Separation of Unit of Account from Medium of Exchange

Abstract

The separation of a unit of account (UoA) from a medium of exchange (MoE) in the commodity–money system is investigated by considering explicitly a seller's choice of UoA in terms of either an MoE or a unit of metal weight. If the likelihood of debasement of an MoE and its rate are high enough, the price is posted in terms of a unit of metal weight rather than an MoE. Interestingly, this MoE–UoA separated equilibrium yields the flexible nominal price, whereas an MoE–UoA integrated equilibrium yields the sticky one. This implies the nominal price rigidity in the fiat‐money system where MoE and UoA are integrated.