ofMacroeconomics(宏观经济学-加州大学-詹姆斯·布

Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-1,CHAPTER17,TheFutureofMacroeconomics,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-2,Questions,Whatmightthefutureofmacroeconomicsbring?Howmightthemacroeconomicstaughttwodecadesfromnowbedifferentfromthemacroeconomicstaughttoday?Whathavebeentheprincipalchangesinthewaymacroeconomicsistaughtoverthepasttwentyyears?,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-3,Questions,Whatadditionalchangestookplacetwentyyearsbeforethat-fromroughly1960toroughly1980?Whatdirectionwillmacroeconomicstakeiftherealbusinesscycleresearchprogramissuccessful?WhatdirectionwillmacroeconomicstakeifthenewKeynesianresearchprogramprovessuccessful?,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-4,Questions,Howwilleconomistsunderstandthefoundationsbehindthepowerofmonetarypolicy?,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-5,ThePastofMacroeconomics,A1936bookbyJohnMaynardKeynesshiftedeconomicresearchandmacroeconomicthoughtintonewanddifferentdirectionstheroleofexpectationsoffutureprofitsindetermininginvestmentthevolatilityofexpectationsofprofitsthepowerofthegovernmenttoaffecttheeconomythroughpolicythemultiplierprocess,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-6,ThePastofMacroeconomics,AfterWorldWarII,moremacroeconomictheorywasdevelopedtheIS-LMmodelwascreatedtherelationshipbetweeninterestratesandthemoneysupplywasinvestigatedthedifferencebetweenthebehaviorofthemacroeconomyintheflexible-pricelongrunandthefixed-priceshortrunwasclarified,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-7,ThePastofMacroeconomics,Butmacroeconomicstheoryin1960wasstillincompletenodiscussionoftherelationshipbetweenproductionandinflationnodetailedmodelofexpectationstheshortrunwasseenaslastingfordecadesfiscalpolicywasemphasized,whiletheroleofmonetarypolicywasdownplayedestimatesofthemultiplierweremuchhigherthanwebelievenowtobecorrect,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-8,ThePastofMacroeconomics,Between1960and1980,twopowerfulcritiquesoftheconventionalwisdomofmacroeconomicsoccurredthefirstwasbyMiltonFriedmanthestandardmodelsoverestimatedthegovernmentsabilitytocontroltheeconomythestandardmodelsoverestimatedthepoweroffiscalpolicyandunderestimatedthepowerofmonetarypolicythemoneysupplytellsusmostofwhatweneedtoknowabouthowpolicyisworkingthereisanaturalrateofunemployment,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-9,ThePastofMacroeconomics,thesecondwasbyRobertLucasKeynesianeconomicsfailstothinkthroughtheimportanceofexpectationssystematicchangesineconomicpolicywouldchangetheparametersoftheconsumptionandinvestmentfunctionsaswellasthelocationofthePhillipscurve,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-10,ThePastofMacroeconomics,Thelate1980sand1990swereatimeofideagenerationandexplorationmacroeconomistsexploredandtestedalargenumberofdifferentideasandmodelsthemainstreampolicy-analyticpositionofmacroeconomistsdidnotshiftmuch,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-11,TheFutureofMacroeconomics:RealBusinessCycles?,Keynesianandmonetaristeconomistsbelievethattherearetwokeyelementstounderstandingbusinesscyclesthedeterminantsofaggregatedemandthedivisionofchangesinnominalaggregatedemandintochangesinproductionandchangesinprices,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-12,TheFutureofMacroeconomics:RealBusinessCycles?,RealbusinesscycleeconomistsbelievethatchangesinnominalaggregatedemandaffectoutputandemploymentonlyslightlyandhavethemostimpactonpricesRealbusinesscycletheorybeginswiththeassumptionthatthesametheorythatdetermineswhathappensinthelongrunshouldbeappliedtofluctuationsintheshortrun,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-13,TheFutureofMacroeconomics:RealBusinessCycles?,Whilerealbusinesscycleeconomistsbelievethatpricescanberigid,theybelievethatthissluggishnessofpricesisnotveryrelevanttheyassumethatitisareasonablefirst-approximationtosupposethatthemoneysupplyandthelevelofpotentialoutputdeterminethepricelevelthelevelofpotentialoutputismore-or-lessequaltoactualrealGDP,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-14,TheFutureofMacroeconomics:RealBusinessCycles?,RealbusinesscycleeconomistsbelieveintheclassicaldichotomyrealvariableseffectivelydeterminethevaluesofrealquantitieslikerealGDPevenintheshortrunnominalvariablesdeterminethevaluesofnominalquantitieslikethepricelevel,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-15,TheFutureofMacroeconomics:RealBusinessCycles?,Realbusinesscycletheoryassumesthatthelevelofoutputwillvarywithshockstotheeconomyadversecostshocksleadtoarecessionasindividualsshouldspendlesstimeworkingbecauseitisnotprofitablefavorablecostshocksleadtoaboomperiodbecauseitisadvantageoustoproduceasmuchaspossible,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-16,ProblemsofRealBusinessCycleTheory,Unemploymentrealbusinesscycletheoryassumesthatthetotalhoursworkedatanymomentislargelydeterminedbyhowmanyhoursitmakessenseforpeopletoworkbutwhenworkhoursfall,itisnotbecausepeoplehavechosentoworkshortershiftsandavoidovertimeitisbecausetheyhavebecomeunemployed,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-17,ProblemsofRealBusinessCycleTheory,TechnologyandRealBusinessCyclesaccordingtorealbusinesscycletheory,productionfluctuatesbecauseofthechangingvalueofoutputandthechangingproductivityoftheeconomymoreisproducedwhentechnologyrisesrecessionsoccurwhencostincreasesmakeitinefficienttorunfactoriesatnearcapacitycriticsclaimthatcostincreaseslikethe1973oilpriceshockaretheexceptionratherthantherule,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-18,ProblemsofRealBusinessCycleTheory,MoneyandBusinessCyclesrealbusinesscycletheoriststendtoarguethatmonetarypolicyhaslittleimpactonproductionandemploymentfluctuationsinthemoneystockandrealinterestratesaremorereactionstochangesalreadytakingplacetheFederalReservebelievesthatitaffectsthelevelofinterestratesandthatitsdecisionscausechangesinproductionandemployment,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-19,TheFutureofMacroeconomics:NewKeynesianEconomics,Sincethe1930s,mainstreammacroeconomicshasattributedthesluggishnessofaggregatesupplytostickinessinwagesandpricesTherefore,fluctuationsinnominalaggregatedemandcausefluctuationsinoutputandemployment,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-20,TheFutureofMacroeconomics:NewKeynesianEconomics,Wheredoesthisstickinessandslowadjustmentofwagesandpricescomefrom?menucostsitiscostlyforbusinessestochangepricesstaggeredpricesandcoordinationfailuresafirmsbestchoiceforitspricemaydependonthepricesthatotherfirmsarechargingthismeansthatwagesandpricesmayexhibitinertia,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-21,DebtsandDeficits:RicardianEquivalence,Ifthegovernmentrunsabudgetdeficit,itwillmakeupthedeficitbyborrowingmoneynowandimplicitlycommittingtoraisetaxestorepaythedebtatsometimeinthefuture,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-22,DebtsandDeficits:RicardianEquivalence,EconomistRobertBarroarguesthatconsumerswillseethebudgetdeficitasanincreaseinfuturetaxesandcutbackonconsumptionwhatmattersforthedeterminationofconsumptionspendingthisyearisnotwhattaxesareleviedonyouthisyear,butwhatallthechangesingovernmentpolicytellyouaboutstreamoftaxesthisyearandinthefuture,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-23,DebtsandDeficits:RicardianEquivalence,ManyeconomistsbelievethatRicardianequivalencedoesnotholdforanumberofreasonsmyopialiquidityconstraintspeoplearedifferent,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-24,ConsumptionandSaving,Intheearly1900s,themarginalpropensitytoconsumewashighpeoplewereliquidityconstrainedThefinancialsysteminthepast50yearshasbecomemuchmoreflexibleeconomictheorywouldpredictthatthemarginalpropensitytoconsumewoulddeclineandthemultiplierprocesswouldbemoreorlessirrelevanttoaggregatedemand,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-25,ConsumptionandSaving,But,consumptionfallssignificantlywhentheeconomygoesintorecessionWhy?onepossibilityisthatconsumersarebothimpatientandriskaverseanotherpossibleexplanationisthatcurrentincomeisagoodproxyforpermanentincomeanothersuggestionisforeconomiststofocusonwhatpsychologistshavetosayabouthowhumansreason,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-26,DoesMonetaryPolicyHaveaLong-RunFuture?,EconomistshavetendedtoassumethatmonetarypolicyispowerfulandthatthereasonsforitspowerareuninterestingThefutureevolutionofthefinancialsystemmayunderminethesourcesofinfluencethatmonetarypolicytodaypossesses,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-27,DoesMonetaryPolicyHaveaLong-RunFuture?,Forecastingthefutureofmonetarypolicywillrequireadeeperknowledgeandbettermodelsofthesourcesofcentralbankpowerthanmacroeconomistscurrentlypossess,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-28,ChapterSummary,Modernmacroeconomicshasitsorigininthe“Keynesian”theoriesoftheGreatDepressionandpost-WWIIeraModernmacroeconomicswasreforgedbythemonetaristsunderMiltonFriedmaninthe1960sand1970s,andbytherationalexpectationseconomistsledbyRobertLucasinthe1970sand1980s,Copyright2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.,17-29,ChapterSummary,Perhapsthefocusonaggregatedemandwillturnoutinthelongruntohavebeenafalseroadperhapsabettertheoryo