Optimal sequential decision architectures and the robustness of hierarchies and polyarchies

This paper studies collective decision making in the context of a project selection model. We derive the optimal decision architecture when marginal decision costs are present, and investigate the circumstances under which the hierarchy and polyarchy exist as optimal sequential architectures. Our analysis extends previous results on optimal committee decision-making to a sequential setting, and further demonstrates the fragility of the hierarchy and polyarchy as optimal architectures. JEL Classification number: D81