宏观经济管理学与财务知识分析规范

5-1,5-2,5,AggregateSupplyandDemand,ItemItemItemEtc.,5-3,Introduction,ThelastfewchaptershavedetailedmodelsoflongruneconomicgrowthnowturntoshortrunfluctuationsintheeconomythatconstitutethebusinesscycleTheAS/ADmodelisthebasicmacroeconomictoolforstudyingoutputfluctuationsandthedeterminationofthepricelevelandtheinflationrateCanbeusedtoexplainhowtheeconomydeviatesfromapathofsmoothgrowthovertime,andtoexploretheconsequencesofgovernmentpoliciesintendedtoreduceunemploymentandoutputfluctuations,andmaintainstableprices,5-4,ASandAD,Aggregatesupplycurvedescribes,foreachgivenpricelevel,thequantityofoutputfirmsarewillingtosupplyUpwardslopingsincefirmsarewillingtosupplymoreoutputathigherpricesAggregatedemandcurveshowsthecombinationsofthepricelevelandthelevelofoutputatwhichthegoodsandmoneymarketsaresimultaneouslyinequilibriumDownwardslopingsincehigherpricesreducethevalueofthemoneysupply,whichreducesthedemandforoutputIntersectionofASandADcurvesdeterminestheequilibriumlevelofoutputandpricelevel,5-5,AS,AD,andEquilibrium,ASandADintersectatpointEinFigure5-1Equilibrium:AS=ADEquilibriumoutputisY0ObservedlevelofoutputintheeconomyatparticularpointintimeEquilibriumpricelevelisP0Observedpricelevelintheeconomyatparticularpointintime,InsertFigure5-1here,5-6,AS,AD,andEquilibrium,ShiftsineithertheASorADscheduleresultsinachangeintheequilibriumlevelofpricesandoutputIncreaseinADincreaseinPandYDecreaseinADdecreaseinPandYIncreaseinASdecreaseinPandincreaseinYDecreaseinASincreaseinPanddecreaseinY,InsertFigure5-2here,Figure5-2illustratesanincreaseinADresultingfromanincreaseinmoneysupply.,5-7,AS,AD,andEquilibrium,Theamountoftheincrease/decreaseinPandYafterashiftineitheraggregatesupplyoraggregatedemanddependson:TheslopeoftheAScurveTheslopeoftheADcurveTheextentoftheshiftofAS/AD,InsertFigure5-3here,Figure5-3showstheresultofanadverseASshock:ASY,P,5-8,ClassicalSupplyCurve,Theclassicalsupplycurveisvertical,indicatingthatthesameamountofgoodswillbesupplied,regardlessofpriceFigure5-4(b)BasedupontheassumptionthatthelabormarketisinequilibriumwithfullemploymentofthelaborforceThelevelofoutputcorrespondingtofullemploymentofthelaborforce=potentialGDP,Y*,InsertFigure5-4here,LongrunversionoftheAScurve,5-9,ClassicalSupplyCurve,Y*growsovertimeastheeconomyaccumulatesresourcesandtechnologyimprovesAScurvemovestotherightThegrowththeorymodelsdescribedinearlierchaptersexplainthelevelofY*inaparticularperiodY*is“exogenouswithrespecttothepricelevel”illustratedasaverticallinesincegraphedintermsofthepricelevel,InsertFigure5-5here,5-10,KeynesianSupplyCurve,TheKeynesiansupplycurveishorizontal,indicatingfirmswillsupplywhateveramountofgoodsisdemandedattheexistingpricelevelFigure5-4(a)Sinceunemploymentexists,firmscanobtainanyamountoflaboratthegoingwagerateSinceaveragecostofproductiondoesnotchangeasoutputchanges,firmswillingtosupplyasmuchasisdemandedattheexistingpricelevel,InsertFigure5-4here,again,5-11,KeynesianSupplyCurve,IntellectualgenesisoftheKeynesianAScurveisfoundintheGreatDepression,whenitseemedfirmscouldincreaseproductionwithoutincreasingPbyputtingidleKandNtoworkAdditionally,pricesareviewedas“sticky”intheshortrun,orfirmsarereluctanttochangepricesandwageswhendemandshiftsInsteadfirmsincrease/decreaseoutputinresponsetodemandshift=flatAScurveintheshortrun,ShortrunversionoftheAScurve,5-12,FrictionalUnemploymentandtheNaturalRateofUnemployment,Takenliterally,theclassicalmodelimpliesthatthereisnoinvoluntaryunemploymenteveryonewhowantstoworkisemployedInrealitythereissomeunemploymentduetofrictionsinthelabormarket(Ex.Someoneisalwaysmovingandlookingforanewjob)TheunemploymentrateassociatedwiththefullemploymentlevelofoutputisthenaturalrateofunemploymentNaturalrateofunemploymentistherateofunemploymentarisingfromnormallabormarketfrictionsthatexistwhenthelabormarketisinequilibrium,5-13,ASandthePriceAdjustmentMechanism,AScurvedescribesthepriceadjustmentmechanismwithintheeconomyFigure5-6showstheSRAScurveinblackandtheLRASingreen,andtheadjustmentfromtheSRtotheLRTheAScurveisdefinedbytheequation:(1)wherePt-1isthepricelevelnextperiodPtisthepriceleveltodayY*ispotentialoutput,InsertFigure5-6here,5-14,ASandthePriceAdjustmentMechanism,(1)Ifoutputisabovepotential(YY*),priceswillincreaseandbehighernextperiodIfoutputisbelowpotential(YY*,pricewillbehigher(ASshiftingup)byt=1ProcesscontinuesuntilY=Y*,InsertFigure5-6here,5-16,ASandthePriceAdjustmentMechanism,(1)ThespeedofthepriceadjustmentmechanismiscontrolledbytheparameterIfislarge,ASmovesquickly(thecounterclock-wiserotationsinFigure5-6(a)Ifissmall,pricesadjustslowlyisofimportancetopolicymakers:Ifislarge,theASmechanismwillreturntheeconomytoY*relativelyquicklyIfissmall,mightwanttouseADpolicytospeeduptheadjustmentprocess,InsertFigure5-6here,5-17,ADCurveandShiftsinAD,ADshowsthecombinationofthepricelevelandlevelofoutputatwhichthegoodsandmoneymarketsaresimultaneouslyinequilibriumShiftsinADdueto:PolicymeasuresChangesinG,T,andMSConsumerandinvestorconfidence,InsertFigure5-8here,Figure5-8showsanoutwardshiftinADresultingfromanincreaseinthemoneysupply.,5-18,ADRelationshipBetweenOutputandPrices,KeytotheADrelationshipbetweenoutputandpricesisthedependencyofADonrealmoneysupplyRealmoneysupply=valueofmoneyprovidedbythecentralbankandthebankingsystemRealmoneysupplyiswrittenas,whereisthenominalmoneysupply,andPisthepricelevelANDForagivenlevelof,highpricesresultinlowORhighpricesmeanthatthevalueofthenumberofavailabledollarsislowandthusahighP=lowlevelofAD,InverserelationshipbetweenPandYdownwardslopingADcurve,5-19,ADandtheMoneyMarket,Forthemoment,ignorethegoodsmarketandfocusonthemoneymarketandthedeterminationofADThequantitytheoryofmoneyoffersasimpleexplanationofthelinkbetweenthemoneymarketandADThetotalnumberofdollarsspentinayear,NGDP,isP*YThetotalnumberoftimestheaveragedollarchangeshandsinayearisthevelocityofmoney,VThecentralbankprovidesMdollarsThefundamentalequationunderlyingthequantitytheoryofmoneyisthequantityequation:(2),5-20,ADandtheMoneyMarket,(2)Ifthevelocityofmoneyisassumedconstant,equation(2)becomes,andisanequationfortheADcurveForagivenlevelofM,anincreaseinYmustbeoffsetbyadecreaseinP,andviceversaInverserelationshipbetweenYandPasillustratedbydownwardslopingADcurveAnincreaseinMshiftstheADcurveupwardforanyvalueofYIllustratedinFigure5-8,5-21,ChangesintheMoneyStockandAD,AnincreaseinthenominalmoneystockshiftstheADscheduleupexactlyinproportiontotheincreaseinnominalmoneySupposecorrespondstoADandtheeconomyisoperatingatP0andY0Ifmoneystockincreasesby10%to,ADshiftstoADthevalueofPcorrespondingtoY0mustbeP=1.1P0ThereforerealmoneybalancesandYareunchanged,InsertFigure5-8here,again,5-22,ADpolicyandtheKeynesianSupplyCurve,Figure5-9showstheADscheduleandtheKeynesiansupplyscheduleInitialequilibriumisatpointE(AS=AD)SupposeanaggregatedemandpolicyincreasesADtoADThenewequilibriumpoint,E,correspondstothesamepricelevel,andahigherlevelofoutput(employmentisalsolikelytoincrease),InsertFigure5-9here,5-23,ADpolicyandtheClassicalSupplyCurve,Intheclassicalcase,ASscheduleisverticalatFElevelofoutputUnliketheKeynesiancase,thepricelevelisnotgiven,butdependsupontheinteractionbetweenASandADSupposeADincreasestoAD:Attheoriginalpricelevel,spendingwouldincreasetoEBUTfirmscannotobtaintheNrequiredtomeettheincreaseddemandAsfirmshiremoreworkers,wagesandcostsofproductionincrease,andfirmsmustchargehigherpriceMoveupASandADcurvestoEwhereAS=AD,InsertFigure5-10here,RESULT:IncreaseinADresultsinhigherprices,butnotoutput,5-24,ADpolicyandtheClassicalSupplyCurve,TheincreaseinpricefromtheincreaseinADreducestherealmoneystock,andleadstoareductioninspendingTheeconomyonlymovesupADuntilpriceshaverisenenough,andM/Phasfallenenough,toreducetotalspendingtoalevelconsistentwithfullemploymentthisistrueatE,whereAD=AS,InsertFigure5-10here,5-25,SupplySideEconomics,SupplysideeconomicsfocusesonASasthedriverintheeconomySupplysidepoliciesarethosethatencouragegrowthinpotentialoutputshiftAStorightSuchpolicymeasuresinclude:RemovingunnecessaryregulationMaintainingefficientlegalsystemEncouragingtechnologicalprogressPoliticiansusethetermsupplysideeconomicsinreferencetotheideathatcuttingtaxeswillincreaseASenoughthattaxcollectionswillactuallyincrease,ratherthanfall,5-26,SupplySideEconomics,CuttingtaxrateshasanimpactonbothASandADADshiftstoADduetoincreaseindisposableincomeShiftisrelativelylargecomparedtothatoftheASASshiftstoASastheincentivetoworkincreasesInshortrun,economymovesfromEtoE:GDPincreases,taxrevenuesfallproportionatelylessthantaxcut(ADeffect)IntheLR,economymovestoEasAScurveshif