国外厂商理论讲稿.ppt

TheTheoryoftheFirm TheTheoryoftheFirm ProductionFunction ProductionFunction Statestherelationshipbetweeninputsandoutputs Inputs thefactorsofproductionclassifiedas Land allnaturalresourcesoftheearth notjust terrafirma Pricepaidtoacquireland RentLabour allphysicalandmentalhumaneffortinvolvedinproduction Pricepaidtolabour WagesCapital buildings machineryandequipmentnotusedforitsownsakebutforthecontributionitmakestoproduction Pricepaidforcapital Interest ProductionFunction Inputs Process Output Land Labour Capital Productorservicegenerated valueadded AnalysisofProductionFunction ShortRun Intheshortrunatleastonefactorfixedinsupplybutallotherfactorscapableofbeingchanged Reflectswaysinwhichfirmsrespondtochangesinoutput demand Canincreaseordecreaseoutputusingmoreorlessofsomefactorsbutsomelikelytobeeasiertochangethanothers Increaseintotalcapacityonlypossibleinthelongrun AnalysisofProductionFunction ShortRun Intimesofrisingsales demand firmscanincreaselabourandcapitalbutonlyuptoacertainlevel theywillbelimitedbytheamountofspace Inthisexample landisthefixedfactorwhichcannotbealteredintheshortrun AnalysisofProductionFunction ShortRun Ifdemandslowsdown thefirmcanreduceitsvariablefactors inthisexampleitreducesitslabourandcapitalbutagain landisthefactorwhichstaysfixed AnalysisofProductionFunction ShortRun Ifdemandslowsdown thefirmcanreduceitsvariablefactors inthisexample itreducesitslabourandcapitalbutagain landisthefactorwhichstaysfixed AnalysingtheProductionFunction LongRun Thelongrunisdefinedastheperiodoftimetakentovaryallfactorsofproduction Bydoingthis thefirmisabletoincreaseitstotalcapacity notjustshorttermcapacityAssociatedwithachangeinthescaleofproductionTheperiodoftimevariesaccordingtothefirmandtheindustry Inelectricitysupply thetimetakentobuildnewcapacitycouldbemanyyears foramarketstallholder the longrun couldbeaslittleasafewweeksormonths AnalysisofProductionFunction LongRun Inthelongrun thefirmcanchangeallitsfactorsofproductionthusincreasingitstotalcapacity Inthisexampleithasdoubleditscapacity ProductionFunction Mathematicalrepresentationoftherelationship Q f K L La Output Q isdependentupontheamountofcapital K Land L andLabour La used Costs Costs Inbuyingfactorinputs thefirmwillincurcostsCostsareClassifiedas Fixedcosts coststhatarenotrelateddirectlytoproduction rent rates insurancecosts admincosts Theycanchangebutnotinrelationtooutput VariableCosts costsdirectlyrelatedtovariationsinoutput Rawmaterialsprimarily Costs TotalCost thesumofallcostsincurredinproductionTC FC VCAverageCost thecostperunitofoutputAC TC OutputMarginalCost thecostofonemoreoronefewerunitsofproductionMC TCn TCn 1units Costs Shortrun DiminishingmarginalreturnsresultsfromaddingsuccessivequantitiesofvariablefactorstoafixedfactorLongrun Increasesincapacitycanleadtoincreasing decreasingorconstantreturnstoscale Revenue Revenue Totalrevenue thetotalamountreceivedfromsellingagivenoutputTR PxQAverageRevenue theaverageamountreceivedfromsellingeachunitAR TR QMarginalrevenue theamountreceivedfromsellingoneextraunitofoutputMR TRn TRn 1units Profit Profit Profit TR TCTherewardforenterpriseProfitshelpintheprocessofdirectingresourcestoalternativeusesinfreemarketsRelatingpricetocostshelpsafirmtoassessprofitabilityinproduction Profit NormalProfit theminimumamountrequiredtokeepafirminitscurrentlineofproductionAbnormalorSupernormalprofit profitmadeoverandabovenormalprofitAbnormalprofitmayexistinsituationswherefirmshavemarketpowerAbnormalprofitsmayindicatetheexistenceofwelfarelossesCouldbetaxedawaywithoutalteringresourceallocation Profit Sub normalProfit profitbelownormalprofitFirmsmaynotexitthemarketevenifsub normalprofitsmadeiftheyareabletocovervariablecostsCostofexitmaybehighSub normalprofitmaybetemporary orperceivedassuch Profit AssumptionthatfirmsaimtomaximiseprofitMaynotalwaysholdtrue thereareotherobjectivesProfitmaximisingoutputwouldbewhereMC MR Profit Why Cost Revenue Output MR MR theadditiontototalrevenueasaresultofproducingonemoreunitofoutput thepricereceivedfromsellingthatextraunit MC MC ThecostofproducingONEextraunitofproduction 100 Assumeoutputisat100units TheMCofproducingthe100thunitis20 TheMRreceivedfromsellingthat100thunitis150 Thefirmcanaddthedifferenceofthecostandtherevenuereceivedfromthat100thunittoprofit 130 20 150 Ifthefirmdecidestoproduceonemoreunit the101st theadditiontototalcostisnow18 theadditiontototalrevenueis140 thefirmwilladd128toprofit itisworthexpandingoutput 101 18 140 30 120 Theprocesscontinuesforeachsuccessiveunitproduced ProvidedtheMCislessthantheMRitwillbeworthexpandingoutputasthedifferenceb