《经济学原理第三版》微观分册原版中英文双语ppt课件13

5FIRMBEHAVIORANDTHEORGANIZATIONOFINDUSTRY企业行为与产业组织THECOSTSOFRODUCTION生产成本CHAPTER13HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCTHEMARKETFORCESOFSUPPLYANDDEMANDNSUPPLYANDDEMANDARETHETWOWORDSTHATECONOMISTSUSEMOSTOFTENNSUPPLYANDDEMANDARETHEFORCESTHATMAKEMARKETECONOMIESWORKNMODERNMICROECONOMICSISABOUTSUPPLY,DEMAND,ANDMARKETEQUILIBRIUMHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC供给与需求的市场力量N供给与需求是经济学家最常用的两个词。N供给与需求是使市场经济运行的力量。N现代微观经济学就是研究供给、需求与市场均衡的学科。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCWHATARECOSTSNACCORDINGTOTHELAWOFSUPPLYFIRMSAREWILLINGTOPRODUCEANDSELLAGREATERQUANTITYOFAGOODWHENTHEPRICEOFTHEGOODISHIGHTHISRESULTSINASUPPLYCURVETHATSLOPESUPWARDHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC什么是成本N根据供给规律当一种物品价格高时，厂商愿意生产和销售的更多。这导致供给曲线向上倾斜。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCWHATARECOSTSNTHEFIRMSOBJECTIVETHEECONOMICGOALOFTHEFIRMISTOMAXIMIZEPROFITSHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC什么是成本N企业的目标企业的经济目标是利润最大化HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCTOTALREVENUE,TOTALCOST,ANDPROFIT总收入、总成本与利润UTOTALREVENUE总收入UTHEAMOUNTTHATTHEFIRMRECEIVESFORTHESALEOFITSOUTPUT企业销售产品所得UTOTALCOST总成本UTHEMARKETVALUEOFTHEINPUTSAFIRMUSESINPRODUCTION企业用于生产的投入要素的市场价值。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCAFIRMSPROFIT公司利润PROFITISTHEFIRMSTOTALREVENUEMINUSITSTOTALCOSTPROFITTOTALREVENUETOTALCOST利润总收入总成本HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCCOSTSASOPPORTUNITYCOSTSNAFIRMSCOSTOFPRODUCTIONINCLUDESALLTHEOPPORTUNITYCOSTSOFMAKINGITSOUTPUTOFGOODSANDSERVICESNEXPLICITANDIMPLICITCOSTSAFIRMSCOSTOFPRODUCTIONINCLUDEEXPLICITCOSTSANDIMPLICITCOSTSEXPLICITCOSTSAREINPUTCOSTSTHATREQUIREADIRECTOUTLAYOFMONEYBYTHEFIRMIMPLICITCOSTSAREINPUTCOSTSTHATDONOTREQUIREANOUTLAYOFMONEYBYTHEFIRMHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC成本是机会成本N一个企业的生产成本包括生产物品与劳务量的所有机会成本。N显性成本和隐性成本一个企业的生产成本包括显性成本与隐性成本。显性成本要求企业直接支付货币的投入要素成本。隐性成本不要求企业支付货币的投入要素成本。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCECONOMICPROFITVERSUSACCOUNTINGPROFITUECONOMISTSMEASUREAFIRMSECONOMICPROFITASTOTALREVENUEMINUSALLTHEOPPORTUNITYCOSTSEXPLICITANDIMPLICITUACCOUNTANTSMEASURETHEACCOUNTINGPROFITASTHEFIRMSTOTALREVENUEMINUSONLYTHEFIRMSEXPLICITCOSTSINOTHERWORDS,THEYIGNORETHEIMPLICITCOSTSHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC经济利润与会计利润U经济学家计量企业的经济利润，即企业的总收益减去生产所销售物品和劳务的所有机会成本（显性的和隐性的）。U会计师计量企业的会计利润，即企业的总收益减去企业的显性成本。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCECONOMICPROFITVERSUSACCOUNTINGPROFIT经济利润与会计利润UWHENTOTALREVENUEEXCEEDSBOTHEXPLICITANDIMPLICITCOSTS,THEFIRMEARNSECONOMICPROFIT当总收益大于显性成本和隐性成本时，企业赚取经济利润。UECONOMICPROFITISSMALLERTHANACCOUNTINGPROFIT经济利润小于会计利润。