摘要：We examine the effects of the release by a central bank of its expected future
interest rate in a simple two-period model with heterogeneous information
between the central bank and the private sector. The model is designed to rule
out common-knowledge and time-inconsistency effects. Transparency - when the
central bank publishes its interest rate path - fully aligns central bank and
private-sector expectations about the future inflation rate. The private sector
fully trusts the central bank to eliminate future inflation and sets the
long-term interest rate accordingly, leaving only the unavoidable central bank
forecast error as a source of inflation volatility. Under opacity - when the
central bank does not publish its interest rate forecast - current-period
inflation differs from its target not just because of the unavoidable central
bank expectation error but also because central bank and privatesector
expectations about future inflation and interest rates are no longer aligned.
Opacity may be creative and raise welfare if the private sector's interpretation
of the current interest rate leads it to form a view of expected inflation and
to set the long-term rate in a way that systematically offsets the effect of the
central bank forecast error on inflation volatility. Conditions that favor the
case for transparency are a high degree of precision of central bank information
relative to private-sector information, a high precision of early information,
and a high elasticity of current to expected inflation.
