国际经济学克鲁格曼第八版第十六章英文PPT课件.ppt

Chapter16OutputandtheExchangeRateintheShortRunThischapterbuildsontheshortrunandlongmodelsofexchangeratestoexplainhowoutputisrelatedtoexchangeratesintheshortrun Introduce DeterminantsofAggregateDemandinanOpenEconomyOutputMarketEquilibriumIntheShoutRun theDDScheduleAssetMarketEquilibriumIntheShoutRun theAAScheduleShoutRunEquilibriumForanEconomy DD AAScheduleTemporaryChangesinMonetaryandFiscalPolicy Introduce InflationBiasandOtherProblemsPermanentShiftsinMonetaryandFiscalPolicyMacroeconomicPolicyandtheCurrentAccountGradualTradeFlowAdjustmentandtheCurrentAccountDynamics TheJCurve 1 DeterminantsofAggregateDemandinanOpenEconomy AggregateDemand Inshortrun aggregatedemandistheaggregateamountofgoodsandservicesdemandedbyhouseholdsandfirmsthroughouttheworld country soverallshort runoutputleveldependsontheaggregatedemandforitsproductsD C I G CA inchapter12 C consumptionexpenditure I investmentexpenditure G governmentpurchases CA currentaccount netexportdemand EX IMIandGisgiven 1 1DeterminantsofConsumptionDemand consumeasdependingondisposableincome Yd thatis nationalincomelesstaxes Y T C C Yd consumptiondemandanddisposableincomearepositively disposableincome consumptiondemand consumptiondemandgenerallyrisesbylessbecausepartoftheincomeincreaseissaved 1 2DeterminantsofCurrentAccount CAisdeterminedbytwomainfactors realexchangerate q EP Pinchapter13 affectthecurrentaccountbyreflectingchangesinthepricesofdomesticgoodsandservicesrelativetoforeign q EP Pq realexchangerate isdomesticcurrencyrealexchangerateagainstforeigncurrencyE thenominalexchangerate isthepriceofforeigncurrencyintermsofdomestic P istheforeignpricelevelPisthehomepriceleveldomesticdisposableincome Yd affectthecurrentaccountthroughitseffectontotalspendingbydomesticconsumers CA CA q Yd CA EP P Yd 1 3HowRealExchangeRateChangesAffecttheCurrentAccount CA EX IMeffectsonEXRealExchangeRate sriseforeignproductsmoreexpensiveForeigndemandingmoreofourexportsEP P EX CA EP P EX CA effectsonIMIMdenotesthevalueofimportsmeasuredintermsofdomesticoutput andnotthevolumeofforeignproductsvolumeeffect shiftsonexportandimportquantitiesvalueeffect changesthedomesticoutputworthofagivenvolumeofforeignimports assume volumeeffect valueeffectEP P homecurrency IM CA EP P homecurrency IM CA 1 4HowDisposableIncomeChangesAffecttheCurrentAccount ariseinYdcausesdomesticconsumerstoincreasetheirspendingonallgoods includingimportsfromabroad Yd IM EX CA 2 TheEquationofAggregateDemand D C I G CAC C Yd C Y T CA CA EP P Yd CA EP P Y T D C Y T I G CA EP P Y T moresimplyD D EP P Y T I G Aggregatedemandisafunctionofrealexchangerate EP P disposableincome Y T investmentdemand I governmentspending G 2 1TheRealExchangeRateandAggregateDemandEP Prise domesticgoodscheaper importfalls exportrises CArises aggregatedemandDgoesup EP P EX IM CA D Arealdepreciationofthehomecurrencyraisesaggregatedemandforhomeoutput arealappreciationlowers2 2RealIncomeandAggregateDemandYdrise Crise IMrise CAfalls soDmayrise mayfallsSinceincreaseincomehavemoreeffectonconsumptionthanimportspending C CA SoDrisewhenYdrise figure16 1AggregateDemandasaFunctionofOutput 2 3HowOutputIsDeterminedIntheShortRun outputmarketisinequilibriumwhenrealoutput Y equalstheaggregatedemandfordomesticoutputY