Recent studies say prices change every four months. Economists have interpreted this high frequency as evidence against the importance of sticky prices for the monetary transmission mechanism. Theory implies that if most price changes are regular, as they are in the standard New Keynesian model,...

We present a pricing kernel that summarizes well the main features of the dynamics of interest rates and risk in postwar U.S. data and use it to uncover how the pricing kernel has moved with the short rate in this data. Our findings imply that standard monetary models miss an essential link...

In standard approaches to monetary policy, interest rate rules often lead to indeterminacy. Sophisticated policies, which depend on the history of private actions and can differ on and off the equilibrium path, can eliminate indeterminacy and uniquely implement any desired competitive...

The optimal choice of a monetary policy instrument depends on how tight and transparent the available instruments are and on whether policymakers can commit to future policies. Tightness is always desirable; transparency is only if policymakers cannot commit. Interest rates, which can be made...

In the data, prices change both temporarily and permanently. Standard Calvo models focus on permanent price changes and take one of two shortcuts when confronted with the data: drop temporary changes from the data or leave them in and treat them as permanent. We provide a menu cost model that...

We find conditions for the Friedman rule to be optimal in three standard models of money. These conditions are homotheticity and separability assumptions on preferences similar to those in the public finance literature on optimal uniform commodity taxation. We show that there is no connection...

How much discretion should the monetary authority have in setting its policy? This question is analyzed in an economy with an agreed-upon social welfare function that depends on the randomly fluctuating state of the economy. The monetary authority has private information about that state. In the...

We analyze the setting of monetary and nonmonetary policies in monetary unions. We show that in these unions a time inconsistency problem in monetary policy leads to a novel type of free- rider problem in the setting of nonmonetary policies, such as labor market policy, fiscal policy, and bank...

This paper analyzes the effects of money injections on interest rates and exchange rates in a model in which agents must pay a Baumol-Tobin style fixed cost to exchange bonds and money. Asset markets are endogenously segmented because this fixed cost leads agents to trade bonds and money only...

Is the exchange rate or the money growth rate the better instrument of monetary policy? A common argument is that the exchange rate has a natural advantage because it is more transparent: it is easier for the public to monitor than the money growth rate. We formalize this argument in a simple...