Determinacy, Stock Market Dynamics and Monetary Policy Inertia

This note deals with the stability properties of an economy where the central bank is concerned with stock market developments. We introduce a Taylor rule reacting to stock price growth rates along with inflation and output gap in a New-Keynesian setup. We explore the performance of this rule from the vantage of equilibrium uniqueness. We show that this reaction function is isomorphic to a rule with an interest rate smoothing term, whose magnitude increases in the degree of aggressiveness towards asset prices growth. As shown by Bullard and Mitra (2007, Determinacy, learnability, and monetary policy inertia, Journal of Money, Credit and Banking 39, 1177-1212) this feature of monetary policy inertia can help at alleviating problems of indeterminacy.monetary policy; asset prices; rational expectation equilibrium uniqueness

Effects and Propositions

The quantum logical and quantum information-theoretic traditions have exerted an especially powerful influence on Bub's thinking about the conceptual foundations of quantum mechanics. This paper discusses both the quantum logical and information-theoretic traditions from the point of view of their representational frameworks. I argue that it is at this level, at the level of its framework, that the quantum logical tradition has retained its centrality to Bub's thought. It is further argued that there is implicit in the quantum information-theoretic tradition a set of ideas that mark a genuinely new alternative to the framework of quantum logic. These ideas are of considerable interest for the philosophy of quantum mechanics, a claim which I defend with an extended discussion of their application to our understanding of the philosophical significance of the no hidden variable theorem of Kochen and Specker.Comment: Presented to the 2007 conference, New Directions in the Foundations of Physic

Monetary policy, determinacy, and learnability in the open economy

We study how determinacy and learnability of global rational expectations equilibrium may be affected by monetary policy in a simple, two country, New Keynesian framework. The two blocks may be viewed as the U.S. and Europe, or as regions within the euro zone. We seek to understand how monetary policy choices may interact across borders to help or hinder the creation of a unique rational expectations equilibrium worldwide which can be learned by market participants. We study cases in which optimal policies are being pursued country by country as well as some forms of cooperation. We find that open economy considerations may alter conditions for determinacy and learnability relative to closed economy analyses, and that new concerns can arise in the analysis of classic topics such as the desirability of exchange rate targeting and monetary policy cooperation. JEL Classification: E52, F33indeterminacy, international policy coordination, monetary policy rules, new open economy macroeconomics

The learnability criterion and monetary policy

Expectations of the future play a large role in macroeconomics. The rational expectations assumption, which is commonly used in the literature, provides an important benchmark, but may be too strong for some applications. This paper reviews some recent research that has emphasized methods for analyzing models of learning, in which expectations are not initially rational but which may become rational eventually provided certain conditions are met. Many of the applications are in the context of popular models of monetary policy. The goal of the paper is to provide a largely nontechnical survey of some, but not all, of this work and to point out connections to some related research.Monetary policy ; Rational expectations (Economic theory)

Real-Time Time-Varying Equilibrium Interest Rates: Evidence on the Czech Republic

This paper examines (real-time) equilibrium interest rates in the Czech Republic in 2001:1- 2005:12 estimating various specifications of simple Taylor-type monetary policy rules. First, we estimate it using GMM. Second, we apply structural time-varying coefficient model with endogenous regressors to evaluate fluctuations of equilibrium interest rate over time. The results suggest that there is substantial interest rate smoothing and central bank primarily responds to inflation (forecast) developments. The estimated parameters seem to sustain the equilibrium determinacy. We find that the equilibrium interest rates gradually decreased over sample period to the levels comparable to those of in the euro area reflecting capital accumulation, smaller risk premium and successful disinflation in the Czech economy.http://deepblue.lib.umich.edu/bitstream/2027.42/57228/1/wp848 .pd

Monetary policy, determinacy, and learnability in a two-block world economy

We study how determinacy and learnability of worldwide rational expectations equilibrium may be affected by monetary policy in a simple, two country, New Keynesian framework under both fixed and flexible exchange rates. We find that open economy considerations may alter conditions for determinacy and learnability relative to closed economy analyses, and that new concerns can arise in the analysis of classic topics such as the desirability of exchange rate targeting and monetary policy cooperation.Monetary policy ; Foreign exchange

The prospects for mathematical logic in the twenty-first century

The four authors present their speculations about the future developments of mathematical logic in the twenty-first century. The areas of recursion theory, proof theory and logic for computer science, model theory, and set theory are discussed independently.Comment: Association for Symbolic Logi

The Role of "Determinacy" in Monetary Policy Analysis

It is well known that the concept of "determinacy"-a single stable solution-plays a major role in contemporary monetary policy analysis. But while determinacy is desirable, other things equal, it is not necessary for a solution to be plausible and is not sufficient for a solution to be desirable. There is a related but distinct criterion of "learnability" that seems more crucial. This paper argues that recognition of information feasibility requires that a candidate solution must, to be plausible, be quantitatively learnable on the basis of information generated by the economy itself. Since a prominent least- squares(LS) learning process is highly "biased" toward learnability, it is reasonable to regard it as a necessary condition for any specific solution to be relevant. This implies that determinacy is not necessary for policy analysis; there may be more than one stable solution but only one that is LS learnable. Also, determinacy is not sufficient for satisfactory policy analysis; explosive solutions pertaining to nominal variables will not be eliminated by transversality conditions. For these and other reasons, the role of determinacy in monetary policy analysis should be reconsidered and substantially de-emphasized.Determinacy, Learnability, Rational Expectations, Multiple Solutions, Monetary Policy