D D EP P Y T I G 4 OutputMarketEquilibrium TheDDSchedule Output theExchangeRate andOutputMarketEquilibrium whenoutputmarketequilibriumexchangerateandoutput figure16 3illustrates withfixedP andPdomesticcurrencyagainstforeigncurrency ariseinEfromE1toE2 oreigngoodsandservicesmoreexpensiveandCA andaggregatedemandscheduleupwardfromD1toD2becauseDupward OutputexpandsfromY1toY2asfirmsfindthemselvesfacedwithexcessdemand analyzetheeffectsofachangeinP orPonoutputriseintherealexchangerateEP P whetherduetoariseinE ariseinP orafallinP willcauseanupwardshiftintheaggregatedemandfunctionandanexpansionofoutput allelseequal fallinEP P willcauseadownwardshiftinaggregatedemandfunctionandoutputtocontract allelseequal 4 1DerivingtheDDSchedule DDscheduleshowsallcombinationsofoutputandtheexchangeratewhenoutputmarketisinshort runequilibrium aggregatedemand aggregateoutput FigureleftshowshowtoderivetheDDschedulewhichrelatesEandYwhenPandP arefixedPoint1ontheDDgivestheoutputlevelY1atwhichaggregatedemandequalsaggregatesupplywhentheexchangerateisE1 AdepreciationofthecurrencytoE2leadstothehigheroutputlevelY2accordingtothefigure supperpart andthisinformationallowsustolocatepoint2onDD FactorsthatShifttheDDSchedule 1 G D DDScheduletoshifttotheright figure16 5showes ariseingovernmentpurchasesfromG1toG2 givenafixedexchangerateofE E leadstoanequilibriumoutputlevelY1toY2point1isonepointonDDAnincreaseinGcausestheaggregatedemandtoshiftupwardtoanewpoint2onDDsummary aincreaseinGcausesDDtoshifttotheright Similarly adecreaseinGcausesDDtoshifttotheleft FactorsThatShifttheDDSchedule 2 AchangeinTT D DDScheduletoshifttotheleft3 AchangeinII D DDScheduletoshifttotheright4 AchangeinPP D DDScheduletoshifttotheleft5 AchangeinP P D DDScheduletoshifttotheright6 AchangeinCC D DDScheduletoshifttotheright7 AdemandshiftbetweenforeignanddomesticgoodsDemandshiftfromformforeigntodomestic D DDscheduletoshifttotheright 5 AssetMarketEquilibriumintheShortRun TheAASchedule DDscheduleshowsallexchangerateandoutputlevelsatwhichtheoutputmarketisinshort runequilibriumequilibriumintheeconomyasawholerequiresequilibriumintheassetmarketsaswellasintheoutputmarketThescheduleofexchangerateandoutputcombinationsthatareconsistentwithequilibriuminthedomesticmoneymarketandtheforeignexchangemarketiscalledtheAAschedule 5 1Output theExchangeRate andAssetMarketEquilibrium foreignexchangemarketinequilibriumInChapter13 theinterestparityconditionR R Ee E ERistheinterestrateondomesticcurrencydepositsandR istheinterestrateonforeigncurrencydepositsdomesticmoneymarketinequilibriumInChapter14 thedomesticinterestratesatisfyingtheinterestparityconditionmustalsoequatetherealdomesticmoneysupply Ms P toaggregaterealmoneydemandMs P L R Y whentheinterestratefallsaggregaterealmoneydemandL R Y risesAriseinrealoutput Y increasesrealmoneydemandbyraisingthevolumeofmonetarytransactionspeoplemustcarryoutafallinrealoutputreducesrealmoneydemandbyreducingtransactionsneeds figure16 6showes lowerpartofthefigure Y1andMs P R1clearsthehomemoneymarket point1 E1clearstheforeignexchangemarket point1 AriseinoutputfromY1toY2raisesmoneydemandschedulefromL R Y1 toL R Y2 raisetheequilibriumdomesticinterestratetoR2 point2 EeandR fixed thedomesticcurrencyappreciatefromEltoE2tobringtheforeignexchangemarketbackintoequilibriumatpoint2 