Timing and real indeterminacy in monetary models

An increasingly common approach to the theoretical analysis of monetary policy ensures that a proposed policy does not introduce real indeterminacy—and thus sunspot fluctuations—into the model economy. Policy is typically conducted in terms of directives for the nominal interest rate. This paper uses a discrete-time, money-in-the-utility function model to demonstrate how seemingly minor modifications in the trading environment result in dramatic differences in the policy restrictions needed to ensure real determinacy. These differences arise because of the differing pricing equations for the nominal interest rate.