Alexandros Tsigonias-Dimitriadis

Alexandros Tsigonias-Dimitriadis

Economist, European Central Bank

Hi, I’m Alexandros!

I am an Economist at the Forecasting & Policy Modelling Division of DG Economics at the European Central Bank. I have five years of research experience in algorithms, game theory and mechanism design, and mathematical optimization, alongside three years of applied experience in data science and AI/ML engineering.

Before coming to the ECB, I was a postdoctoral researcher at the Department of Industrial Engineering of the University of Chile hosted by Prof. José Correa. I obtained my PhD from the Department of Mathematics of the TUM School of Computation, Information and Technology, where I was advised by Prof. Andreas S. Schulz and completed an interdisciplinary PhD program at the intersection of mathematics, computer science, and management science as a member of the research group AdONE. During my PhD and postdoc, I had the opportunity to spend some time at Google Research Zurich and the Sapienza University of Rome. I received my Diploma (BSc and MEng equivalent) in Electrical and Computer Engineering from the National Technical University of Athens, where I was advised by Prof. Dimitris Fotakis.

My research during my PhD and postdoc revolved mainly around the design of algorithms and mechanisms for fair and efficient resource allocation with applications in pricing, auctions, recommender systems, apportionment, and generally complex scenarios arising in (online) markets and platforms. I am now interested in the use of alternative data and the application of machine/deep learning techniques in macroeconomic forecasting.

You can find a copy of my CV here (last update: September 2026).

Interests
  • Economics and Computation
  • Operations Research & Optimization
  • AI & Machine Learning
  • Econometrics & Time Series Forecasting
  • Computational Social Science
Education

  • PhD in Mathematics, 2022

    Technical University of Munich

  • Diploma in Electrical and Computer Engineering, 2018

    National Technical University of Athens

News

  • [September 2026] I successfully completed the ECB Graduate Programme and started working as an economist at the Forecasting & Policy Modelling Division of DG Economics.

  • [September 2025] Our paper on monotone apportioment has been accepted for publication in Mathematics of Operations Research!

  • [June 2025] Our paper on the Prophet Secretary Against the Online Optimal has been accepted in Mathematics of Operations Research!

  • [February 2025] Check this very nice short article from MPI, where Javier talks about our SODA paper on apportionment.

  • [February 2025] Paper accepted in ACM TEAC.

  • [October 2024] Our paper on monotone apportionment methods will appear in SODA25!

  • [September 2024] I just started the ECB Graduate Programme!

  • [June 2024] The journal version of our paper “The Secretary Problem with Independent Sampling” has been published in Management Science! You can find it here. A big thank you to my co-authors for this wonderful collaboration!

  • [September 2023] Our paper with Tomer, Stefano, Rebecca, and Matteo has been accepted to WINE 2023!

  • [July 2023] I just started a new position at the European Central Bank!

  • [May 2023] I just started a research visit at Google Zurich hosted by Paul Dütting! I will be here for two months working on exciting algorithmic questions.

Journal Articles

Javier Cembrano, José Correa, Ulrike Schmidt-Kraepelin, Alexandros Tsigonias-Dimitriadis, Victor Verdugo (2025). New Combinatorial Insights for Monotone Apportionment. Articles in advance, Mathematics of Operations Research.

DOI

Paul Dütting, Evangelia Gergatsouli, Rojin Rezvan, Yifeng Teng, Alexandros Tsigonias-Dimitriadis (2025). Prophet Secretary Against the Online Optimal. Accepted, Mathematics of Operations Research.

José Correa, Andrés Cristi, Laurent Feuilloley, Tim Oosterwijk, Alexandros Tsigonias-Dimitriadis (2025). The Secretary Problem with Independent Sampling. Management Science.

DOI Paper Appendix

Tomer Ezra, Stefano Leonardi, Rebecca Reiffenhäuser, Matteo Russo, Alexandros Tsigonias-Dimitriadis (2025). Prophet Inequalities via the Expected Competitive Ratio. ACM Transactions on Economics and Computation (ACM TEAC).

DOI

Yiannis Giannakopoulos, Diogo Poças, Alexandros Tsigonias-Dimitriadis (2022). Robust Revenue Maximization Under Minimal Statistical Information. ACM Transactions on Economics and Computation (ACM TEAC).

Cite DOI arXiv

Conference Publications

Javier Cembrano, José Correa, Ulrike Schmidt-Kraepelin, Alexandros Tsigonias-Dimitriadis, Victor Verdugo (2025). New Combinatorial Insights for Monotone Apportionment. In the proceedings of the 2025 ACM-SIAM Symposium on Discrete Algorithms (SODA ‘25).

DOI arXiv MPI article

Tomer Ezra, Stefano Leonardi, Rebecca Reiffenhäuser, Matteo Russo, Alexandros Tsigonias-Dimitriadis (2023). Prophet Inequalities via the Expected Competitive Ratio. Extended abstract in the 19th Conference on Web and Internet Economics (WINE ‘23).

DOI arXiv slides

Paul Dütting, Evangelia Gergatsouli, Rojin Rezvan, Yifeng Teng, Alexandros Tsigonias-Dimitriadis (2023). Prophet Secretary Against the Online Optimal. In the proceedings of the 24th Conference on Economics and Computation (EC ‘23).

arXiv DOI poster

José Correa, Andrés Cristi, Laurent Feuilloley, Tim Oosterwijk, Alexandros Tsigonias-Dimitriadis (2021). The Secretary Problem with Independent Sampling. Extended abstract in the 2021 ACM-SIAM Symposium on Discrete Algorithms (SODA ‘21).

DOI arXiv slides poster

Yiannis Giannakopoulos, Diogo Poças, Alexandros Tsigonias-Dimitriadis (2020). Robust Revenue Maximization Under Minimal Statistical Information. Extended abstract in the 16th Conference on Web and Internet Economics (WINE ‘20).

DOI slides video

Working Papers & Manuscripts

José Correa, Émile Naquin, Nicolás Stier-Moses, Alexandros Tsigonias-Dimitriadis, Victor Verdugo (2026). A Simple Framework for Fairness of Exposure in Online Content Recommendation. Submitted.

Eleni Batziou, Giorgos Bouritsas, Alexandros Tsigonias-Dimitriadis (2023). Preference Elicitation in Combinatorial Auctions: An Improved Approach using Reinforcement Learning. Manuscript.

Teaching / Supervision

I have been a teaching assistant for the following courses:

I have co-supervised Master theses on the following topics:

  • Unified Voice or Cacophony? A Discordance Index of the European Central Bank Governing Council Members, ECB & Barcelona School of Economics
  • Iterative Combinatorial Auctions: Improved Running Time via Machine Learning, TUM
  • Experimental Evaluation of Robust Revenue-Maximizing Auctions, TUM

Contact