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCECONOMICPROFITVERSUSACCOUNTINGPROFITREVENUETOTALOPPORTUNITYCOSTSHOWANECONOMISTVIEWSAFIRMEXPLICITCOSTSECONOMICPROFITIMPLICITCOSTSEXPLICITCOSTSACCOUNTINGPROFITHOWANACCOUNTANTVIEWSAFIRMREVENUEHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC经济利润与会计利润收入所有机会成本经济学家如何看企业显性成本经济利润隐性成本显性成本会计利润会计师如何看企业收入TABLE1APRODUCTIONFUNCTIONANDTOTALCOSTHUNGRYHELENSCOOKIEFACTORYCOPYRIGHT2004SOUTHWESTERNHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC表1生产函数和总成本亨格瑞海伦的糕点厂工人数量产出劳动的边际产量工厂成本工人成本投入总成本01205090504030303001020304050341201403020303030406070515010305080HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCTHEPRODUCTIONFUNCTION生产函数THEPRODUCTIONFUNCTIONSHOWSTHERELATIONSHIPBETWEENQUANTITYOFINPUTSUSEDTOMAKEAGOODANDTHEQUANTITYOFOUTPUTOFTHATGOOD生产函数用于生产一种物品的投入量与该物品产量之间的关系。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCMARGINALPRODUCT边际产量THEMARGINALPRODUCTOFANYINPUTINTHEPRODUCTIONPROCESSISTHEINCREASEINTHEQUANTITYOFOUTPUTOBTAINEDFROMANADDITIONALUNITOFTHATINPUT任何一种生产过程中的投入要素的边际产量是指增加一个单位的该要素投入所引起的产量增加。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCMARGINALPRODUCT边际产量ADDITIONALINPUT投入增加量ADDITIONALOUTPUTMARGINALPRODUCT边际产量产出增加量HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCDIMINISHINGMARGINALPRODUCTUDIMINISHINGMARGINALPRODUCTISTHEPROPERTYWHEREBYTHEMARGINALPRODUCTOFANINPUTDECLINESASTHEQUANTITYOFTHEINPUTINCREASESUEXAMPLEASMOREANDMOREWORKERSAREHIREDATAFIRM,EACHADDITIONALWORKERCONTRIBUTESLESSANDLESSTOPRODUCTIONBECAUSETHEFIRMHASALIMITEDAMOUNTOFEQUIPMENTHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC边际产量递减U边际产量递减是指一种投入要素的边际产量随着该要素投入量的增加而减少的特征。U例子由于雇佣的工人越来越多，每个新雇佣的工人对产量的贡献越来越小，这是因为有限的设备数量不能将他的潜能发挥出来。FIGURE2HUNGRYHELENSPRODUCTIONFUNCTIONQUANTITYOFOUTPUTCOOKIESPERHOUR150140130120110100908070605040302010NUMBEROFWORKERSHIRED012345PRODUCTIONFUNCTION图2亨格瑞海伦的生产函数产量COOKIESPERHOUR150140130120110100908070605040302010雇佣工人数量012345生产函数HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCDIMINISHINGMARGINALPRODUCTUTHESLOPEOFTHEPRODUCTIONFUNCTIONMEASURESTHEMARGINALPRODUCTOFANINPUT,SUCHASAWORKERUWHENTHEMARGINALPRODUCTDECLINES,THEPRODUCTIONFUNCTIONBECOMESFLATTERHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC边际产量递减U生产函数的斜率衡量了一种投入要素（比如一个工人）的边际产量。U随着工人数量增加，边际产量减少，生产函数越来越平坦。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCFROMTHEPRODUCTIONFUNCTIONTOTHETOTALCOSTCURVEUTHERELATIONSHIPBETWEENTHEQUANTITYAFIRMCANPRODUCEANDITSCOSTSDETERMINESPRICINGDECISIONSUTHETOTALCOSTCURVESHOWSTHISRELATIONSHIPGRAPHICALLYHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC从生产函数到总成本曲线U一个企业可能的生产量和它的成本之间的关系决定了它的产品定价。U用来说明生产产量和生产总成本之间关系的图被称为总成本曲线。