【PPT精品课件】货币金融学7版英文课件--ch28-大学课.pptx

Chapter 28Rational Expectations:Implications for Policy 2005 Pearson Education Canada Inc.Lucas CritiqueLucas challenges usefulness of econometric models for policy evaluation1.Critique follows from RE implication that change in way variable moves,changes way expectations are formed2.Policy change,changes relationship between expectations and past behavior3.Estimated relationships in econometric model change4.Therefore,cant be used to evaluate change in policyExample:Evaluate effect on long rate from Bank policy raising short-term i permanently,if in past changes in i quickly reversed1.Estimated term structure relationship indicates only small change in long rate2.Once realize short i permanently,average future short rates a lot,long rate a lot3.Another implication of Lucas analysis:expectations about policy influences response to policy2 2005 Pearson Education Canada Inc.New Classical ModelAssumptions:1.Rational expectations2.Wages and prices completely flexible,adjust fully to changes in expected price levelImplications:1.Policy ineffectiveness proposition:anticipated policy has no effect on business cycle2.Effects of policy are uncertain because depend on expectations3.No beneficial effect from activist policy:supports nonactivism 2005 Pearson Education Canada Inc.3Response to Unanticipated Policy in New Classical Model1.M,AD shifts right to AD22.Because M unanticipated,expected price level unchanged and AS stays at AS13.Go to 2:Y,P 4 2005 Pearson Education Canada Inc.Response to Anticipated Policy in New Classical Model1.M,AD shifts right to AD22.M anticipated,expected price level to P2,AS shifts in to AS23.Go to 2:Y unchanged,P by more5 2005 Pearson Education Canada Inc.New Keynesian ModelAssumptions:1.Rational expectations2.Wages and prices have rigidity:dont adjust fully to changes in expected price levelImplications:1.Unanticipated policy has larger effect on Y than anticipated policy2.Policy ineffectiveness does not hold:Anticipated policy does affect Y3.Does not rule out beneficial effect from activist policy4.However,effects of policy are affected by expectations:designing policy is tough 2005 Pearson Education Canada Inc.6Response to Expansionary Policy in New Keynesian Model1.M,AD shifts out to AD22.Panel(a):M unanticipated,AS stays at AS1;go to U,Y P 3.Panel(b):M anticipated,AS shifts to ASA(not all the way to AS2);go to A,Y by less than in panel(a),P by more7 2005 Pearson Education Canada Inc.Summary:The Three Models 2005 Pearson Education Canada Inc.8Response to Expansionary Policy in the Three Models9 2005 Pearson Education Canada Inc.Analysis of Figure 28-5:Response to Expansionary Policy in the Three ModelsM,AD shifts out to AD2Traditional Model(a)1.AS stays at AS1 whether M anticipated or not;go to 1,Y P New Classical Model(b)1.M unanticipated,AS stays at AS1;go to 1,Y,P 2.M anticipated,AS to AS2;go to 2,Y unchanged,P by moreNew Keynesian Model(c)1.M unanticipated,AS stays at AS1;go to 1,Y P 2.M anticipated,AS to AS2;go to 2,Y by less,P by more10 2005 Pearson Education Canada Inc.Anti-Inflation Policy in the Three Models 2005 Pearson Education Canada Inc.11Analysis of Figure 28-6:Anti-Inflation Policy in the Three Models1.Ongoing,so moving from AD1 to AD2,AS1 to AS2,point 1 to 22.Anti-policy,AD kept at AD1Traditional Model(a)1.AS to AS2 whether policy anticipated or not;go to 2,Y,New Classical Model(b)1.Unanticipated:AS to AS2;go to 2,Y,2.Anticipated:AS stays at AS1;stay at 1,Y unchanged,to zeroNew Keynesian Model(c)1.Unanticipated:AS to AS2;go to 2,Y,2.Anticipated:AS to AS2;go to 2,Y by less,by more12 2005 Pearson Education Canada Inc.Credibility and the Reagan DeficitsReagan deficits may have made 198182 recession worse after Fed anti-policyAnalysis with Figure 28-61.Anti-policy kept AD at AD12.Feds anti-policy less credible,so AS kept rising to AS23.Go to 2 in panels(b)and(c);Y by more than if anti-policy credibleImpact of Rational Expectations Revolution1.More aware of importance of expectations and credibility2.Lucas critique has caused most economists to doubt use of conventional econometric models for policy evaluation3.Since effect of policy depends on expectations,economists less activist4.Policy effectiveness proposition not widely accepted,most economists take intermediate position that activist policy could be beneficial but is tough to design13