Teaching

Machine Learning and Computational Complexity, Fall 2025

This Bachelor’s seminar explores the computational foundations of machine learning. We study the theoretical principles that govern the power and limits of learning algorithms, from data requirements and model complexity to computational hardness and interactive learning protocols.

Large Language Models, Spring 2026

Large language models have become one of the most commonly deployed NLP inventions. In the past half-decade, their integration into core natural language processing tools has dramatically increased the performance of such tools, and they have entered the public discourse surrounding artificial intelligence. In this course, we start with the probabilistic foundations of language models, i.e., covering what constitutes a language model from a formal, theoretical perspective. We then discuss how to construct and curate training corpora, and introduce many of the neural-network architectures often used to instantiate language models at scale. The course discusses privacy and harms, as well as applications of language models in NLP and beyond.

Advanced Formal Language Theory, Spring 2022

This course serves as an introduction to various advanced topics in formal language theory. The primary focus of the course is on weighted formalisms, which can easily be applied in machine learning. Topics include finite-state machines as well as the algorithms that are commonly used for their manipulation. We will also cover weighted context-free grammars, weighted tree automata, and weighted mildly context-sensitive formalisms.

Advanced Formal Language Theory, Spring 2023

This course serves as an introduction to various advanced topics in formal language theory. The primary focus of the course is on weighted formalisms, which can easily be applied in machine learning. Topics include finite-state machines as well as the algorithms that are commonly used for their manipulation. We will also cover weighted context-free grammars, weighted tree automata, and weighted mildly context-sensitive formalisms.

Advanced Formal Language Theory, Spring 2024

This course serves as an introduction to various advanced topics in formal language theory. The primary focus of the course is on weighted formalisms, which can easily be applied in machine learning. Topics include finite-state machines as well as the algorithms that are commonly used for their manipulation. We will also cover weighted context-free grammars, weighted tree automata, and weighted mildly context-sensitive formalisms.

Advanced Formal Language Theory, Spring 2025

This course explores the connection between automata and formal logic. More precisely, it covers the algebraic characterization of the regular languages definable in many different logical theories, the complexity theory of boolean circuits, and the connection between the two.

COLING 2022

The *Information Theory in Linguistics* course focuses on the application of information-theoretic methods to natural language processing, emphasizing interdisciplinary connections with the field of linguistics.

Dependency Structures and Lexicalized Grammars

This seminar explores a variety of algorithms for efficient dependency parsing and their derivatioin in a unified algebraic framework.

ESSLLI 2021

The *Information Theory in Linguistics* course focuses on the application of information-theoretic methods to natural language processing, emphasizing interdisciplinary connections with the field of linguistics.

Formal Language Theory and Neural Networks

This tutorial is a comprehensive introduction to neural network language models, focusing on those based on recurrent neural networks (RNNs) and Transformers (Vaswani et al., 2017), and their relationship to formal language theory. We teach how tools from weighted formal language theory can be useful for understanding the inner workings of and predicting the generalization of modern neural architectures. Over the course of five days, we will explore the theoretical properties of RNNs and their representational capacity in relation to different levels of the weighted Chomsky hierarchy, starting with finite-state automata and the special case of bounded-depth hierarchical languages, and then move on to more complex formalisms such as context-free languages and Turing machines. We will prove multiple theoretical properties of RNNs, including the fact that simple RNNs with infinite precision arithmetic and unbounded computation time can emulate a Turing machine and show how RNNs can optimally represent finite-state automata. We will also discuss recent results in the study of Transformer-based language models from the perspective of formal language theory. Finally, we will discuss the implications of these results for the analysis and practical deployment of language models.