At the ACM CHI Conference on Human Factors in Computing Systems (CHI 2026)—the world’s leading conference in the field of human-computer interaction—Julien Gori (Sorbonne University), Aurelien Nioche (University of Glasgow), Christoph A. Johns (University of Oldenburg), and Antti Oulasvirta (Aalto University) were honored with the prestigious Best Paper Award for being among the top 1% of accepted research papers. Their paper, “A decision-theoretic representation of assistive interfaces,” addresses a fundamental gap in the development of assistive systems.

While adaptive interfaces, recommendation services, and intelligent assistants are ubiquitous in computer science, there has been a lack of a common conceptual foundation across different disciplines. In their paper, the authors present a formal model that describes assistance as a sequential decision-making process under uncertainty between two agents—the user and the assistant.

The research, which was also conducted as part of AAI postdoc Christoph A. Johns’ dissertation at Aarhus University, uses so-called Partially Observable Stochastic Games (POSGs) to mathematically capture interaction dynamics. For the first time, the model allows concepts such as adaptation, augmentation, and delegation to be mathematically defined and treats assistance as an optimization problem. In addition to the theoretical derivation, the researchers presented an implementation in the form of a Python library that enables the practical use of this framework.

Paper in ACM Digital Library: https://doi.org/10.1145/3772318.3791819