Kaie Kubjas

Kaie Kubjas

Assistant Professor

Aalto University

Biography

Since 2017 I am a tenure-track assistant professor in the Department of Mathematics and Systems Analysis at Aalto University. I received my PhD in mathematics in 2013 from Freie Universität Berlin under supervision of Christian Haase and Klaus Altmann. As a postdoctoral researcher I visited Max Planck Institute for Mathematics, Aalto Science Institute, Simons Institute for the Theory of Computing, Institute of Data, Systems and Society at MIT and PolSys Team at Sorbonne University.

I work in the field of applied nonlinear algebra. I am particularly interested in algebraic statistics and applications in biology, for example in phylogenetics and 3D genome reconstruction. I am also interested in questions about matrix and tensor decompositions, e.g. nonnegative and positive semidefinite factorizations, and low-rank matrix/tensor completion. Besides nonlinear algebra, I like to use tools from combinatorics, polyhedral geometry and convex optimization.

Currently I am the Vice Chair of the SIAM Activity Group on Algebraic Geometry. In 2020-2022 I was the Deputy Convenor of European Women in Mathematics.

Academy of Finland is funding my research through project funding for early-career researchers.

Interests
  • Algebraic statistics
  • Nonlinear algebra in biology
  • Structured matrix and tensor decompositions
Education
  • PhD in Mathematics, 2013

    Free University of Berlin

  • BSc in Mathematics, 2007

    University of Tartu

Editorial and organizatorial work

News

Exact Solutions in Log-Concave Maximum Likelihood Estimation
Our paper with Alexandros Grosdos, Alexander Heaton, Olga Kuznetsova, Georgy Scholten, and Miruna-Stefana Sorea is now published in Advances in Applied Mathematics. The log-concave maximum likelihood estimate is known to be the exponential of a tent function with the tentpoles being the data points. The tent function induces a subdivision of the convex hull of the data points. It turns out that even determining the optimal subdivision can be challenging! We study the transcendentality of the solutions, give a closed form solution in the simplest case and explore how to certify the solutions.
European Women in Mathematics General Meeting 2022
The European Women in Mathematics General Meeting 2022 took place at Aalto University during August 22-26, 2022. The conference had 129 participants from 25 countries. Click on the post to read more.
European Women in Mathematics General Meeting 2022
Applied Algebra Session at the Nordic Congress of Mathematicians
The 28th Nordic Congress of Mathematicians took place at Aalto University during August 18-21, 2022. Together with Elisenda Feliu (University of Copenhagen) and Cordian Riener (UiT The Arctic University of Norway), we organized the Applied Algebra Session that brought together applied algebraists in the Nordic countries. The list of talks in the session can be found here.
The model-specific Markov embedding problem for symmetric group-based models
Together with my PhD student Muhammad Ardiyansyah and Dimitra Kosta we study the model specific embedding problem for symmetric group-based models in phylogenetics. We provide a characterisation of model embeddable Markov matrices corresponding to symmetric group-based phylogenetic models. Our paper is published in the Journal of Mathematical Biology.
Olga Kuznetsova wins Second Place Poster Award at MEGA 2021
My PhD student Olga Kuznetsova won shared Second Place Poster Award at MEGA 2021 for her poster Algebraic Degree of Optimization Over a Variety. The poster is based on our recent preprint Algebraic degree of optimization over a variety with an application to p-norm distance degree together with Olga Kuznetsova and Luca Sodomaco. Congratulations, Olga!

Contact

  • P.O. Box 11100
    FI-00076 Aalto
  • Visiting address: Room Y237, Otakaari 1, 02150 Espoo