曼昆宏观经济学第三十二篇答案.docx

曼昆宏观经济学第三十二篇答案.docx

《曼昆宏观经济学第三十二篇答案.docx》由会员分享，可在线阅读，更多相关《曼昆宏观经济学第三十二篇答案.docx（12页珍藏版）》请在冰豆网上搜索。

曼昆宏观经济学第三十二篇答案

SOLUTIONSTOTEXTPROBLEMS:

QuickQuizzes

1.Thesupplyofloanablefundscomesfromnationalsaving.Thedemandforloanablefundscomesfromdomesticinvestmentandnetcapitaloutflow.Supplyinthemarketforforeign-currencyexchangecomesfromnetcapitaloutflow.Demandinthemarketforforeign-currencyexchangecomesfromnetexports.

2.Thetwomarketsinthemodeloftheopeneconomyarethemarketforloanablefundsandthemarketforforeign-currencyexchange.Thesemarketsdeterminetworelativeprices:

（1）themarketforloanablefundsdeterminestherealinterestrate;and

（2）themarketforforeign-currencyexchangedeterminestherealexchangerate.

3.IfAmericansdecidedtospendasmallerfractionoftheirincomes,theincreaseinsavingwouldshiftthesupplycurveforloanablefundstotheright,asshowninFigure1.Thedeclineintherealinterestrateincreasesnetcapitaloutflowandshiftsthesupplyofdollarstotherightinthemarketforforeign-currencyexchange.Theresultisadeclineintherealexchangerate.Sincetherealinterestrateislower,domesticinvestmentincreases.Sincenetcapitaloutflowincreases,thetradebalancealsoincreases.Overall,savinganddomesticinvestmentincrease,therealinterestrateandrealexchangeratedecrease,andthetradebalanceincreases.

Figure1

QuestionsforReview

1.Thesupplyofloanablefundscomesfromnationalsaving;thedemandforloanablefundscomesfromdomesticinvestmentandnetcapitaloutflow.Thesupplyofdollarsinthemarketforforeignexchangecomesfromnetcapitaloutflow;thedemandfordollarsinthemarketforforeignexchangecomesfromnetexports.Thelinkbetweenthetwomarketsisnetcapitaloutflow.

2.Governmentbudgetdeficitsandtradedeficitsaresometimescalledthetwindeficitsbecauseagovernmentbudgetdeficitoftenleadstoatradedeficit.Thegovernmentbudgetdeficitleadstoreducednationalsaving,causingtheinterestratetoincrease,thusreducingnetcapitaloutflow,whichinturnreducesnetexports.

3.IfaunionoftextileworkersencouragespeopletobuyonlyAmerican-madeclothes,importswouldbereduced,sonetexportswouldincreaseforanygivenrealexchangerate.Thiswouldcausethedemandcurveinthemarketforforeignexchangetoshifttotheright,asshowninFigure2.Theresultisariseintherealexchangerate,butnoeffectonthetradebalance.Thetextileindustrywouldimportless,butotherindustries,suchastheautoindustry,wouldimportmorebecauseofthehigherrealexchangerate.

Figure2

4.Capitalflightisalargeandsuddenmovementoffundsoutofacountry.Capitalflightcausestheinterestratetoincreaseandtheexchangeratetodepreciate.

ProblemsandApplications

1.JapangenerallyrunsatradesurplusbecausetheJapanesesavingrateishighrelativetoJapanesedomesticinvestment.Theresultishighnetcapitaloutflow,whichismatchedbyhighnetexports,resultinginatradesurplus.Theotherpossibilities（highforeigndemandforJapanesegoods,lowJapanesedemandforforeigngoods,andstructuralbarriersagainstimportsintoJapan）wouldaffecttherealexchangerate,butnotthetradesurplus.

2.AreductionintheU.S.governmentbudgetdeficitwouldincreasenationalsaving,shiftingthesupplycurveofloanablefundstotherightinFigure3.ThiswouldreducetherealinterestrateintheUnitedStates,thusincreasingnetcapitaloutflow,andreducingtherealexchangerate.Thustherealvalueofthedollarwoulddecline,notincreaseasthepresidentsuggested.

Figure3

3.IfCongresspassesaninvestmenttaxcredit,itsubsidizesdomesticinvestment.Thedesiretoincreasedomesticinvestmentleadsfirmstoborrowmore,increasingthedemandforloanablefunds,asshowninFigure4.Thisraisestherealinterestrate,thusreducingnetcapitaloutflow.Thedeclineinnetcapitaloutflowreducesthesupplyofdollarsinthemarketforforeignexchange,raisingtherealexchangerate.Thetradebalancealsodeclines,sincenetcapitaloutflow,hencenetexports,arelower.Thehigherrealinterestratealsoincreasesthequantityofnationalsaving.Insummary,savingincreases,domesticinvestmentincreases,netcapitaloutflowdeclines,therealinterestrateincreases,therealexchangerateincreases,andthetradebalancedecreases.

Figure4

4.a.AdeclineinthequalityofU.S.goodsatagivenrealexchangeratewouldreducenetexports,reducingthedemandfordollars,thusshiftingthedemandcurvefordollarstotheleftinthemarketforforeignexchange,asshowninFigure5.

b.Theshifttotheleftofthedemandcurvefordollarsleadstoadeclineintherealexchangerate.Sincenetcapitaloutflowisunchanged,andnetexportsequalsnetcapitaloutflow,thereisnochangeinequilibriuminnetexportsorthetradebalance.

c.Theclaiminthepopularpressisincorrect.AchangeinthequalityofU.S.goodscannotleadtoariseinthetradedeficit.Thedeclineintherealexchangeratemeansthatwegetfewerforeigngoodsinexchangeforourgoods,soourstandardoflivingmaydecline.

