Giannis Fikioris

Gates Hall 336

Ithaca, New York State

I am a final-year PhD student in the theory group at Cornell University and very fortunate to be advised by Éva Tardos. My PhD has been supported by the NDSEG fellowship, the Onassis Scholarship, and the Google PhD fellowship. I am broadly working on Algorithmic Game Theory and Learning Theory problems. My most recent work has been on Mechanism Design and/or Online Learning with global constraints.

Starting March 2025, I’ve been a part-time Student Researcher at Google Research in the Market Algorithms team working with Yuan Deng, Balu Sivan, and Renato Paes Leme. During Fall 2023, I was a Student Researcher in the Market Algorithms team at Google Research. This internship led to No-Regret Algorithms in non-Truthful Auctions with Budget and ROI Constraints, published with Mingfei Zhao and Gagan Aggarwal.

Before coming to Cornell, I received my BSE from the department of Electrical and Computer Engineering at the National Technical University of Athens. I completed my undergraduate thesis with Dimitris Fotakis, titled Perturbation Stability for Mechanism Design.

From July 2019 to August 2020, I was working at NCSR “Demokritos” in the Complex Event Recognition Group, advised by Alexander Artikis.

How to pronounce my name.

This year I am on the job market,
looking for postdocs and positions in industry!

News

Oct 2025	Robust Equilibria in Shared Resource Allocation via Strengthening Border’s Theorem accepted to SODA 2026!
May 2025	Learning in Budgeted Auctions with Spacing Objectives accepted to EC 2025!
May 2025	Beyond Worst-Case Online Allocation via Dynamic Max-min Fairness accepted to EC 2025!
Apr 2025	Online Resource Sharing: Better Robust Guarantees via Randomized Strategies accepted to IJCAI 2025!
Mar 2025	Starting this semester I will be a part-time Student Researcher at Google Research!

Selected Publications

EC 25

Learning in Budgeted Auctions with Spacing Objectives

Giannis Fikioris, Robert Kleinberg, Yoav Kolumbus, Raunak Kumar, Yishay Mansour, and Éva Tardos

EC 2025, ACM Conference on Economics and Computation

LINK PDF Bib

@inproceedings{DBLP:conf/sigecom/FikiorisKKKMT25,
  author = {Fikioris, Giannis and Kleinberg, Robert and Kolumbus, Yoav and Kumar, Raunak and Mansour, Yishay and Tardos, Éva},
  editor = {Ashlagi, Itai and Roth, Aaron},
  title = {Learning in Budgeted Auctions with Spacing Objectives},
  booktitle = {EC 2025, ACM Conference on Economics and Computation},
  pages = {158},
  publisher = {{ACM}},
  year = {2025},
  url = {https://doi.org/10.1145/3736252.3742512},
  biburl = {https://dblp.org/rec/conf/sigecom/FikiorisKKKMT25.bib},
  bibsource = {dblp computer science bibliography, https://dblp.org},
  arixv = {2411.04843},
  link = {https://dl.acm.org/doi/10.1145/3736252.3742512},
}

EC 25

Beyond Worst-Case Online Allocation via Dynamic Max-min Fairness

Giannis Fikioris, Siddhartha Banerjee, and Éva Tardos

EC 2025, ACM Conference on Economics and Computation

LINK PDF Bib

@inproceedings{DBLP:conf/sigecom/FikiorisBT25,
  author = {Fikioris, Giannis and Banerjee, Siddhartha and Tardos, Éva},
  editor = {Ashlagi, Itai and Roth, Aaron},
  title = {Beyond Worst-Case Online Allocation via Dynamic Max-min Fairness},
  booktitle = {EC 2025, ACM Conference on Economics and Computation},
  pages = {92},
  publisher = {{ACM}},
  year = {2025},
  url = {https://doi.org/10.1145/3736252.3742501},
  biburl = {https://dblp.org/rec/conf/sigecom/FikiorisBT25.bib},
  bibsource = {dblp computer science bibliography, https://dblp.org},
  arixv = {2310.08881},
  link = {https://dl.acm.org/doi/10.1145/3736252.3742501},
}

EC 23

Math of OR

Liquid Welfare Guarantees for No-Regret Learning in Sequential Budgeted Auctions

Giannis Fikioris and Éva Tardos

Mathematics of Operations Research (accepted 2024)
EC 2023, ACM Conference on Economics and Computation

LINK PDF Bib

@article{DBLP:journals/mor/FikiorisT25,
  author = {Fikioris, Giannis and Tardos, Éva},
  title = {Liquid Welfare Guarantees for No-Regret Learning in Sequential Budgeted Auctions},
  journal = {Mathematics of Operations Research (accepted 2024)<br>EC 2023, ACM Conference on Economics and Computation},
  volume = {50},
  number = {2},
  pages = {1233--1249},
  year = {2024},
  url = {https://doi.org/10.1287/moor.2023.0274},
  biburl = {https://dblp.org/rec/journals/mor/FikiorisT25.bib},
  bibsource = {dblp computer science bibliography, https://dblp.org},
  arixv = {2210.07502},
  link = {https://pubsonline.informs.org/doi/10.1287/moor.2023.0274},
  abbr2 = {Math of OR}
}