In this paper we study the relation between convexity of TU games and marginal vectors.We show that if specfic marginal vectors are core elements, then the game is convex.We characterize sets of marginal vectors satisfying this property, and we derive the formula for the minimum number of...

In this paper we review, and draw some lessons from, the UMTS-auctions that have taken place in Europe during 2000 and 2001.We address several design issues and, in particular, focus attention on asymmetries between the bidders and on possibilities for collusion.An outlook is provided to several...

We consider a firm's decision to replace an existing production technology with a new, more cost-efficient one.Kulatilaka and Perotti [1998, Management Science] nd that, in a two-period model, increased product market uncertainty could encourage the firm to invest strategically in the new...

In this paper we generalize the concept of a non-transferable utility game by introducing the concept of a socially structured game.A socially structured game is given by a set of players, a possibly empty collection of internal organizations on any subset of players, for any internal...

We consider cooperative games with transferable utility (TU-games), in which we allow for a social structure on the set of players, for instance a hierarchical ordering or a dominance relation.The social structure is utilized to refine the core of the game, being the set of payoffs to the...