AP微观经济学7

11.ResourcemarketswithapplicationstolaborMPP,MRP,MFCMarginalphysicalproduct(MPP):theadditionaloutputproducedasonemoreunitoflaborisadded.Marginalrevenueproduct(MRP):theadditiontothefirm’srevenueastheresultofanadditionaloutputforanadditionalunitoflaborMRP=MPP×PriceoftheproductMarginalfactorcost(MFC):theadditionalcostforeachadditionalunitoflaborhiredWageelasticityofdemandWageelasticityofdemand=Thehigherthepriceelasticityofdemandfortheproduct,thehigherthiswageelasticityTheJapcarsintheUSraisedboththetwoelasticityThehighertheproportionof[laborcosts:totalcostsofproduction],thehigherthiselasticityHighereducationvs.oilrefineryindustryThegreaterthenumberofsubstituteresourcesavailable,thehigherthiswageelasticityRobotscansubstituteforlaborratewage%ΔlaborfordemandedQuantity%ΔLaborcostsProfitsPerfectlycompetitivelabormarketWage$UnitsoflaborWED=MRPLDSE1.Thefirmisaprice-taker2.MFCstaysthesameinthismarkettype3.Profitmax:MRPL=MFCLa.Firmb.MarketS=ACL=MFCLWage$Case:securityguardsNo.ofguardsaddedTotalvalueofbookssavedMRPL1$80080021,10030031,30020041,40010051,45050Thesecurityguardsarepaid$120perday(MFCL=120)Abookstoreobservesthatforeachadditionalsecurityguardhired,thereissomereductioninthenumberofbooksstolen.Howmanyguardsshouldbestbehired?Choosethehighestleveloflaborunitsclosetothepoint:MRPL=MFCLWheneverthewagerateisconstant,thereisaperfectlycompetitiveresourcemarket.ImperfectlycompetitivelabormarketUnitsoflaborMFCLS=ACL=wagerateEWage$D=MRPLCWCWEWMMXMXCWorkershavetoselllabortoonlyonefirmMFCLACLFindtheprofitmaxpoint:1.LetMFCL=MRPL2.FindXM3.DropalineontoScurve4.FindWMWMonopolyWCompetitiveXMonopolyXCompetitiveCostmin&ProfitmaxInthehireofmorethanoneresource:L-labor,K-capitalCostminimization:Inperfectlycompetitiveresourcemarket:Profitmaximization:Inperfectlycompetitiveresourcemarket:KKLLMFCMPPMFCMPPKKLLPMPPPMPP1MFCMRPMFCMRPKKLL1PMRPPMRPKKLLShiftsindemandforaresourceDemandforaresource=MRPofthatresourceMRPL=MPPL×PXTheDemandcurve→,if:WorkersbegintoproducemoreperhourPriceoftheproductincreasesThenumberofbuyersoftheresourcesincreasesThepriceofsubstitutesforlaborbecomeshigherSupplyofresourcesWage$UnitsoflaborWESLDSLBThisisalabor-leisuretrade-offa.Normalb.BackwardbendingWage$Low-incomeworkersprefermoremoneyHigh-incomeworkersfavormoreleisureTransferearningandrentsAxiom:isthatwemustpaythesuppliers(worker)hiscostsinordertoexpecthimtocontinuehissupplyoflabor.Transferearning:whataworkercouldhaveearnedelsewhere,justtheopportunitycostfortheworker.Thetransferearningistheminpricewemustpaytoassureacontinuingsupplyoflabor.Rents:paymentsthatworkersreceivethatareinexcessofthetransferearnings,orinexcessofwhatworkerscouldearnelsewhere.ShiftsinsupplydeterminantsAttractivenessofanoccupation:→Thenumberoflaborsuppliers:→Therelativeprices(if↑)ofcompetingusesofaresource:Theresourceitself:←Thesubstituteresource:→Whypeoplehavedifferentwages?Notalljobsareequallyattractive:wepaymoretopeopleinunattractivejobs.Innatedifferences:somejobskillsarenecessaryforsomehigh-payingjobs.Humancapital:higherinvestmentinhumancapitalleadstohigherreturnsinincome.Compensatingwagedifferentials:higher-riskjobreceiveshigherpay.Psychicincome:somepeoplehavehigherpsychicincomeinexchangeforlowermonetaryincome.Discrimination:manywagedifferentialsareduetoage,gender,sex,race,etcImmobility:wedon’tallmovetothebestjobs.Labormarketimperfections:wagesinamonopolylabormarketislowerthaninacompetitivelabormarketGovernmentinterference:minwage,wagesubsidiesIncomeinequalityTotalincome%LineofproportionalincomePopulation%LorenzcurveThegreaterthedifferencebetweenthetwolines,thegreaterthedegreeofincomeinequality100100