Stable and efficient task assignment to pairs
We study a model in which agents are matched in pairs in order to undertake a task and have preferences over both the partner and the task they are assigned to.
Every pair of agents has a set of tasks (possibly empty) that they mutually likes to perform together. Individual preferences are such that all partner-task pairs belong to three indifference class. In the topmost indifference class, there are the pairs in which an agent is matched with a partner and a commonly good task. The second class contains all the pairs in which the agent is matched with a partner with whom has some commonly good tasks, but the task they are assigned to does not belong to this set. Finally, the bottom class contains all pairs in which the agent is matched with someone with whom he has not any commonly good task.
We propose an algorithm that identifies a stable and Pareto efficient assignment. We also show that the procedure is strategy-proof and group strategy proof.