Game-Theoretic Solutions for Constrained Geo-Social Event Organization

Abstract

In Geo-Social Event Organization (GSEO), each user of a geo-social network is assigned to an event, so that the distance and social costs are minimized. Specifically, the distance cost is the total distance between every user and his assigned event. The social cost is measured in terms of the pairs of friends in different events. Intuitively, users should be assigned to events in their vicinity, which are also recommended to their friends. Moreover, the events may have constraints on the number of users that they can accommodate. GSEO is an NP-Hard problem. In this paper, we utilize a game-theoretic framework, where each user constitutes a player that wishes to minimize his own social and distance cost. We demonstrate that the Nash Equilibrium concept is inadequate due to the capacity constraints, and propose the notion of pairwise stability, which yields better solutions. In addition, we develop a number of optimization techniques to achieve efficiency. Our experimental evaluation on real datasets demonstrates that the proposed methods always outperform the state-of-the-art in terms of solution quality, while they are up to one order of magnitude faster.