货币金融学（第十三版）课件 英文第24章 货币政策中预期的作用

TheEconomicsofMoney,Banking,andFinancialMarketsThirteenthEditionChapter24TheRoleofExpectationsinMonetaryPolicyCopyright©2022,2019,2016PearsonEducation,Inc.AllRightsReservedPreviewThischapterexaminestheanalysisbehindtherationalexpectationsrevolution.LearningObjectives24.1SummarizetheLucascritique.24.2Compareandcontrasttheuseofpolicyrulesversusdiscretionarypolicy.24.3Summarizeandillustratethebenefitsofacrediblecentralbank.24.4Identifythewaysinwhichcentralbankscanestablishandmaintaintheircredibility.LucasCritiqueofPolicyEvaluationMacro-econometricmodels:Collectionsofequationsthatdescribestatisticalrelationshipsamongeconomicvariables.Theyareusedbyeconomiststoforecasteconomicactivityandtoevaluatethepotentialeffectsofpolicyoptions.Inhisfamouspaper“EconometricPolicyEvaluation:ACritique,”RobertLucasarguedthateconometricmodelsareunreliableforevaluationpolicyoptionsiftheydonotincorporaterationalexpectations.AccordingtoLucas,whenpolicieschange,publicexpectationswillshiftaswell,andsuchchangingexpectations(asignoredbyconventionaleconometricmodels)canhavearealeffectoneconomicbehaviorandoutcomes.Application:TheTermStructureofInterestRatesThetermstructureapplicationdemonstratesanaspectoftheLucascritique:Theeffectsofaparticularpolicydependcriticallyonthepublic’sexpectationsaboutthepolicy.Ifthepublicexpectstheriseintheshort-terminterestratetobemerelytemporary,theresponseoflong-terminterestrateswillbenegligible.Ifthepublicexpectstherisetobemorepermanent,theresponseoflong-termrateswillbefargreater.TheLucascritiquepointsoutnotonlythatconventionaleconometricmodelscannotbeusedforpolicyevaluationbutalsothatthepublic’sexpectationsaboutapolicywillinfluencetheresponsetothatpolicy.PolicyConduct:RulesorDiscretion?(1of2)Policyrulesarebindingplansthatspecifyhowpolicywillrespond(ornotrespond)toaparticulardatasuchasunemploymentandinflation.Policydiscretionisappliedwhenpolicymakersmakenocommitmenttofutureactions,butinsteadmakewhattheybelieveinthatmomenttobetherightdecisionforthesituation.FinnKydland,EdwardPrescott,andGuillermoCalvoarguedthatdiscretionarypolicyissubjecttothetime-inconsistencyproblem—thetendencytodeviatefromgoodlong-runplanswhenmakingshort-rundecisions.PolicyConduct:RulesorDiscretion?(2of2)Policymakersarealwaystemptedtopursueexpansionarypolicytoboostoutputintheshortrun,butthebestpolicyisnottopursueit:Unexpectedexpansionarypolicywillraiseworkers,andfirms’expectationsaboutinflation,thusdrivingupwagesandprices,andtheendresultswillbehigherinflationbutnoincreaseinoutput.Thetime-inconsistencyproblemimpliesthatapolicywillhavebetterinflationperformanceinthelongrunifitdoesnottrytosurprisepeoplewithanunexpectedlyexpansionarypolicy,butinsteadstickstoacertainrule.TypesofRulesNonactivistrules,whichdonotreacttoeconomicactivity,includeMiltonFriedman’sconstant-money-growth-raterule,inwhichthemoneysupplyiskeptgrowingataconstantrateregardlessofthestateoftheeconomy.VariantsoftheFriedmansrule,asproposedbyothermonetaristssuchasBennettMcCallumandAlanMeltzer,allowtherateofmoneysupplygrowthtobeadjustedforshiftsinvelocity.Activistrules,whichspecifythatmonetarypolicyreactstochangesineconomicactivity,suchasthelevelofoutputandtoinflation.TheCaseforRulesOneargumentforrulesisthattheyleadtodesirablelong-runoutcomesbecausecommitmenttoapolicyrulesolvesthetime-inconsistencyproblembecauseitdoesnotallowpolicymakerstoexercisediscretionandtrytoexploittheshort-runtradeoffbetweeninflationandemployment.Anotherargumentforrulesisthatpolicymakersandpoliticianscannotbetrusted:Politicianshavestrongincentivestopurseexpansionarypolicythathelpthemwinthenextelection,leadingtothepoliticalbusinesscycle.ThePoliticalBusinessCycleandRichardNixonThereissomeargumentthatpriortothe1972PresidentialelectiontheNixonadministrationtookstepstoensurealandslidevictory—thelargestinU.S.historytothatpointintime.Amongotherthings,itimposedwageandpricecontrolsontheeconomy,whichtemporarilyloweredtheinflationrate.Aftertheelection,thosesameactionscontributedtoasurgeininflation.Nixonalsopursuedexpansionaryfiscalpolicybycuttingtaxes.AndithasbeenrumoredthatthechairoftheFederalReserveatthetime,ArthurBurns,succumbedtodirectpressurefromNixontomaintainlowinterestratesthroughelectionday.TheCaseforDiscretionDrawbacksofpolicyrules:RulescanbetoorigidbecausetheycannotforeseeeverycontingencyRulesdonoteasilyincorporatetheuseofjudgmentbecausemonetarypolicymakersneedtolookatawiderangeofinformationandsomeofthisinformationisnoteasilyquantifiableNoonereallyknowswhatthetruemodeloftheeconomyisandsoanypolicyrulethatisbasedonaparticularmodelwillprovetobewrongifthemodelisnotcorrectEvenifthemodelwerecorrect,structuralchangesintheeconomywouldleadtochangesinthecoefficientsofthemodel(theLucascritique)TheDemiseofMonetaryTargetinginSwitzerlandIn19

