LikeanEconomist宏觀經(jīng)濟學(xué)-加州大學(xué)-詹姆斯·布

LikeanEconomist(宏觀經(jīng)濟學(xué)-加州大學(xué)-詹姆斯·布LikeanEconomist(宏觀經(jīng)濟學(xué)-加州大學(xué)-詹姆斯LikeanEconomist(宏觀經(jīng)濟學(xué)-加州大學(xué)-詹姆斯·布LikeanEconomist(宏觀經(jīng)濟學(xué)-加州大學(xué)-詹姆斯·布TheImportanceofExpectations:AnExampleThestockmarketcrashof1929changedwhatAmericansexpectedaboutthefutureoftheeconomyExpectationsthatfutureincomewouldbelowerbecamerealizedspendingproductionlayoffsincome4Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.TheImportanceofExpectationsFigure3.1-TheStockMarket,1928-19325Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.Figure3.1-TheStockMarket,Economicsisaquantitativescienceusesarithmetictomeasureeconomicvariablesofinterestusesmathematicalmodelstorelateeconomicvariablesofinterestinvolvesaparticularwayofthinkingabouttheworldusinguniquetechnicallanguageaspecificsetofdata6Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.EconomicsisaquantitativesciEconomistsuseaspecialsetofanalogiesandmetaphorstodescribethefunctioningofthemacroeconomycurves“shift”moneyhasa“velocity”thecentralbank“pushestheeconomyupthePhillipscurve”7Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.EconomistsuseaspecialsetofFigure3.2-PushingtheEconomyUpthePhillipsCurve8Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.Figure3.2-PushingtheEconoDominantConceptstheimageofthe“circularflowofeconomicactivity”theuseoftheword“market”theideaof“equilibrium”useofgraphsanddiagramsequationsdepictedbygeometriccurvessituationsofequilibriumoccurwherecurvescrosschangesineconomydemonstratedbyshiftsinthecurves9Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.DominantConceptstheimageofTheCircularFlowpatternsofspending,income,andproductionflowingthroughtheeconomyflowofpurchasingpower10Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.TheCircularFlowpatternsofsTheCircularFlow“incomeside”firmsbuythefactorsofproductionfromhouseholdsmoneypaymentsflowfromfirmstohouseholds“expenditureside”householdsbuygoodsandservicesfromfirmsmoneypaymentsflowfromhouseholdstofirms11Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.TheCircularFlow“incomeside”Figure3.3-TheCircularFlowDiagram12Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.Figure3.3-TheCircularFlowCircularFlowcanbemadetobemorerealisticbyaddingthegovernmentfinancialmarketsinternationaltradeandfinance13Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.CircularFlowcanbemadetobeFigure3.4-TheCircularFlowof

