斯蒂芬D威廉森宏观经济学第三版第十五章Stephen D. Williamsons Macroeco

Copyright©2008PearsonAddison-Wesley.Allrightsreserved.Chapter15Money,InflationandBankingCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-2Chapter15Topics•Alternativeformsofmoney.•Moneyandtheabsenceofdoublecoincidenceofwants.•Thecausesandeffectsoflong-runinflation.•Financialintermediationandbanking.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-3AlternativeFormsofMoney•Commoditymoney•Circulatingprivatebanknotes•Commodity-backedpapercurrency•Fiatmoney•TransactionsdepositsatbanksCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-4TheDouble-CoincidenceProblemandtheRoleofMoney•Barterexchangeisdifficultinhighly-developed,specializedeconomies.•Economicexchangerequiressearchcosts,andthesecostsarehighwheneconomicagentsarespecializedinconsumptionandproduction,andcanonlytradeagoodorserviceforanothergoodorservice.•Searchcostsarereduceddramaticallyifeveryoneacceptsmoneyinexchangeforgoodsandservices.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-5Figure15.1AnAbsence-of-Double-CoincidenceEconomyCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-6Figure15.2Good1asaCommodityMoneyintheAbsence-of-Double-CoincidenceEconomyCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-7Figure15.3FiatMoneyintheAbsence-of-Double-CoincidenceEconomyCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-8TheEffectsofLong-RunInflation•UsethemonetaryintertemporalmodelfromChapter10.•Showthatmoneyisnotsuperneutral–highermoneygrowthcauseshigherinflation,whichaffectsrealeconomicvariables.•Anincreaseinthemoneygrowthrateincreasestheinflationrateandthenominalinterestrate,andreducesemploymentandoutput.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-9Figure15.4ScatterplotoftheInflationRatevs.theGrowthRateinM0fortheUnitedStates,1960–2006Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-10Equation15.1Assumethatthecentralbankcausesthemoneysupplytogrowataconstantrate.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-11Equation15.2Inequilibrium,moneysupplyequalsmoneydemand.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-12Equation15.3Moneysupplyalsoequalsmoneydemandinthefutureperiod.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-13Equation15.4Combinetheprevioustwoequations.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-14Equation15.5Theconsumer’sintertemporalmarginalcondition.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-15Equation15.6Marginalconditionreflectingtheconsumer’stradeoffbetweencurrentleisureandfutureconsumption:Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-16Equation15.7Marginalconditionreflectingtheconsumer’stradeoffbetweencurrentleisureandcurrentconsumption:Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-17Figure15.5TheLong-RunEffectsofanIncreaseintheMoneyGrowthRateCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-18TheFriedmanRule•Inflationcausesaninefficiency,inthatitdistortsintertemporaldecisions.•TheFriedmanruleisaprescriptionformonetarygrowththateliminatestheinefficiencycausedbyinflation.•TheFriedmanrulespecifiesthatthemoneystockgrowataratethatmakesthenominalinterestratezero.•Inpractice,nocentralbankappearstohaveadoptedaFriedmanruletoguidemonetarypolicy.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-19Equation15.9ParetooptimalityrequiresthatCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-20Equation15.10Inacompetitiveequilibrium,Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-21Equation15.11Also,inacompetitiveequilibrium,Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-22PropertiesofAssets•Rateofreturn•Risk•Maturity•LiquidityCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-23DefiningCharacteristicsofFinancialIntermediaries1.Borrowfromonegroupofeconomicagentsandlendtoanother.2.Well-diversifiedwithrespecttobothassetsandliabilities.3.Transformassets.4.Processinformation.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-24TheDiamond-DybvigBankingModel•Threeperiods,0,1,and2.•Twotypesofconsumers:early(consumeinperiod1)andlate(consumeinperiod2)•Efficienteconomicarrangementisforconsumerstosetupabankinordertosharerisk.•Giventhebank’sdepositcontract,thebankisopentoarun,whichisabadequilibrium.Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-25Figure15.6TheUtilityFunctionForaConsumerintheDiamond–DybvigModelCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-26Figure15.7ThePreferencesofaDiamond–DybvigConsumerCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-27Equation15.12•ThemarginalrateofsubstitutionofearlyconsumptionforlateconsumptionisCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-28Equation15.13•FirstconstraintthatadepositcontractmustsatisfyisCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-29Equation15.14SecondconstraintthatadepositcontractmustsatisfyisCopyright©2008PearsonAddison-Wesley.Allrightsreserved.15-30Equation15.15Combinethetwoconstraintstogetone:Copyright©2008PearsonAddison-Wesley.Allrightsreserved.15-31Equation15.16