I am a fourth-year PhD student at Harvard, advised by Yaron Singer. I am part of the EconCS and the Harvard Machine Learning Theory groups.
My interests include Machine Learning, Algorithms and Optimization. Recently, I became interested in questions around neural networks. Specifically, why do our modern over-parametrized models generalize and what kind of theory do we need to develop to explain this phenomenon? Why are they susceptible to adversarial perturbations and how can we design more robust and interpretable models? For details please take a look at my publications.
Before coming to Harvard, I received my Bachelor's from the University of Athens where I was advised by Dimitris Fotakis. I worked in Algorithmic Game Theory and Selfish Routing.
I spent the summers of 2019 and 2020 in the Core Data Science team at Facebook working with Henry C. Lin, Smriti Bhagat and Udi Weinsberg. During the summer of 2018 I interned in Microsoft Research in Beijing (MSRA) hosted by Wei Chen.
My CV can be found here (last updated: June 2020).
Email: kalimeris [at] g [dot] harvard [dot] edu
Publications
Robustness from Simple Classifiers (working paper)
with Sharon Qian, Gal Kaplun and Yaron Singer
CLARA: Confidence of Labels and Raters
with Viet-An Nguyen, Peibei Shi, Jagdish Ramakrishnan, Udi Weinsberg, Henry C. Lin, Steve Metz, Neil Chandra, Jane Jing
26th International Conference on Knowledge Discovery and Data Mining, (KDD) 2020
SGD on Neural Networks Learns Functions of Increasing Complexity
with Preetum Nakkiran, Gal Kaplun, Tristan Yang, Benjamin L. Edelman, Fred Zhang and Boaz Barak
Annual Conference on Neural Information Processing Systems (NeurIPS) 2019
(spotlight presentation)
Preliminary version appeared in the 1st Workshop on Understanding and Improving Generalization in Deep Learning, ICML 2019
Robust Neural Networks are More Interpretable for Genomics
with Peter K. Koo, Sharon Qian, Gal Kaplun and Verena Volf
Preliminary version appeared in the ICML 2019 Workshop on Computational Biology
Robust Influence Maximization for Hyperparametric Models
with Gal Kaplun and Yaron Singer
International Conference of Machine Learning (ICML) 2019
Learning Diffusion using Hyperparameters
with Yaron Singer, Karthik Subbian and Udi Weinsberg
International Conference of Machine Learning (ICML) 2018
Improving Selfish Routing for Risk-Averse Players
with Dimitris Fotakis and Thanasis Lianeas
Web and Internet Economics (WINE) 2015
Committees
ICML 2020, NeurIPS 2020
Professional Experience
Summer 2020: Facebook Internship in Core Data Science group, NYC, hosted by Smriti Bhagat and Udi Weinsberg.
Summer 2019: Facebook Internship in Core Data Science group, Menlo Park, hosted by Henry C. Lin and Udi Weinsberg.
Summer 2018: MSR Asia Internship hosted by Wei Chen.
Summer 2014: Software Engineering internship at CERN, through CERN's summer student program.
Teaching Experience
Spring '19: AM 221: Advanced Optimization
Institution: Harvard
Instructor: Yaron Singer
Fall '17: CS 134: Networks (teaching excellence award)
Institution: Harvard
Instructor: Yaron Singer
Spring '16: Algorithmic game Theory
Institution: DIT
Instructor: Dimitris Fotakis
Fall '16: Mathematics for Computer Science, Theory of Computation
Institution: DIT
Instructor: Stavros Kolliopoulos