The signaling effect of raising inflation

This paper argues that central bankers should raise inflation to signal their credibility to forward guidance policies. As inflation can be stabilized in normal times either because of central banker's credibility (e.g. because of reputation concerns) or because of his aversion to inflation, the private sector is unable to infer the central banker's type from observing stable inflation before a liquidity trap, jeopardizing the efficiency of forward guidance policy. We derive optimal policy in a new-Keynesian model subject to liquidity traps where agents are uncertain about the central banker's type and we show that the credible central banker can signal his type by raising inflation before a trap. We show that this signaling motive can justify level of inflation well above 2% but also that the low inflation volatility during the Great Moderation was insufficient to ensure fully efficient forward guidance when needed.