Research Database

Models with sticky prices predict that monetary policy changes will affect relative prices and relative quantities in the short run because some prices are more flexible than others. In U.S. micro data, the degree of price stickiness differs dramatically across consumption categories. This study exploits that diversity to ask whether popular measures of monetary shocks (for example, innovations in the federal funds rate) have the predicted effects. The study finds that they do not. Short-run responses of relative prices have the wrong sign. And monetary policy shocks seem to have persistent effects on both relative prices and relative quantities, rather than the transitory effects one would expect from differences in price flexibility across goods. The findings reject the joint hypothesis that the sticky-price models typically employed in policy analysis capture the U.S. economy and that commonly used monetary policy shocks represent exogenous shifts.

No, and maybe not.

This paper is a comment on P.C.B. Phillips, “To criticise the critics: an objective Bayesian analysis of stochastic trends” [Phillips (1990)]. Departing from the likelihood of an univariate autoregressive model different routes that lead to a posterior odds analysis of the unit root hypothesis are explored, where the differences in routes are due to the different choices of the prior. Improper priors like the uniform and the Jeffreys prior are less suited for Bayesian inference on a sharp null hypothesis as the unit root. A proper normal prior on the mean of the process is analyzed and empirical results using extended Nelson/Plosser data are presented.