I am a Lecturer (Assistant Professor) in the School of Computer Science and Electronic Engineering at the University of Essex. I am also a member of the Artificial Intelligence group and the Centre for Computational Finance and Economic Agents.
Previously, I was a post-doctoral researcher in the group of Operations Research at TU Munich, headed by Prof. Andreas S. Schulz.
Prior to this, I was a short-term post-doctoral researcher in the Computer Science Department at the University of Liverpool.
I received my PhD from the Computer Science Department at the University of Liverpool, where I was fortunate to be supervised by Prof. Paul Spirakis.
My undergraduate degree is in Electrical and Computer Engineering from the University of Patras.
My research interests mainly revolve around Algorithmic Game Theory. I also enjoy working in Computational Social Choice and in the intersection of Theoretical Computer Science and Economics. I study the computational complexity and also exact/approximation algorithms of problems in these fields.
A full list of publications and manuscripts can be found on DBLP and Google Scholar.
Conference papers
Constant Inapproximability for Fisher Markets (proceedings, video)
EC 2024, 25th ACM Conference on Economics and Computation
with Argyrios Deligkas, John Fearnley, and Alexandros Hollender
On the Smoothed Complexity of Combinatorial Local Search (proceedings, arXiv)
ICALP 2024, 51st International Colloquium on Automata, Languages, and Programming
with Yiannis Giannakopoulos, and Alexander Grosz
Optimization of Trading Strategies Using a Genetic Algorithm Under the Directional Changes Paradigm with Multiple Thresholds (proceedings)
CEC 2023, IEEE Congress on Evolutionary Computation
with Ozgur Salman, and Michael Kampouridis
Tight Inapproximability for Graphical Games (proceedings, arXiv)
AAAI 2023, 37th AAAI Conference on Artificial Intelligence
with Argyrios Deligkas, John Fearnley, and Alexandros Hollender
Pure-Circuit: Strong Inapproximability for PPAD (proceedings, arXiv, video)
FOCS 2022, 63rd Annual Symposium on Foundations of Computer Science
with Argyrios Deligkas, John Fearnley, and Alexandros Hollender
Constant Inapproximability for PPA (proceedings, arXiv, video)
STOC 2022, 54th Annual ACM Symposium on Theory of Computing
with Argyrios Deligkas, John Fearnley, and Alexandros Hollender
Pizza Sharing is PPA-hard (proceedings, arXiv, video)
AAAI 2022, 36th AAAI Conference on Artificial Intelligence
with Argyrios Deligkas, and John Fearnley
Walrasian Equilibria in Markets with Small Demands (proceedings, arXiv, video)
AAMAS 2021, 20th International Conference on Autonomous Agents and MultiAgent Systems
with Argyrios Deligkas, and Paul G. Spirakis
Connected Subgraph Defense Games (proceedings, arXiv)
SAGT 2019, 12th International Symposium on Algorithmic Game Theory
with Eleni C. Akrida, Argyrios Deligkas, and Paul G. Spirakis
Computing Exact Solutions of Consensus Halving and the Borsuk-Ulam Theorem (proceedings, arXiv)
ICALP 2019, 46th International Colloquium on Automata, Languages, and Programming
with Argyrios Deligkas, John Fearnley, and Paul G. Spirakis
Approximating the Existential Theory of the Reals (proceedings, arXiv, video)
WINE 2018, 14th International Conference on Web and Internet Economics
with Argyrios Deligkas, John Fearnley, and Paul G. Spirakis
Strategic Contention Resolution in Multiple Channels (proceedings, arXiv)
WAOA 2018, 16th International Workshop on Approximation and Online Algorithms
with George Christodoulou, and Paul G. Spirakis
Short Paper: Strategic Contention Resolution in Multiple Channels with Limited Feedback (proceedings, arXiv)
SAGT 2018, 11th International Symposium on Algorithmic Game Theory
with George Christodoulou, and Paul G. Spirakis
Mutants and Residents with Different Connection Graphs in the Moran Process (proceedings, arXiv)
LATIN 2018, 13th Latin American Symposium on Theoretical Informatics
with Sotiris E. Nikoletseas, Christoforos L. Raptopoulos, and Paul G. Spirakis
Existence of Evolutionarily Stable Strategies Remains Hard to Decide for a Wide Range of Payoff Values (proceedings, arXiv)
