We first observe that two of Maskin’s results do not extend beyond three players: we construct a four-player partition function with nonpositive externalities whose unique solution is inefficient, as well as a four-player characteristic function that has a unique efficient solution for each...

For games in partition function form, we explore the implications of distinguishing between the concepts of intrinsic marginal contributions and externalities. If one requires efficiency for the grand coalition, we provide several results concerning extensions of the Shapley value. Using the...

We first observe that two of Maskin's results do not extend beyond three players: we construct a four-player partition function with nonpositive externalities whose unique solution is inefficient, as well as a four-player characteristic function that has a unique efficient solution for each...

What is common to the following situations: incentivizing collective action in the presence of social preferences, monopoly pricing when consumers are loss averse, arms races when players are privately informed of their armament costs? We present a simple formalism, called X-games, which unifies...

What is common to the following situations: designing random incentive schemes to implement team effort, monopoly pricing when consumers are loss averse, arms races when players are privately informed of their armament costs? We present a simple formalism, called X-games, which captures these...