Trading Time in a Congested Environment

The first in, first out (FIFO) queue discipline respects the order of arrivals, but is not efficient when customers have heterogeneous waiting costs. Priority queues, in which customers with higher waiting costs are served first, are more efficient but usually involve undesirable queue-jumping behaviors that violate bumped customers’ property rights over their waiting spots. To have the best of both worlds, we propose time-trading mechanisms, in which customers who are privately informed about their waiting costs mutually agree on the ordering in the queue by trading positions. If a customer ever moves back in the queue, she will receive an appropriate monetary compensation. Customers can always decide not to participate in trading and retain their positions as if they are being served FIFO. We design the optimal mechanisms for the social planner, the service provider, and an intermediary who might mediate the trading platform. Both the social planner’s and the service provider’s optimal mechanisms involv...