曼昆经济学原理第二章

Copyright©2004South-Western/ThomsonLearning2ThinkingLikeanEconomistCopyright©2004South-Western/ThomsonLearningThinkingLikeanEconomist•Everyfieldofstudyhasitsownterminology•Mathematics•integralsaxiomsvectorspaces•Psychology•egoidcognitivedissonance•Law•promissoryestoppeltortsvenues•Economics•supplyopportunitycostelasticityconsumersurplusdemandcomparativeadvantagedeadweightlossCopyright©2004South-Western/ThomsonLearningThinkingLikeanEconomist•Economicstrainsyouto....•Thinkintermsofalternatives.•Evaluatethecostofindividualandsocialchoices.•Examineandunderstandhowcertaineventsandissuesarerelated.Copyright©2004South-Western/ThomsonLearningTHEECONOMISTASASCIENTIST•Theeconomicwayofthinking...•Involvesthinkinganalyticallyandobjectively.•Makesuseofthescientificmethod.Copyright©2004South-Western/ThomsonLearningTheScientificMethod:Observation,Theory,andMoreObservation•Usesabstractmodelstohelpexplainhowacomplex,realworldoperates.•Developstheories,collects,andanalyzesdatatoevaluatethetheories.Copyright©2004South-Western/ThomsonLearningTheRoleofAssumptions•Economistsmakeassumptionsinordertomaketheworldeasiertounderstand.•Theartinscientificthinkingisdecidingwhichassumptionstomake.•Economistsusedifferentassumptionstoanswerdifferentquestions.Copyright©2004South-Western/ThomsonLearningEconomicModels•Economistsusemodelstosimplifyrealityinordertoimproveourunderstandingoftheworld•Twoofthemostbasiceconomicmodelsinclude:•TheCircularFlowDiagram•TheProductionPossibilitiesFrontierCopyright©2004South-Western/ThomsonLearningOurFirstModel:TheCircular-FlowDiagram•Thecircular-flowdiagramisavisualmodeloftheeconomythatshowshowdollarsflowthroughmarketsamonghouseholdsandfirms.Figure1TheCircularFlowCopyright©2004South-WesternSpendingGoodsandservicesboughtRevenueGoodsandservicessoldLabor,land,andcapitalIncome=Flowofinputsandoutputs=FlowofdollarsFactorsofproductionWages,rent,andprofitFIRMS•Produceandsellgoodsandservices•Hireandusefactorsofproduction•Buyandconsumegoodsandservices•OwnandsellfactorsofproductionHOUSEHOLDS•Householdssell•FirmsbuyMARKETSFORFACTORSOFPRODUCTION•Firmssell•HouseholdsbuyMARKETSFORGOODSANDSERVICESCopyright©2004South-Western/ThomsonLearningOurFirstModel:TheCircular-FlowDiagram•Firms•Produceandsellgoodsandservices•Hireandusefactorsofproduction•Households•Buyandconsumegoodsandservices•OwnandsellfactorsofproductionCopyright©2004South-Western/ThomsonLearningOurFirstModel:TheCircular-FlowDiagram•MarketsforGoodsandServices•Firmssell•Householdsbuy•MarketsforFactorsofProduction•Householdssell•FirmsbuyCopyright©2004South-Western/ThomsonLearningOurFirstModel:TheCircular-FlowDiagram•FactorsofProduction•Inputsusedtoproducegoodsandservices•Land,labor,andcapitalCopyright©2004South-Western/ThomsonLearningOurSecondModel:TheProductionPossibilitiesFrontier•Theproductionpossibilitiesfrontierisagraphthatshowsthecombinationsofoutputthattheeconomycanpossiblyproducegiventheavailablefactorsofproductionandtheavailableproductiontechnology.Figure2TheProductionPossibilitiesFrontierCopyright©2003Southwestern/ThomsonLearningProductionpossibilitiesfrontierABCQuantityofCarsProduced2,2006001,00030007002,0003,0001,000QuantityofComputersProducedDCopyright©2004South-Western/ThomsonLearningOurSecondModel:TheProductionPossibilitiesFrontier•ConceptsIllustratedbytheProductionPossibilitiesFrontier•Efficiency•Tradeoffs•OpportunityCost•EconomicGrowthFigure3AShiftintheProductionPossibilitiesFrontierCopyright©2004South-WesternEQuantityofCarsProduced2,0007002,10075004,0003,0001,000QuantityofComputersProducedACopyright©2004South-Western/ThomsonLearningMicroeconomicsandMacroeconomics•Microeconomicsfocusesontheindividualpartsoftheeconomy.•Howhouseholdsandfirmsmakedecisionsandhowtheyinteractinspecificmarkets•Macroeconomicslooksattheeconomyasawhole.•Economy-widephenomena,includinginflation,unemployment,andeconomicgrowthCopyright©2004South-Western/ThomsonLearningTHEECONOMISTASPOLICYADVISOR•Wheneconomistsaretryingtoexplaintheworld,theyarescientists.•Wheneconomistsaretryingtochangetheworld,theyarepolicyadvisor.Copyright©2004South-Western/ThomsonLearningPOSITIVEVERSUSNORMATIVEANALYSIS•Positivestatementsarestatementsthatattempttodescribetheworldasitis.•Calleddescriptiveanalysis•Normativestatementsarestatementsabouthowtheworldshouldbe.•CalledprescriptiveanalysisCopyright©2004South-Western/ThomsonLearning•PositiveorNormativeStatements?•Anincreaseintheminimumwagewillcauseadecreaseinemploymentamongtheleast-skilled.POSITIVE•Higherfederalbudgetdeficitswillcauseinterestratestoincrease.POSITIVE??POSITIVEVERSUSNORMATIVEANALYSIS?Copyright©2004South-Western/ThomsonLearning•PositiveorNormativeStatements?•Theincomegainsfromahigherminimumwageareworthmorethananyslightreductionsinemployment.NORMATIVE•Stategovernmentsshouldbeallowedtocollectfromtobaccocompaniesthecostsoftreatingsmoking-relatedillnessesamongthepoor.NORMATIVE??POSITIVEVERSUSNORMATIVEANALYSIS?Copyright©2004South-Western/ThomsonLearningEconomistsinWashington•...serveasadvisersinthepolicymakingprocessofthethreebranchesof