Credibility and Time Inconsistency in a Stochastic World
This paper re-examines the issue of the credibility and sustainability of optimal policies derived from Pontryagin's Maximum Principle and generally regarded as time-inconsistent, in models with forward-looking rational expectations. Specifically, it considers the behaviour of such models in the presence of continuing stochastic noise. This is shown to convert the policy problem from a one-shot dynamic policy game to a continuing game, giving governments an incentive to invest in a reputation for not reneging on the full optimal rule. This incentive may, in certain circumstances, render the full optimal rule credible and therefore sustainable. It is demonstrated that a sufficiently low degree of discounting on the part of government, or a sufficiently high variance of shocks (measured relative to the initial displacement) ensures the sustainability of the full optimal rule. Using a simple dynamic open economy model, these conditions are shown to be plausible unless the discount rate is very high.
|Date of creation:||Feb 1986|
|Date of revision:|
|Contact details of provider:|| Postal: Centre for Economic Policy Research, 77 Bastwick Street, London EC1V 3PZ.|
Phone: 44 - 20 - 7183 8801
Fax: 44 - 20 - 7183 8820
|Order Information:|| Email: |
When requesting a correction, please mention this item's handle: RePEc:cpr:ceprdp:94. See general information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: ()
If references are entirely missing, you can add them using this form.