CIAC 2017, 10th International Conference on Algorithms and Complexity
with Paul G. Spirakis
Journal papers
A Genetic Algorithm for the Optimization of Multi-Threshold Trading Strategies in the Directional Changes Paradigm
(to appear) Artificial Intelligence Review 2025
with Ozgur Salman, and Michael Kampouridis
On the Smoothed Complexity of Combinatorial Local Search (article)
MOR 2025, Mathematics of Operations Research
with Yiannis Giannakopoulos, and Alexander Grosz
Pizza Sharing is PPA-hard (article)
ToCT 2025, ACM Transactions on Computation Theory
with Argyrios Deligkas, and John Fearnley
Constant Inapproximability for PPA (article)
SICOMP 2025, SIAM Journal on Computing
with Argyrios Deligkas, John Fearnley, and Alexandros Hollender
Pure-Circuit: Tight Inapproximability for PPAD (article)
JACM 2024, Journal of the ACM, Volume 71, Issue 5, Article 31
with Argyrios Deligkas, John Fearnley, and Alexandros Hollender
Approximating the Existential Theory of the Reals (article)
JCSS 2022, Journal of Computer and System Sciences, Volume 125: 106-128
with Argyrios Deligkas, John Fearnley, and Paul G. Spirakis
An Extension of the Moran Process Using Type-specific Connection Graphs (article)
JCSS 2022, Journal of Computer and System Sciences, Volume 124: 77-96
with Sotiris E. Nikoletseas, Christoforos L. Raptopoulos, and Paul G. Spirakis
Connected Subgraph Defense Games (article)
Algorithmica 2021
with Eleni C. Akrida, Argyrios Deligkas, and Paul G. Spirakis
Computing Exact Solutions of Consensus Halving and the Borsuk-Ulam Theorem (article)
JCSS 2021, Journal of Computer and System Sciences, Volume 117: 75-98
with Argyrios Deligkas, John Fearnley, and Paul G. Spirakis
Surveys
Multi-Agent Systems for Computational Economics and Finance (article, arXiv)
AI Communications 2022, Volume 35, no. 4, pp. 369-380
with Michael Kampouridis, Panagiotis Kanellopoulos, Maria Kyropoulou, and Alexandros A. Voudouris
International Conference on Autonomous Agents and Multiagent Systems (AAMAS) 2025
European Conference on Artificial Intelligence (ECAI) 2024, 2025
International Joint Conference on Artificial Intelligence (IJCAI) 2021, 2022, 2023, 2024
Conference on Artificial Intelligence (AAAI) 2020, 2023, 2024, 2025
International Symposium on Algorithmic Game Theory (SAGT) 2022, 2023, 2025
Conference on Web and Internet Economics (WINE) 2025
Conferences: CIAC, OPODIS, WALCOM, IWOCA, NETYS, PODC, DISC, WINE, SAGT, ALENEX, LATIN, ICALP, AAMAS, STACS, SODA, STOC
Journals: Random Structures & Algorithms, AMS Mathematical Reviews, Theoretical Computer Science, Theory of Computing Systems, Mathematics of Operations Research, Information and Computation, ACM Transactions on Algorithms, SIAM Journal on Computing
Conferences: SAGT 2016, MFCS 2018
Teaching Assistant at the University of Liverpool for the following courses:
COMP108: Data Structures and Algorithms (Spring '17-'18)
COMP109: Foundations of Computer Science (Fall '17-'18)
COMP202: Complexity of Algorithms (Spring '16-'17, '17-'18, '18-'19)
COMP219: Advanced Artificial Intelligence (Fall '18-'19)
COMP281: Principles of C and Memory Management (Spring '16-'17)
COMP323: Introduction to Computational Game Theory (Fall '16-'17, '17-'18, '18-'19)
Instructor at the University of Liverpool for the course:
COMP323: Introduction to Computational Game Theory (Fall '19-'20)
Teaching Assistant at TU Munich for the course:
MA5226: Special Topics in Algorithmic Game Theory (Fall '20-'21)
Co-organizer at TU Munich for the seminars:
Complexity of Total Search Problems (Spring '20-'21)
Fair Division: Algorithms, Complexity & Optimization (Fall '21-'22)
Module Supervisor at the University of Essex for the following courses:
CE903: Group Project (Spring '23-'24)
CF962: Quantitative Methods in Finance and Trading (Autumn '22-'23, '24-'25)
CF963: Computational Models in Economics and Finance (Spring '24-'25)
CF966: Financial Engineering and Risk Management (Spring '22-'23, '23-'24)
Address: Office 5A.544, School of CSEE, Colchester campus, CO4 3SQ
Email: themistoklis dot melissourgos at essex dot ac dot uk