (PQCs).

Teaching Overview

I am actively involved in both undergraduate and graduate teaching in optimization, game theory, and learning in games at SUTD.

  • I currently serve as a Teaching Fellow for the undergraduate course Optimization.
  • In Fall 2025, I served as a Teaching Fellow for Special Topics in Games, Learning, and Optimization (with Anas Barakat and John Lazarsfeld), for which we developed a complete course website.
  • In Spring 2025, I was a co-facilitator for Optimization for Data Science (with Antonios Varvitsiotis).

Across courses, I emphasize mathematical rigor, conceptual clarity, and the unifying role of optimization in learning and strategic interaction. I design and deliver hands-on, student-centered learning through interactive Python and Julia lab sessions, and I am committed to fostering an inclusive, supportive learning environment for all students.