summary ForassetmarketstoremaininequilibriumariseindomesticoutputmustbeaccompaniedbyanappreciationofthedomesticcurrencyY Ms P不变 R Ee P 不变 E domesticcurrency allelseequal andafallindomesticoutputmustbeaccompaniedbyadepreciation Y Ms P不变 R Ee P 不变 E domesticcurrency 5 2DerivingtheAASchedule Figure16 7showstheAAschedule AAschedulerelatesexchangeratesandoutputlevelsthatkeepthemoneyandforeignexchangemarketsinequilibriumariseinY1toY2willproduceanappreciationofthedomesticcurrency thatis afallintheexchangeratefromE1toE2 TheAAschedulethereforehasanegativeslope asshown 5 3FactorsthatShifttheAASchedule 1 AchangeinMs fixedoutput Ms domesticcurrency E AAtoshiftupward Similarly afallinMscausesAAtoshiftdownward 2 AchangeinP P realmoneysupply R E TheeffectofariseinPisthereforeadownwardshiftofAA AfallinPresultsinanupwardshiftofAA 3 AchangeinEe Ee E domesticcurrency AAshiftsupwardwhenariseintheexpectedfutureexchangerateoccurs Itshiftsdownwardwhentheexpectedfutureexchangeratefalls 2020 1 15 23 5 3FactorsthatShifttheAASchedule 4 AchangeinR R shiftsthedownward slopingscheduleatthetopofFigure16 6totheright domesticcurrencymustdepreciateE AriseinR thereforehasthesameeffectonAAasariseinEe Itcausesanupwardshift AfallinR resultsinadownwardshiftofAA 5 Achangeinrealmoneydemand AreductioninmoneydemandimpliesaninwardshiftoftheaggregaterealmoneydemandfunctionL R Y foranyfixedlevelofY anditthusresultsinalowerinterestrateandariseinE Areductioninmoneydemandthereforehasthesameeffectasanincreaseinthemoneysupply inthatitshiftsAAupward TheoppositedisturbanceofanincreaseinmoneydemandwouldshiftAAdownward Short RunEquilibriumforanOpenEconomy puttingtheDDandAASchedulesTogether Ashort runequilibriumfortheeconomyasawholemustlieonbothschedulesbringaboutequilibriumsimultaneouslyintheoutputandassetmarketsFigure16 8combinestheDDandAAschedulestolocateshort runequilibrium TheintersectionofDDandAAatpoint1istheonlycombinationofexchangerateandoutputconsistentwithboththeequalityofaggregatedemandandaggregatesupplyandassetmarketequilibrium Short RunEquilibriumforanOpenEconomy puttingtheDDandAASchedulesTogether 0 E Y1 DD 1 E1 E3 2 AA E2 3 6 TemporaryChangesinMonetaryandFiscalPolicy wecanstudyhowshiftsingovernmentmacroeconomicpoliciesaffectoutputandtheexchangerateTwotypesofgovernmentpolicy monetarypolicy worksthroughchangesinthemoneysupplyfiscalpolicy worksthroughchangesingovernmentspendingortaxesInthissectionweexaminetemporarypolicyshiftsEe orpricelevel P andthatthedomesticpricelevel P isfixedintheshortrun 6 1MonetaryPolicy AnincreasedmoneysupplyshiftsAA1upwardtoAA2 notaffectthepositionofDD Theupwardshiftoftheassetmarketequilibriumschedulemovestheeconomyfrompoint1 withexchangerateE1andoutputY1topoint2 withexchangerateE2andoutputY2 Anincreaseinthemoneysupplycausesadepreciationofthedomesticcurrency anexpansionofoutput andthereforeanincreaseinemployment 6 2fiscalpolicy AtemporaryfiscalexpansionshiftstheDDscheduletotherightbutdoesnotmoveAA Initiallytheeconomyisatpoint1 withE1andY1fiscalexpansionmovestheeconomytopoint2 causingthecurrencytoappreciatetoE2andoutputtoexpandtoY2 6 4PoliciestoMaintainFullEmployment figure16 12ashiftisadecreaseinaggregatedemandfordomesticDD1toDD2point2 thecurrencyhasdepreciatedtoE2andoutput