forFactorInputs(微观经济学-华侨大学,JeffCaldw

Chapter14MarketsforFactorInputsChapter14Slide2TopicstobeDiscussedCompetitiveFactorMarketsEquilibriuminaCompetitiveFactorMarketFactorMarketswithMonopsonyPowerFactorMarketswithMonopolyPowerChapter14Slide3CompetitiveFactorMarketsCharacteristics1)Largenumberofsellersofthefactorofproduction2)Largenumberofbuyersofthefactorofproduction3)ThebuyersandsellersofthefactorofproductionarepricetakersChapter14Slide4CompetitiveFactorMarketsDemandforaFactorInputWhenOnlyOneInputIsVariableDemandforfactorinputsisaderiveddemand…derivedfromfactorcostandoutputdemandChapter14Slide5CompetitiveFactorMarketsAssumeTwoinputs:Capital(K)andLabor(L)CostofKisrandthecostoflaboriswKisfixedandLisvariableDemandforaFactorInputWhenOnlyOneInputIsVariableChapter14Slide6CompetitiveFactorMarketsProblemHowmuchlabortohireDemandforaFactorInputWhenOnlyOneInputIsVariableChapter14Slide7CompetitiveFactorMarketsMeasuringtheValueofaWorker’sOutputMarginalRevenueProductofLabor(MRPL)MRPL=(MPL)(MR)DemandforaFactorInputWhenOnlyOneInputIsVariableChapter14Slide8CompetitiveFactorMarketsAssumeperfectcompetitionintheproductmarketThenMR=PDemandforaFactorInputWhenOnlyOneInputIsVariableChapter14Slide9CompetitiveFactorMarketsQuestionWhatwillhappentothevalueofMRPLwhenmoreworkersarehired?DemandforaFactorInputWhenOnlyOneInputIsVariableChapter14Slide10MarginalRevenueProductHoursofWorkWages($perhour)MRPL=MPLxPCompetitiveOutputMarket(P=MR)MRPL=MPLxMRMonopolisticOutputMarket(PMR)Chapter14Slide11CompetitiveFactorMarketsChoosingtheprofit-maximizingamountoflaborIfMRPLw(themarginalcostofhiringaworker):hiretheworkerIfMRPLw:hirelesslaborIfMRPL=w:profitmaximizingamountoflaborDemandforaFactorInputWhenOnlyOneInputIsVariableChapter14Slide12w*SLInacompetitivelabormarket,afirmfacesaperfectlyelasticsupplyoflaborandcanhireasmanyworkersasitwantsatw*.HiringbyaFirmintheLaborMarket(withCapitalFixed)QuantityofLaborPriceofLaborWhynothirefewerormoreworkersthanL*.MRPL=DLL*TheprofitmaximizingfirmwillhireL*unitsoflaboratthepointwherethemarginalrevenueproductoflaborisequaltothewagerate.Chapter14Slide13CompetitiveFactorMarketsIfthemarketsupplyoflaborincreasedrelativetodemand(babyboomersorfemaleentry),asurplusoflaborwouldexistandthewageratewouldfall.QuestionHowwouldthisimpactthequantitydemandedforlabor?DemandforaFactorInputWhenOnlyOneInputIsVariableChapter14Slide14AShiftintheSupplyofLaborQuantityofLaborPriceofLaborw1S1MRPL=DLL1w2L2S2Chapter14Slide15CompetitiveFactorMarketsComparingInputandOutputMarketsproductionofMCMPMPMRMR))((MPMRPworkersofnumbermaximizingprofitatandMR))(MP(MRPLLLLLLComparingInputandOutputMarketsInbothmarkets,inputandoutputchoicesoccurwhereMR=MCMRfromthesaleoftheoutputMCfromthepurchaseoftheinputChapter14Slide17CompetitiveFactorMarketsScenarioProducingfarmequipmentwithtwovariableinputs:LaborAssembly-linemachineryAssumethewageratefallsDemandforaFactorInputWhenSeveralInputsAreVariableChapter14Slide18CompetitiveFactorMarketsQuestionHowwillthedecreaseinthewagerateimpactthedemandforlabor?DemandforaFactorInputWhenSeveralInputsAreVariableChapter14Slide19MRPL1MRPL2Whentwoormoreinputsarevariable,afirm’sdemandforoneinputdependsonthemarginalrevenueproductofbothinputs.Firm’sDemandCurveforLabor(withVariableCapital)HoursofWorkWages($perhour)051015204080120160Whenthewagerateis$20,Arepresentsonepointonthefirm’sdemandforlaborcurve.Whenthewageratefallsto$15,theMRPcurveshifts,generatinganewpointConthefirm’sdemandforlaborcurve.ThusAandCareonthedemandforlaborcurve,butBisnot.DLABCChapter14Slide20AssumethatallfirmsrespondtoalowerwageAllfirmswouldhiremoreworkers.Marketsupplywouldincrease.Themarketpricewillfall.Thequantitydemandedforlaborbythefirmwillbesmaller.CompetitiveFactorMarketsIndustryDemandforLaborMRPL1TheIndustryDemandforLaborLabor(worker-hours)Labor(worker-hours)Wage($perhour)Wage($perhour)05101505101550100150L0L2DL1Horizontalsumifproductpriceunchanged120MRPL2L1IndustryDemandCurveDL2FirmIndustryChapter14Slide22TheIndustryDemandforLaborQuestionHowwouldachangetoanon-competitivemarketimpactthederivationofthemarketdemandforlabor?Chapter14Slide23TheDemandforJetFuelObservationsJetfuelisafactor(input)costCostofjetfuel1971--Jetfuelcostequaled12.4%oftotaloperatingcost1980--Jetfuelcostequaled30.0%oftotaloperatingcost1990’s--Jetfuelcostequaled15.0%oftotaloperatingcostChapter14Slide24TheDemandforJetFuelObservationsAirlinesrespondedtohigherpricesinthe1970’sbyreducingthequantityofjetfuelusedTon-milesincreasedby29.6%&jetfuelconsumedroseby8.8%Chapter14Slide25TheDemandforJetFuelObservationsThedemandforjetfuelimpactstheairlinesandrefineriesalikeTheshort-runpriceelasticityofdemandforjet-fuelisveryinelasticChapter14Slide26Short-runPriceElasticityofDemandforJetFuelAmerican-.06Delta-.15Continental-.09TWA-.10Northwest-.07United-.10AirlineElasticityAirlineElasticityChapter14Slide27TheDemandforJetFuelQuestionHowwouldthelong-runpriceelasticityofdemandcomparetotheshort-run?Chapter14Slide28TheShort-andLong-RunDemandforJet