Figure5

5.Areductioninrestrictionsofimportswouldreducenetexportsatanygivenrealexchangerate,thusshiftingthedemandcurvefordollarstotheleft.Theshiftofthedemandcurvefordollarsleadstoadeclineintherealexchangerate,whichincreasesnetexports.Sincenetcapitaloutflowisunchanged,andnetexportsequalsnetcapitaloutflow,thereisnochangeinequilibriuminnetexportsorthetradebalance.Butbothimportsandexportsrise,soexportindustriesbenefit.

6.a.WhentheFrenchdevelopastrongtasteforCaliforniawines,thedemandfordollarsintheforeign-currencymarketincreasesatanygivenrealexchangerate,asshowninFigure6.

b.Theresultoftheincreaseddemandfordollarsisariseintherealexchangerate.

c.Thequantityofnetexportsisunchanged.

Figure6

7.Anexportsubsidyincreasesnetexportsatanygivenrealexchangerate.Thiscausesthedemandfordollarstoshifttotherightinthemarketforforeignexchange,asshowninFigure7.Theeffectisahigherrealexchangerate,butnochangeinnetexports.Sothesenatoriswrong;anexportsubsidywillnotreducethetradedeficit.

Figure7

8.HigherrealinterestratesinEuropeleadtoincreasedU.S.netcapitaloutflow.Highernetcapitaloutflowleadstohighernetexports,sinceinequilibriumnetexportsequalnetcapitaloutflow（NX=NCO）.Figure8showsthattheincreaseinnetcapitaloutflowleadstoalowerrealexchangerate,higherrealinterestrate,andincreasednetexports.

Figure8

9.a.IftheelasticityofU.S.netcapitaloutflowwithrespecttotherealinterestrateisveryhigh,thelowerrealinterestratethatoccursbecauseoftheincreaseinprivatesavingwillincreasenetcapitaloutflowagreatdeal,soU.S.domesticinvestmentwillnotincreasemuch.

b.Sinceanincreaseinprivatesavingreducestherealinterestrate,inducinganincreaseinnetcapitaloutflow,therealexchangeratewilldecline.IftheelasticityofU.S.exportswithrespecttotherealexchangerateisverylow,itwilltakealargedeclineintherealexchangeratetoincreaseU.S.netexportsbyenoughtomatchtheincreaseinnetcapitaloutflow.

10.a.IftheJapanesedecidedtheynolongerwantedtobuyU.S.assets,U.S.netcapitaloutflowwouldincrease,increasingthedemandforloanablefunds,asshowninFigure9.TheresultisariseinU.S.interestrates,anincreaseinthequantityofU.S.saving（becauseofthehigherinterestrate）,andlowerU.S.domesticinvestment.

b.Inthemarketforforeignexchange,therealexchangeratedeclinesandthebalanceoftradeincreases.

Figure9

11.TheflighttosafetyledtoadesirebyforeignerstobuyU.S.governmentbonds,resultinginadeclineinU.S.netcapitaloutflow,asshowninFigure10.Thedeclineinnetcapitaloutflowalsomeansadeclineinthedemandforloanablefunds.Asthefigureshows,theshifttotheleftinthedemandcurveresultsinadeclineintherealinterestrateintheUnitedStates.Inaddition,thedecreaseinnetcapitaloutflowdecreasesthesupplyofdollarsintheforeign-exchangemarket,causingthedollartoappreciate,shownasariseintherealexchangerate.Thelowerrealinterestratecausesnationalsavingtodecline,butincreasesdomesticinvestment.Sincenetcapitaloutflowislower,netexportsarelower,thusthetradebalancedeclines.

Figure10

12.a.WhenU.S.mutualfundsbecomemoreinterestedininvestinginCanada,CanadiannetcapitaloutflowdeclinesastheU.S.mutualfundsmakeportfolioinvestmentsinCanadianstocksandbonds.Thedemandforloanablefundsshiftstotheleftandthenetcapitaloutflowcurveshiftstotheleft,asshowninFigure11.Asthefigureshows,therealinterestratedeclines,thusreducingCanada’sprivatesaving,butincreasingCanada’sdomesticinvestment.Inequilibrium,Canadiannetcapitaloutflowdeclines.

b.SinceCanada'sdomesticinvestmentincreases,inthelongrun,Canada'scapitalstockwillincrease.

c.Withahighercapitalstock,Canadianworkerswillbemoreproductive（thevalueoftheirmarginalproductwillincrease）sowageswillrise.ThusCanadianworkerswillbebetteroff.

d.TheshiftofinvestmentintoCanadameansincreasedU.S.netcapitaloutflow.Asaresult,theU.S.realinterestrises,leadingtolessdomesticinvestment,whichinthelongrunreducestheU.S.capitalstock,lowersthevalueofmarginalproductofU.S.workers,andthereforedecreasesthewagesof

U.S.workers.TheimpactonU.S.citizenswouldbedifferentfromtheimpactonU.S.workersbecausesomeU.S.citizensowncapitalthatn