Contact info

Job e-mail: apostolos.chalkis@quantagonia.com

Secondary e-mail: tolis.chal@gmail.com

Status

Since April 2022, I work at Quantagonia as Research Engineer. I am developing Optimization, Simulation, and Artificial Intelligence models and their implementations for today’s high-performance computers, and for later use on quantum computers via Quantagonia’s new Quantum Virtual Platform.

My complete CV can be found here.

Profile and interests

My research focuses on geometric random walks and sampling for financial modeling, volume computation, and convex optimization. In particular, my research interests are:

  • Mathematical optimization.

  • Markov Chain Monte Carlo sampling methods for high dimensional multivariate distributions.
  • Portfolio scoring, portfolio optimization, and anomaly detection in big stock markets.
  • Bayesian statistics.
  • Optimized implementation of state-of-the-art randomized, geometric and statistical algorithms.

I am also an open-source programmer. I have participated in Google Summer of Code 2018 and 2019 as a student. I am the author and maintainer of packages volesti and dingo. I am also a co-founder of GeomScale org, an open research, and development project that delivers open-source code at the intersection of data science, geometric, and statistical computing.

Research & Industrial internships

  • OLZ Asset Managment. I developed randomized, geometric algorithms for low volatility anomaly detection in big stock markets, Oct. ‘21 - Apr. ‘22.
  • Tweag - Software innovation lab. I built the python package dingo to analyze metabolic networks with Markov Chain Monte Carlo algorithms, Feb. ‘21 - May ‘21.
  • ATHENA RC & Ansys Greece Collaboration. I provided reports and prototype software benchmarking results for potential improvements on Ansys’ Random Walk Technology, Nov. ‘20 - Jun. ‘21.
  • Google Summer of Code 2019. State-of-the-art geometric random walks for sampling from high dimensional bodies in R, May ‘19 - Aug. ‘19.
  • Google Summer of Code 2018. State-of-the-art algorithms in R for volume computation and sampling in high dimensions, May ‘18 - Aug. ‘18.
  • PeGASUS project (ATHENA RC & EU Fund). Approximate geometric algorithms and clustering with applications in finance, May ‘20 - Aug. ‘21.

Education

  • 2022: PhD in Computer Science, NKUA.

    Title: Efficient geometric random walks for high-dimensional sampling from convex bodies and applications in finance.

    Advisor: Prof. Ioannis Z. Emiris.

  • 2018: MSc in Computer Science, NKUA.

    Specialization: Theoretical Computer Science.

    Master’s thesis in Computational Geometry,

    Title: Practical Volume Computation of Structured Convex Bodies for Modeling Financial Crises,

    Advisor: Prof. Ioannis Z. Emiris.

  • 2016: Graduate from School of Applied Mathematics and Physics (5 years degree), NTUA.

    Specialization: Applied Mathematics.

    Thesis in Numerical Linear Algebra,

    Title: Numerical algorithms for eigenvalue and singular value decomposition,

    Advisor: Prof. Konstantinos Chrysafinos.