Alexander Sietsema
I am currently on the job market! Please reach out if there is anything you would like to discuss.
I am a final year applied mathematics Ph.D. candidate at UCLA advised by Deanna Needell. My work focuses on the mathematical tools of data science and machine learning. As AI systems become an increasingly integral part of everyday life, understanding the way they behave is critical. My research analyzes how the structure of modern datasets, as well as the properties of the models we choose to learn from them, affect the performance of learning algorithms. I work to understand these properties mathematically, incorporate them into new, more effective learning methods, and apply them to interdisciplinary problems. I approach these problems using tools from high-dimensional probability, numerical linear algebra, and computational harmonic analysis, working across both theory and practice. See the Research section for more information.
I am originally from East Lansing, MI. Before starting at UCLA, I received a B.S. in Advanced Mathematics and a B.S. in Computational Mathematics from Michigan State University. See the Personal section for more details.
Recent News
September 2026: I have been awarded the UCLA Carolyn D. Smith Graduate Scholarship for future teachers!
May 2026: I have been selected as one of the recipients of the UCLA Department of Mathematics Dissertation Year Award for 2026-2027! I am grateful to the department for their recognition and support.
May 2026: I have been awarded the Liggett UCLA Math Department Teaching Award for 2026!
April 2026: Our paper “Harmful Overfitting in Sobolev Spaces” has been accepted to ICML 2026! I will be presenting in person in July at the conference in Seoul, South Korea.
April 2026: Our paper “VDW-GNNs: Vector diffusion wavelets for geometric graph neural networks” has been accepted to ICML 2026! I will be presenting in person in July at the conference in Seoul, South Korea.
April 2026: I will be participating in the University of British Columbia Women in Mathematics of Data Science Workshop! The workshop will take place from August 4-14 in Vancouver, BC, Canada.
April 2026: I will be speaking at the International Conference on Computational Harmonic Analysis at Vanderbilt University in May! The conference will be held from May 18-22 in Nashville, TN.
April 2026: I will be giving a talk at the Southern California Applied Mathematics Symposium at Loyola Marymount University in late April! I will be speaking about our recent work in harmful and benign overfitting in Sobolev spaces.