I study a market where agents with jointly owned heterogeneous goods trade subject to the constraint that each agent ends up with one good. In this market the existence of an efficient, incentive compatible, individually rational and budget balanced mechanism depends on the shares of the agents....

We study chip-strategy equilibria in two-player repeated games. Intuitively, in these equilibria players exchange favors by taking individually suboptimal actions if these actions create a "gain" for the opponent larger than the player's "loss" from taking them. In exchange, the player who...