75,forexample,theSwissNationalBank(Switzerland’scentralbank)adoptedmonetarytargetinginwhichitannouncedagrowthratetargetforthemonetaryaggregateM1.In1980,theSwissswitchedtheirgrowthratetargettoanevennarrowermonetaryaggregate,themonetarybase.However,problemswithmonetarytargetingledtheSwisstoabandonitinthe1990sandadoptamuchmoreflexibleframeworkfortheconductofmonetarypolicy.ConstrainedDiscretionConstraineddiscretion,developedbyBenBernankeandFredericMishkin,imposesaconceptualstructureandinherentdisciplineonpolicymakers,butwithouteliminatingallflexibility.Theideaistocombinesomeoftheadvantagesascribedtoruleswiththoseascribedtodiscretion.TheRoleofCredibilityandaNominalAnchorAnimportantwaytoconstraindiscretionisbycommittingtoanominalanchor—a

nominalvariablethattiesdownthepricelevelorinflationtoachievepricestability.Ifthecommitmenttoanominalanchorhascredibility—itisbelievedbythepublic—itwillhavethefollowingbenefits:Thenominalanchorcanhelpovercomethetime-inconsistencyproblembyprovidinganexpectedconstraintondiscretionarypolicy.Thenominalanchorwillhelptoanchorinflationexpectations,leadingtosmallerfluctuationsininflationandinaggregateoutput.CredibilityandAggregateDemandShocks(1of2)Positiveaggregatedemandshocks(theA

DcurveshiftstotherightsothatinflationrisesaboveIfthecommitmenttothenominalanchoriscredible,thenexpectedinflationwillremainunchangedsothattheshort-runA

Scurve(asrepresentedbytheaboveequation)willnotshift.Theappropriatepolicyresponseistotightenmonetarypolicysothattheshort-runA

DcurveshiftsbackwhileinflationfallsbackdowntotheinflationtargetofCredibilityandAggregateDemandShocks(2of2)Positiveaggregatedemandshocks(theA

DcurveshiftstotherightsothatinflationrisesaboveIfmonetarypolicyisnotcredible,thepublicwouldworrythatthecentralbankwoulddrivetheA

