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arXiv · 1705.10116

Fractional Hedonic Games

Haris Aziz·Florian Brandl·Felix Brandt·Paul Harrenstein·Martin Olsen·Dominik Peters
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Abstract

The work we present in this paper initiated the formal study of fractional hedonic games, coalition formation games in which the utility of a player is the average value he ascribes to the members of his coalition. Among other settings, this covers situations in which players only distinguish between friends and non-friends and desire to be in a coalition in which the fraction of friends is maximal. Fractional hedonic games thus not only constitute a natural class of succinctly representable coalition formation games, but also provide an interesting framework for network clustering. We propose a number of conditions under which the core of fractional hedonic games is non-empty and provide algorithms for computing a core stable outcome. By contrast, we show that the core may be empty in other cases, and that it is computationally hard in general to decide non-emptiness of the core.

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Haris Aziz, Florian Brandl, Felix Brandt, Paul Harrenstein, Martin Olsen, Dominik Peters. 2017-05-29. Fractional Hedonic Games. https://arxiv.org/abs/1705.10116

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