【PPT精品课件】货币金融学7版英文课件--ch28-大学课

Chapter28RationalExpectations:ImplicationsforPolicy©2005PearsonEducationCanadaInc.©2005PearsonEducationCanadaInc.28-2LucasCritiqueLucaschallengesusefulnessofeconometricmodelsforpolicyevaluation1.CritiquefollowsfromREimplicationthatchangeinwayvariablemoves,changeswayexpectationsareformed2.Policychange,changesrelationshipbetweenexpectationsandpastbehavior3.Estimatedrelationshipsineconometricmodelchange4.Therefore,can’tbeusedtoevaluatechangeinpolicyExample:EvaluateeffectonlongratefromBankpolicyraisingshort-termipermanently,ifinpastchangesiniquicklyreversed1.Estimatedtermstructurerelationshipindicatesonlysmallchangeinlongrate2.Oncerealizeshortipermanently,averagefutureshortratesalot,longratealot3.AnotherimplicationofLucasanalysis:expectationsaboutpolicyinfluencesresponsetopolicy28-3NewClassicalModelAssumptions:1.Rationalexpectations2.Wagesandpricescompletelyflexible,adjustfullytochangesinexpectedpricelevelImplications:1.Policyineffectivenessproposition:anticipatedpolicyhasnoeffectonbusinesscycle2.Effectsofpolicyareuncertainbecausedependonexpectations3.Nobeneficialeffectfromactivistpolicy:supportsnonactivism©2005PearsonEducationCanadaInc.©2005PearsonEducationCanadaInc.28-4ResponsetoUnanticipatedPolicyinNewClassicalModel1.M,ADshiftsrighttoAD22.BecauseMunanticipated,expectedpricelevelunchangedandASstaysatAS13.Goto2':Y,P©2005PearsonEducationCanadaInc.28-5ResponsetoAnticipatedPolicyinNewClassicalModel1.M,ADshiftsrighttoAD22.Manticipated,expectedpriceleveltoP2,ASshiftsintoAS23.Goto2:Yunchanged,Pbymore28-6NewKeynesianModelAssumptions:1.Rationalexpectations2.Wagesandpriceshaverigidity:don’tadjustfullytochangesinexpectedpricelevelImplications:1.UnanticipatedpolicyhaslargereffectonYthananticipatedpolicy2.Policyineffectivenessdoesnothold:AnticipatedpolicydoesaffectY3.Doesnotruleoutbeneficialeffectfromactivistpolicy4.However,effectsofpolicyareaffectedbyexpectations:designingpolicyistough©2005PearsonEducationCanadaInc.©2005PearsonEducationCanadaInc.28-7ResponsetoExpansionaryPolicyinNewKeynesianModel1.M,ADshiftsouttoAD22.Panel(a):Munanticipated,ASstaysatAS1;;gotoU,YP3.Panel(b):Manticipated,ASshiftstoASA(notallthewaytoAS2);gotoA,Ybylessthaninpanel(a),Pbymore28-8Summary:TheThreeModels©2005PearsonEducationCanadaInc.©2005PearsonEducationCanadaInc.28-9ResponsetoExpansionaryPolicyintheThreeModels©2005PearsonEducationCanadaInc.28-10AnalysisofFigure28-5:ResponsetoExpansionaryPolicyintheThreeModelsM,ADshiftsouttoAD2TraditionalModel(a)1.ASstaysatAS1whetherManticipatedornot;goto1',YPNewClassicalModel(b)1.Munanticipated,ASstaysatAS1;goto1',Y,P2.Manticipated,AStoAS2;goto2,Yunchanged,PbymoreNewKeynesianModel(c)1.Munanticipated,ASstaysatAS1;goto1',YP2.Manticipated,AStoAS2;goto2',Ybyless,Pbymore28-11Anti-InflationPolicyintheThreeModels©2005PearsonEducationCanadaInc.©2005PearsonEducationCanadaInc.28-12AnalysisofFigure28-6:Anti-InflationPolicyintheThreeModels1.Ongoing,somovingfromAD1toAD2,AS1toAS2,point1to22.Anti-policy,ADkeptatAD1TraditionalModel(a)1.AStoAS2whetherpolicyanticipatedornot;goto2',Y,NewClassicalModel(b)1.Unanticipated:AStoAS2;goto2',Y,2.Anticipated:ASstaysatAS1;stayat1,Yunchanged,tozeroNewKeynesianModel(c)1.Unanticipated:AStoAS2;goto2',Y,2.Anticipated:AStoAS2'';goto2'',Ybyless,bymore28-13CredibilityandtheReaganDeficitsReagandeficitsmayhavemade1981–82recessionworseafterFedanti-policyAnalysiswithFigure28-61.Anti-policykeptADatAD12.Fed’santi-policylesscredible,soASkeptrisingtoAS23.Goto2'inpanels(b)and(c);Ybymorethanifanti-policycredibleImpactofRationalExpectationsRevolution1.Moreawareofimportanceofexpectationsandcredibility2.Lucascritiquehascausedmosteconomiststodoubtuseofconventionaleconometricmodelsforpolicyevaluation3.Sinceeffectofpolicydependsonexpectations,economistslessactivist4.Policyeffectivenesspropositionnotwidelyaccepted,mosteconomiststakeintermediatepositionthatactivistpolicycouldbebeneficialbutistoughtodesign