曼昆《经济学原理》macroeconomic--(汉魅HanMei―经济金融类汇总分享)

Copyright©2004South-Western32AMacroeconomicTheoryoftheOpenEconomyCopyright©2004South-WesternOpenEconomies•Anopeneconomyisonethatinteractsfreelywithothereconomiesaroundtheworld.Copyright©2004South-WesternKeyMacroeconomicVariablesinanOpenEconomy•Theimportantmacroeconomicvariablesofanopeneconomyinclude:•netexports•netforeigninvestment•nominalexchangerates•realexchangeratesCopyright©2004South-WesternBasicAssumptionsofaMacroeconomicModelofanOpenEconomy•Themodeltakestheeconomy’sGDPasgiven.•Themodeltakestheeconomy’spricelevelasgiven.Copyright©2004South-WesternSUPPLYANDDEMANDFORLOANABLEFUNDSANDFORFOREIGN-CURRENCYEXCHANGE•TheMarketforLoanableFundsS=I+NCO•Attheequilibriuminterestrate,theamountthatpeoplewanttosaveexactlybalancesthedesiredquantitiesofinvestmentandnetcapitaloutflows.Copyright©2004South-WesternTheMarketforLoanableFunds•Thesupplyofloanablefundscomesfromnationalsaving(S).•Thedemandforloanablefundscomesfromdomesticinvestment(I)andnetcapitaloutflows(NCO).Copyright©2004South-WesternTheMarketforLoanableFunds•Thesupplyanddemandforloanablefundsdependontherealinterestrate.•Ahigherrealinterestrateencouragespeopletosaveandraisesthequantityofloanablefundssupplied.•Theinterestrateadjuststobringthesupplyanddemandforloanablefundsintobalance.Figure1TheMarketforLoanableFundsCopyright©2003Southwestern/ThomsonLearningQuantityofLoanableFundsRealInterestRateSupplyofloanablefunds(fromnationalsaving)Demandforloanablefunds(fordomesticinvestmentandnetcapitaloutflow)EquilibriumquantityEquilibriumrealinterestrateCopyright©2004South-WesternTheMarketforLoanableFunds•Attheequilibriuminterestrate,theamountthatpeoplewanttosaveexactlybalancesthedesiredquantitiesofdomesticinvestmentandnetforeigninvestment.Copyright©2004South-WesternTheMarketforForeign-CurrencyExchange•Thetwosidesoftheforeign-currencyexchangemarketarerepresentedbyNCOandNX.•NCOrepresentstheimbalancebetweenthepurchasesandsalesofcapitalassets.•NXrepresentstheimbalancebetweenexportsandimportsofgoodsandservices.Copyright©2004South-WesternTheMarketforForeign-CurrencyExchange•Inthemarketforforeign-currencyexchange,U.S.dollarsaretradedforforeigncurrencies.•Foraneconomyasawhole,NCOandNXmustbalanceeachotherout,or:NCO=NXCopyright©2004South-WesternTheMarketforForeign-CurrencyExchange•Thepricethatbalancesthesupplyanddemandforforeign-currencyistherealexchangerate.Copyright©2004South-WesternTheMarketforForeign-CurrencyExchange•Thedemandcurveforforeigncurrencyisdownwardslopingbecauseahigherexchangeratemakesdomesticgoodsmoreexpensive.•Thesupplycurveisverticalbecausethequantityofdollarssuppliedfornetcapitaloutflowisunrelatedtotherealexchangerate.Figure2TheMarketforForeign-CurrencyExchangeCopyright©2003Southwestern/ThomsonLearningQuantityofDollarsExchangedintoForeignCurrencyRealExchangeRateSupplyofdollars(fromnetcapitaloutflow)Demandfordollars(fornetexports)EquilibriumquantityEquilibriumrealexchangerateCopyright©2004South-WesternTheMarketforForeign-CurrencyExchange•Therealexchangerateadjuststobalancethesupplyanddemandfordollars.•Attheequilibriumrealexchangerate,thedemandfordollarstobuynetexportsexactlybalancesthesupplyofdollarstobeexchangedintoforeigncurrencytobuyassetsabroad.Copyright©2004South-WesternEQUILIBRIUMINTHEOPENECONOMY•Inthemarketforloanablefunds,supplycomesfromnationalsavinganddemandcomesfromdomesticinvestmentandnetcapitaloutflow.•Inthemarketforforeign-currencyexchange,supplycomesfromnetcapitaloutflowanddemandcomesfromnetexports.Copyright©2004South-WesternEQUILIBRIUMINTHEOPENECONOMY•Netcapitaloutflowlinkstheloanablefundsmarketandtheforeign-currencyexchangemarket.•Thekeydeterminantofnetcapitaloutflowistherealinterestrate.Figure3HowNetCapitalOutflowDependsontheInterestRateCopyright©2003Southwestern/ThomsonLearning0NetCapitalOutflowNetcapitaloutflowisnegative.Netcapitaloutflowispositive.RealInterestRateCopyright©2004South-WesternEQUILIBRIUMINTHEOPENECONOMY•Pricesintheloanablefundsmarketandtheforeign-currencyexchangemarketadjustsimultaneouslytobalancesupplyanddemandinthesetwomarkets.•Astheydo,theydeterminethemacroeconomicvariablesofnationalsaving,domesticinvestment,netforeigninvestment,andnetexports.Figure4TheRealEquilibriuminanOpenEconomyCopyright©2003Southwestern/ThomsonLearning(a)TheMarketforLoanableFunds(b)NetCapitalOutflowNetcapitaloutflow,NCORealInterestRateRealInterestRate(c)TheMarketforForeign-CurrencyExchangeQuantityofDollarsQuantityofLoanableFundsNetCapitalOutflowRealExchangeRateSupplySupplyDemandDemandrrECopyright©2004South-WesternHOWPOLICIESANDEVENTSAFFECTANOPENECONOMY•Themagnitudeandvariationinimportantmacroeconomicvariablesdependonthefollowing:•Governmentbudgetdeficits•Tradepolicies•PoliticalandeconomicstabilityCopyright©2004South-WesternGovernmentBudgetDeficits•Inanopeneconomy,governmentbudgetdeficits...•reducethesupplyofloanablefunds,•driveuptheinterestrate,•crowdoutdomesticinvestment,•causenetforeigninvestmenttofall.Figure5TheEffectsofGovernmentBudgetDeficitCopyright©2003Southwestern/ThomsonLearning(a)TheMarketforLoanableFunds(b)NetCapitalOutflowRealInterestRateReal