A common real-life problem is to fairly allocate a number of indivisible objects and a fixed amount of money among a group of agents. Fairness requires that each agent weakly prefers his consumption bundle to any other agent's bundle. In this context, fairness is incompatible with budget-balance...

A time bank is a group of individuals and/or organizations in a local community that set up a common platform to trade services among themselves. There are several well-known problems associated with this type of banking, e.g., high overhead costs for record keeping and difficulties to identify...

A set of indivisible objects is allocated among agents with strict preferences. Each object has a weak priority ranking of the agents. A collection of priority rankings, a priority structure, is solvable if there is a strategy-proof mechanism that is constrained efficient, i.e. that always...