TABLE1APRODUCTIONFUNCTIONANDTOTALCOSTHUNGRYHELENSCOOKIEFACTORYCOPYRIGHT2004SOUTHWESTERNHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC表1生产函数和总成本亨格瑞海伦的糕点厂工人数量产出劳动的边际产量工厂成本工人成本投入总成本01205090504030303001020304050341201403020303030406070515010305080HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCFIGURE3HUNGRYHELENSTOTALCOSTCURVE图3亨格瑞海伦的总成本曲线TOTALCOST总成本8070605040302010QUANTITYOFOUTPUT产量COOKIESPERHOUR020401401201008060TOTALCOSTCURVE总成本曲线HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCTHEVARIOUSMEASURESOFCOST成本的各种衡量COSTSOFPRODUCTIONMAYBEDIVIDEDINTOFIXEDCOSTSANDVARIABLECOSTS生产成本可以分为固定成本和可变成本。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCFIXEDANDVARIABLECOSTSUFIXEDCOSTSARETHOSECOSTSTHATDONOTVARYWITHTHEQUANTITYOFOUTPUTPRODUCEDUVARIABLECOSTSARETHOSECOSTSTHATDOCHANGEASTHEFIRMALTERSTHEQUANTITYOFOUTPUTPRODUCEDHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC固定成本和变动成本U固定成本不随着产量变动而变动的成本。U可变成本随着产量变动而变动的成本。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCTOTALCOSTS总成本UTOTALFIXEDCOSTSTFC总固定成本（TFC）UTOTALVARIABLECOSTSTVC总可变成本（TVC）UTOTALCOSTSTC总成本TCTCTFCTVCTABLE2THEVARIOUSMEASURESOFCOSTTHIRSTYTHELMASLEMONADESTANDCOPYRIGHT2004SOUTHWESTERNHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCTABLE2THEVARIOUSMEASURESOFCOSTTHIRSTYTHELMASLEMONADESTANDQUANTITYTOTALCOSTFIXEDCOSTVARIABLECOST0300300000133030003023803000803450300150454030024056503003506780300480793030063081100300800912903009901015003001200HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC表2成本的各种衡量索斯蒂特尔玛的柠檬水店数量总成本固定成本可变成本0300300000133030003023803000803450300150454030024056503003506780300480793030063081100300800912903009901015003001200HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCAVERAGECOSTS平均成本UAVERAGECOSTSCANBEDETERMINEDBYDIVIDINGTHEFIRMSCOSTSBYTHEQUANTITYOFOUTPUTPRODUCED平均成本总成本除以产量。UTHEAVERAGECOSTISTHECOSTOFEACHTYPICALUNITOFPRODUCT平均成本是生产一个普通单位的成本。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCFAMILYOFAVERAGECOSTS平均成本UAVERAGEFIXEDCOSTSAFC平均固定成本AFCUAVERAGEVARIABLECOSTSAVC平均可变成本AVCUAVERAGETOTALCOSTSATC平均总成本ATCATCAFCAVCHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCFAMILYOFAVERAGECOSTSHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC平均成本HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC300TABLE2THEVARIOUSMEASURESOFCOSTTHIRSTYTHELMASLEMONADESTANDQUANTITYAFCAVCATC010303302150040190310005015040750601355060070130605008013070430901338038100138903311014310030120150HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC300表2成本的各种衡量索斯蒂特尔玛的柠檬水店产量AFCAVCATC010303302150040190310005015040750601355060070130605008013070430901338038100138903311014310030120150HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCMARGINALCOSTUMARGINALCOSTMCMEASURESTHEAMOUNTTOTALCOSTRISESWHENTHEFIRMINCREASESPRODUCTIONBYONEUNITUMARGINALCOSTHELPSANSWERTHEFOLLOWINGQUESTIONUHOWMUCHDOESITCOSTTOPRODUCEANADDITIONALUNITOFOUTPUTHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC边际成本U边际成本MC衡量额外一个单位产量所引起的总成本的增加。