%0 Journal Article %J Algorithmica %D 2008 %T Cost-Sharing Mechanisms for Network Design %A Gupta,Anupam %A Srinivasan, Aravind %A Tardos,Éva %X We consider a single-source network design problem from a game-theoretic perspective. Gupta, Kumar and Roughgarden (Proc. 35th Annual ACM STOC, pp. 365–372, 2003 ) developed a simple method for a single-source rent-or-buy problem that also yields the best-known approximation ratio for the problem. We show how to use a variant of this method to develop an approximately budget-balanced and group strategyproof cost-sharing method for the problem. The novelty of our approach stems from our obtaining the cost-sharing methods for the rent-or-buy problem by carefully combining cost-shares for the simpler Steiner tree problem. Our algorithm is conceptually simpler than the previous such cost-sharing method due to Pál and Tardos (Proc. 44th Annual FOCS, pp. 584–593, 2003 ), and improves the previously-known approximation factor of 15 to 4.6. %B Algorithmica %V 50 %P 98 - 119 %8 2008/// %@ 0178-4617 %G eng %U http://dx.doi.org/10.1007/s00453-007-9065-y %N 1