atY2restorefullemploymentAtemporarymoneysupplyincreaseshiftstoAA2andplacestheeconomyatpoint3restoresfullemploymentbutcausesthehomecurrencytodepreciateevenfurther atemporaryincreaseinthedemandformoneydownwardshiftofAA1toAA2 frompoint1topoint2 AtemporarymoneysupplyincreaseshiftstoAA1andmovesbacktopoint1TemporaryfiscalexpansionshiftsDD1toDD2andrestoresfullemploymentatpoint3 6 5inflationBiasandOtherProblemsofPolicyFormulation 1 Stickynominalpricesnotonlygivegovernmentsthepowertoraiseoutputwhenitisabnormallylow butalsomaytemptthemtocreateapoliticallyusefuleconomicboom2 Inpracticeitissometimeshardtobesurewhetheradisturbancetotheeconomyoriginatesintheoutputorassetmarkets 3 Real worldpolicychoicesarefrequentlydeterminedbybureaucraticnecessitiesratherthanbydetailedconsiderationofwhethershockstotheeconomyarereal thatis theyoriginateintheoutputmarket ormonetary 4 Anotherproblemwithfiscalpolicyisitsimpactonthegovernmentbudget 5 Policiesthatappeartoactswiftlyinoursimplemodeloperateinrealitywithlagsofvaryinglength PermanentShiftsinMonetaryandFiscalPolicy 1 MonetaryPolicy2 FascalPolicy MonetaryPolicy ExchangrateE Yf E2 AA2 DD AA1 E1 Y1 1 2 3 OutputY Short runEffectsofAPermanentMonetaryPolicySet P P andR unchangedPermanentincreasewhentheMS theAAcurvetotheright newequilibriumpointat2 theexchangerateandoutputbothincreased andmorethanatemporaryincreaseincurrencyinwhichthelevelof3 Conclusion Theincreaseinthepermanentmoneysupply short termincreaseoutput expandemployment E Yf E1 AA2 DD1 AA1 E2 Y2 1 2 3 DD2 AA3 E3 Y Thelongterm whentheoutputabovefullemploymentlevelofY1 theriseofpricesP DDcurvetotheleft theAAcurvetotheleft untilyoupaythefullemploymentlevelofY1 point3 Conclusion Theincreaseinthepermanentmoneysupply long termprices exchangeratesrise whileoutputhasnoeffect long runsdjustmenttoAPermanentMonetaryPolicy APERMANENTFISCALEXPANSION Iftheeconomystartsatlong runequilibrium apermanentchangeinfiscalpolicyhasnoneteffectonoutput Instead itcausesanimmediateandpermanentexchangeratejumpthataffectsexactlythefiscalpolicy sdirecteffectonaggregatedemand Effectofapermanentfiscalexpansion E Y Yf AA1 DD1 DD2 1 3 2 E2 E1 AA2 PermanentreductionofthepermanentincreaseofGorT willresultintheDDcurverighttoaDD2 currencyappreciation anincreaseinoutput Meanwhile withthecurrencyappreciation theexpectedexchangeratedecline theAAcurvelefttomoveofAA2toreachanewequilibriumpoint Theexchangeratedropped thecurrencyappreciation whiletheoutputunchanged Conclusion underthefloatingexchangeratesystem the fiscalpolicyinvalidated MacroeconomicPolicyandtheCurrentAccount TheXXScheduleSupposeacountrywantstoholdadesiredlevelofcurrentaccount say X ThatisCA SP P Y T X E Y DD XX Conclusion XXcurveisthecurveofarightangle andflatthantheDDcurve EquilibriumpointintheXXcurveabovethemeantoimprovetheinternationalbalanceofpayments inthebottommeansthattheinternationalbalanceofpaymentsdeterioration meaning Referstothecurrentaccountbalanceismaintainedatacertainlevel thevariouscombinationsoftheexchangerateandoutput Shape LetCA EP P YT Xisintheotherconditionsremainunchanged Yincreaseinnetexportdemand theCAdecreased inordertomaintaintheCAconstant Emustrise thecurrencydepreciation thenetexportdemandrise MacroeconomicPolicy theCurrentAccount 1 MonetaryPol