We show that the prediction for the primordial tensor power spectrum cannot be modified at leading order in derivatives. Indeed, one can always set to unity the speed of propagation of gravitational waves during inflation by a suitable disformal transformation of the metric, while a conformal one can make the Planck mass time independent. Therefore, the tensor amplitude unambiguously fixes the ...

An optimising model of price adjustment with missing information is developed where firms choose the speed of price adjustment to minimise the expected loss in disequilibrium. The loss is due to lost profits and the expected cost of failing to coordinate price changes with competitors. Assuming that a higher speed of price adjustment decreases the former and increases the latter, it is shown th...

I develop an extension of the standard New Keynesian model to monetary policy regime switching to study the impact of uncertainty around the future inflation target. First, I fully characterize how the responses of current inflation and output to inflation target uncertainty depend on the monetary policy rule. If monetary policy is passive, inflation may increase far beyond the anticipated incr...

I develop an extension of the standard New Keynesian model to monetary policy regime switching to study the impact of uncertainty around the future inflation target. First, I fully characterize how the responses of current inflation and output to inflation target uncertainty depend on the monetary policy rule. If monetary policy is passive, inflation may increase far beyond the anticipated incr...

In this paper we approach the inflation expectations and the real interest rate by using the information contained in the yield curve. We decompose nominal interest rates into real risk-free rates, inflation expectations and risk premia using an affine model that takes as factors the observed inflation rate and the parameters generated in the zero yield curve estimation. Under this approach we ...

the issue of this paper is the relationships between inflation rate , unemployment rate and production, one of the main discussions in macroeconomic models. this 'paper is an effort 'to determine the relationship between the above- mentioned phenomenon in the short-and in the long 11m as well as to calculate the natural rate of unemployed in iran. for this purpose, the theoretical mod...

This paper shows that plausible modifications to the Taylor rule for monetary policy can help explain several empirical anomalies to the behavior of inflation in the new-Keynesian general equilibrium model. The key anomalies considered are (1) the persistence of inflation, both in reduced form and after conditioning on inflation’s driving processes, (2) the positive correlation between the outp...