Year: 2025
Type: article
Abstract: Coalition formation is concerned with the question of how to partition a set of agents into disjoint coalitions according to their preferences. Deviating from most of the previous work, we consider an online variant of the problem, where agents arrive in sequence. Whenever an agent arrives, they must be assigned to a coalition immediately and irrevocably. The scarce existing literature on online coalition formation has focused on maximizing social welfare, a demanding requirement, even in the offline setting. Instead, we seek to achieve stable coalition structures online and treat the most common stability concepts based on deviations by single agents and groups of agents. We present a comprehensive picture in additively separable hedonic games, leading to dichotomies, where positive results are obtained by deterministic algorithms and negative results even hold for randomized algorithms.
DOI: 10.1613/jair.1.16420
Authors: Martin Bullinger, René Romen
Institutions: University of Oxford, Technical University of Munich
Language: English
Subfield: Economics and Econometrics
Domain: Social Sciences
Open Access status: diamond
Awards: G6255747833, G7405528578
OpenAlex ID: W4409790455