We generalize exactness to games with non-transferable utility (NTU). A game is exact if for each coalition there is a core allocation on the boundary of its payoff set. Convex games with transferable utility are well-known to be exact. We consider five generalizations of convexity in the NTU...

In this paper, we consider the competition of a monopolistic provider of information products against a peer-to-peer file-sharing network that offers illegal versions of the products. We focus on the role of direct externalities caused by the P2P file-sharing technology rather than the indirect...