Multilisting for Horizontally Differentiated Services: Implications for Throughput and Social Welfare

When Joining More Queues Is Not Always Better When customers can join multiple wait lists, does more choice always improve a service system? In “Multilisting for Horizontally Differentiated Services: Implications for Throughput and Social Welfare,” Chen, Ding, and Yang study customers who can join several provider queues, choose only their preferred provider, or decline service. The authors compare this flexible multilisting design with single-listing and pooling. Multilisting attracts more customers and consistently achieves at least as much throughput as either alternative. It also improves social welfare relative to pooling. Yet compared with single-listing, the extra participation can worsen congestion and reduce welfare, even as access expands. The analysis further shows that the welfare-maximizing allocation may treat otherwise identical providers asymmetrically, and that nonnegative, asymmetric prices can steer customers toward socially efficient choices. The findings offer guidance for designing healthcare wait lists, public housing systems, vaccination programs, and other capacity-constrained services where access, matching, and congestion must be balanced.