Dcurvebackdownquickly,thenexpectedinflationπewillriseandsotheshort-runA

Scurvewillshiftuptotheleft,drivingupinflation.EvenifthecentralbanktightensmonetarypolicybyshiftingtheA

Dcurveback,inflationwouldhaverisenmorethanitwouldhaveifthecentralbankhadcredibility.Monetarypolicycredibilityhasthebenefitofstabilizinginflationintheshortrunwhenfacedwithpositivedemandshocks.Figure1CredibilityandAggregateDemandShocksCredibilityandAggregateSupplyShocks(1of2)Negativeaggregatedemandshocks(theA

DcurveshiftstotheleftsothataggregateoutputfallsbelowIfthecentralbank’scredibilityisweak,thepublicwillseeaneasingofmonetarypolicyasthecentralbank’slosingitscommitmenttothenominalanchorandsoitwillpursueinflationarypolicyinthefuture.Theresultisrisinginflationexpectations,sothattheshort-runA

Scurvewillshiftuptotheleft,sothataggregateoutputfallsevenfurther.Monetarypolicycredibilityhasthebenefitofstabilizingeconomicactivityintheshortrunwhenfacedwithnegativedemandshocks.CredibilityandAggregateSupplyShocks(2of2)Negativeaggregatesupplyshocks(theshort-runA

Scurveshiftstotheleft).Ifthecredibilityofthenominalanchoriscredible,inflationexpectationswillnotrise,sotheshort-runA

Scurvewillnotshiftfurther.Ifthecredibilityofthenominalanchorisweak,theninflationexpectationswillrise,sotheshort-runA

S

curvewillshiftfurtherupandtotheleft,causingevenhigherinflationandloweroutput.Monetarypolicycredibilityhasthebenefitofproducingbetteroutcomesonbothinflationandoutputintheshortrunwhenfacedwithnegativesupplyshocks.Figure2CredibilityandAggregateSupplyShocksApplication:ATaleofThreeOilPriceShocksAsindicatedbyFigure3,in1973,1979,and2007,theU.S.economywashitbythreemajornegativesupplyshockswhenthepriceofoilrosesharply;andyetinthefirsttwoepisodesinflationrosesharply,whileinthemostrecentepisodeitrosemuchless.Figure3InflationandUnemployment,1970–2020Source:

FederalReserveBankofSt.Louis,F

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E

Ddatabase:https:///series/UNRATE

;https:///series/CPIAUCSL

.CredibilityandAnti-InflationPolicyThegreaterthecredibilityofthecentralbankasaninflationfighter,themorerapidthedeclineininflationandthelowerthelossofoutputtoachievetheinflationobjective.Ifthecentralbankhasverylittlecredibility,thenthepublicwillnotbeconvincedthatthecentralbankwillstaythecoursetoreduceinflation,andtheywillnotrevisetheirinflationexpectations.Figure4CredibilityandAnti-InflationPolicyGlobal:EndingtheBolivianHyperinflation:ASuccessfulAnti-InflationProgramThemostremarkableanti-inflationprogramofrecenttimeswasimplementedinBolivia.Inthefirsthalfof1985,Bolivia’sinflationratewasrunningat20,000%andrising.Toreininmoneygrowthandestablishcredibility,thenewgovernmenttookdrasticactionsinAugust19

85toslashthebudgetdeficitbyshuttingdownmanystate-ownedenterprises,eliminatingsubsidies,freezingpublicsectorsalaries,andcollectinganewwealthtax.ApproachestoEstablishingCentralBankCredibilityInflationTargetingExchange-rateTargetingNominalG

D

PTargetingthecentralbankannouncesanobjectiveofhittingaparticularlevelofnominalG

D

PgrowthAppoint“Conservative”CentralBankersKennethRogoffofHarvardUniversitysuggestedthatanotherwaytoestablishpolicycredibilityisforthegovernmenttoappointcentralbankerswhohaveastrongaversiontoinflation.Thepublicwillthenexpectthatthe“conservative”centralbankerwillbelesstemptedtopursueexpansionarymonetarypolicya