EconomicActivity14Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.Figure3.4-TheCircularFlowDifferentMeasuresoftheCircularFlow“expenditureside”measureconsumptioninvestmentgovernmentpurchasesnetexports“incomeside”measurepurchasesoflabor,capital,andnaturalresourcesowneddirectlyorindirectlybyhouseholds15Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.DifferentMeasuresoftheCircDifferentMeasuresoftheCircularFlow“usesofincome”measurewherehouseholdsdecidetousetheirincomesavingtaxesconsumption16Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.DifferentMeasuresoftheCircMarketsareusedasametaphorforthecomplexprocessesofmatchingandexchangethattakeplaceintheeconomyeconomistsassumethatbuyersandsellersarewell-informedaboutprevailingpricesandquantities17Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.MarketsareusedasametaphorEquilibriumisapoint(orpoints)ofbalanceatwhichsomeeconomicquantityisneitherrisingnorfallingonceequilibriumisidentified,economistscandeterminehowfasteconomicforceswillpushtheeconomytothepointsofequilibrium18Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.Equilibriumisapoint(orpoinGraphsandEquationsanalgebraicequationrelatingtwovariablescanalsoberepresentedasacurvedrawnonagraphthesolutiontoasetoftwoequationsisthepointonagraphwherethetwocurvesthatrepresenttheequationsintersect19Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.GraphsandEquationsanalgebraFigure3.5-TwoFormsoftheProductionFunction20Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.Figure3.5-TwoFormsoftheUsingGraphsInsteadofEquationsbehavioralrelationshipsbecomecurvesthatshiftaroundonagraphconditionsofeconomicequilibriumcanberepresentedbythepointswherethecurvesdescribingbehavioralrelationshipsintersect21Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.UsingGraphsInsteadofEquatiUsingGraphsInsteadofEquationschangesinthestateoftheeconomycanbeshownasmovementsintheintersectionofthecurves22Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.UsingGraphsInsteadofEquatiBuildingModelsrestricttheproblemtoonlyafewbehavioralrelationshipsandequilibriumconditionscapturetheserelationshipsandequilibriumconditionsinsimplealgebraicequationsusediagramstorepresenttheequationsapplythemodeltotherealworld23Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingModelsrestricttheprImportantConceptsinMacroeonomicModelsrepresentativeagentsassumethatallparticipantsintheeconomyarethesameexaminethedecision-makingofoneindividualandthengeneralizetotheeconomyasawhole24Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.ImportantConceptsinMacroeonImportantConceptsinMacroeonomicModelsopportunitycostsoccurwhenanydecisionismademeasuredbythevalueofthebestalternativeforegone25Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.ImportantConceptsinMacroeonImportantConceptsinMacroeonomicModelsexpectationformationmacroeconomicmodelsmustexplaintheamountoftimepeoplespendthinkingaboutthefuturetheinformationthatpeoplehaveavailabletherulesofthumbusedtoturninformationintoexpectations26Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.ImportantConceptsinMacroeonImportantConceptsinMacroeonomicModelsexpectationformationstaticexpectationsdecisionmakersdonotthinkaboutthefutureadaptiveexpectationsdecisionmakersassumethatthefutureisgoingtobeliketherecentpast27Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.ImportantConceptsinMacroeonImportantConceptsinMacroeonomicModelsexpectationformationrationalexpectationsdecisionmakersspendasmuchtimeastheycanthinkingaboutthefutureandknowasmuchaboutthestructureandbehavioroftheeconomyasthemodelbuilderdoes28Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.ImportantConceptsinMacroeonBuildingandSolvinganEconomicModelwriteequationsthatrepresentbehavioralrelationshipsstatehowthe“effects”arerelatedtothe“causes”drawadiagramtohelpvisualizetherelationshipconsiderequilibriumconditionscanbeshownasintersectionsondiagram29Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomBuildingandSolvinganEconomicModel:AnExampleTheproductionfunctionrelatestheeconomy’scapital-laborratio(K/L)theleveloftechnologyorefficiencyofthelaborforce(E)thelevelofrealGDPperworker(Y/L)Cobb-Douglasproductionfunction30Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomBuildingandSolvinganEconomicModel:AnExampleEquilibriumconditionforbalancedgrowththeratiooftheeconomy’scapitalstock(K)toitslevelofoutput(Y)mustbeconstant31Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomBuildingandSolvinganEconomicModel:AnExampleEquilibriumconditionforbalancedgrowths=shareoftotalincomeintheeconomysavedandinvestedn=proportionalgrowthrateofthelaborforceg=proportionalgrowthrateoftheefficiencyofthelaborforce=thedepreciationrate32Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomBuildingandSolvinganEconomicModel:AnExamplearithmeticcanbeusedtodeterminethesteady-stateoutputperworkerLetE=$10,000,=1/2,s=25%,n=1%,g=1%,and=3%.33Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomBuildingandSolvinganEconomicModel:AnExamplesinceK/Y=5,thismustimplythatK/L=5Y/LsubstitutingforandEtintheCobb-Douglasproductionfunction34Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomBuildingandSolvinganEconomicModel:AnExampleinequilibrium,bothconditionsmusthold35Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomBuildingandSolvinganEconomicModel:AnExamplealgebracanbeusedtodeterminethesteady-stateoutputperworker36Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomBuildingandSolvinganEconomicModel:AnExampleputtinginthebalanced-growthcondition37Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomBuildingandSolvinganEconomicModel:AnExampleLetE=$10,000,=1/2,s=25%,n=1%,g=1%,and=3%38Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomBuildingandSolvinganEconomicModel:AnExamplegraphscanalsobeusedtoshowthesteady-stateoutputperworkertheproductionfunctioncanbedrawnwithoutputperworker(Y/L)ontheverticalaxisandcapitalperworker(K/L)onthehorizontalaxistheequilibriumconditionforbalancedgrowthcanalsobeshownK/L=s/(n+g+)

39Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.BuildingandSolvinganEconomFigure3.6-EquilibriumOutputperWorker40Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.Figure3.6-EquilibriumOutpuTheAdvantagesofUsingAlgebrabestwaytosummarizecause-and-effectbehavioralrelationshipsallowsustoconsiderdifferentpossiblesystematicrelationshipsbychangingthevalueofparameters41Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.TheAdvantagesofUsingAlgebrFigure3.7-ASingleEquation,aHost

ofRelationships42Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.Figure3.7-ASingleEquationFigure3.8-ChangingParameterValuesandtheShapeoftheCobb-DouglasProductionFunction43Copyright?2002byTheMcGraw-HillCompanies,Inc.Allrightsreserved.Figure3.8-ChangingParameteFigure3.9-TheEffectofChangesintheEfficiencyofLaborontheShapeoftheProductionFunction44Copyright?2002byTheMcGraw-Hill