LION 19: Learning and Intelligent Optimization Conference

The LION conference, held at Matfyz from June 15 to 19, 2025, focuses on connecting two key scientific areas: operations research, which addresses real-world optimization problems, with machine learning and artificial intelligence. The interconnection between artificial intelligence and optimization is bidirectional – machine learning algorithms are themselves based on optimization techniques, creating a strong symbiosis. The research area relevant to the conference is defined by the LION Manifesto.

As is traditional, invited speakers received a generous 100 minutes, allowing them to offer comprehensive tutorials and the latest insights from their respective fields. This year, four distinguished scientists delivered lectures. Carola Doerr (Sorbonne University) provided insights into the use of machine learning for automated selection of optimization algorithms. Maximilian Schiffer (Technical University of Munich) spoke about optimizing extended machine learning pipelines. Bissan Ghaddar (Ivey Business School) in her presentation detailed the use of machine learning techniques to improve polynomial optimization problems. Finally, Jakub Mareček (Czech Technical University) addressed the timely topic of fairness in repeated uses of AI systems.

A traditional feature of LION conferences is the absence of parallel sessions, allowing every participant to attend all lectures. Out of 70 submitted papers, 40 were accepted for oral presentation, each with a 20-minute slot; from 36 abstracts for the poster session, 26 were selected. Each poster author had one minute for an introductory „pitch“ followed by an intensive discussion.

The conference also awarded outstanding contributions. The main Best Paper Award was given to Zeno Woywood's collective for their lecture on autonomous vehicle fleet control. Two runner-up prizes were awarded for papers on solving the picker-routing problem and on whether Large Language Models (LLMs) understand constraint programming. The authors of the awarded papers received certificates and monetary prizes sponsored by Airbnb.

The local organization was shared by Milan Hladík from Matfyz and Hossein Moosaei from Jan Evangelista Purkyně University. LION 19 participants explored the historical Matfyz building, visited St. Wenceslas Rotunda from the 11th century, and enjoyed an afternoon musical performance by Cello Republic, a quartet of cellists known for their original arrangements and humor.

Alena Chrastová