U边际成本帮助回答以下问题U生产额外一个单位产量的成本是多少HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCMARGINALCOSTHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC边际成本HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCMARGINALCOSTTHIRSTYTHELMASLEMONADESTANDHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC边际成本索斯蒂特尔玛的柠檬水店FIGURE4THIRSTYTHELMASTOTALCOSTCURVESTOTALCOST150014001300120011001000900800700600500400300200100QUANTITYOFOUTPUTGLASSESOFLEMONADEPERHOUR014327659810TOTALCOSTCURVE图4索斯蒂特尔玛的总成本曲线总成本150014001300120011001000900800700600500400300200100产量每小时柠檬水杯数014327659810总成本曲线FIGURE5THIRSTYTHELMASAVERAGECOSTANDMARGINALCOSTCURVESCOSTS350325300275250225200175150125100075050025QUANTITYOFOUTPUTGLASSESOFLEMONADEPERHOUR014327659810MCATCAVCAFC图5索斯蒂特尔玛的平均成本和边际成本曲线成本350325300275250225200175150125100075050025产量每小时柠檬水杯数014327659810MCATCAVCAFCHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCCOSTCURVESANDTHEIRSHAPES成本曲线及其形状MARGINALCOSTRISESWITHTHEAMOUNTOFOUTPUTPRODUCED边际成本随着产量增加而上升。MARGINALCOST边际成本UTHISREFLECTSTHEPROPERTYOFDIMINISHINGMARGINALPRODUCT边际成本递增反映了边际产量递减的性质FIGURE5THIRSTYTHELMASAVERAGECOSTANDMARGINALCOSTCURVESCOSTS350325300275250225200175150125100075050025QUANTITYOFOUTPUTGLASSESOFLEMONADEPERHOUR014327659810MC图5索斯蒂特尔玛的平均成本和边际成本曲线成本350325300275250225200175150125100075050025产量每小时柠檬水杯数）014327659810MCHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCCOSTCURVESANDTHEIRSHAPESTHEAVERAGETOTALCOSTCURVEISUSHAPEDUATVERYLOWLEVELSOFOUTPUTAVERAGETOTALCOSTISHIGHBECAUSEFIXEDCOSTISSPREADOVERONLYAFEWUNITSUAVERAGETOTALCOSTDECLINESASOUTPUTINCREASESUAVERAGETOTALCOSTSTARTSRISINGBECAUSEAVERAGEVARIABLECOSTRISESSUBSTANTIALLYHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC成本曲线及其形状平均总成本曲线是U型的。U在产量水平极低时，平均总成本高，这是因为固定成本只分摊在少数几个单位产品上。U平均总成本随着产量增加而降低。U当平均可变成本大幅度上升时，平均总成本开始增加。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCCOSTCURVESANDTHEIRSHAPES成本曲线及其形状THEBOTTOMOFTHEUSHAPEOCCURSATTHEQUANTITYTHATMINIMIZESAVERAGETOTALCOSTTHISQUANTITYISSOMETIMESCALLEDTHEEFFICIENTSCALEOFTHEFIRM在使平均总成本最小的产量时，U型曲线的底部就出现了。这种产量有时被称为企业的有效规模。FIGURE5THIRSTYTHELMASAVERAGECOSTANDMARGINALCOSTCURVESCOSTS350325300275250225200175150125100075050025QUANTITYOFOUTPUTGLASSESOFLEMONADEPERHOUR014327659810ATC图5索斯蒂特尔玛的平均成本和边际成本曲线成本350325300275250225200175150125100075050025产量每小时柠檬水杯数014327659810ATCHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCRELATIONSHIPBETWEENMARGINALCOSTANDAVERAGETOTALCOSTUWHENEVERMARGINALCOSTISLESSTHANAVERAGETOTALCOST,AVERAGETOTALCOSTISFALLINGUWHENEVERMARGINALCOSTISGREATERTHANAVERAGETOTALCOST,AVERAGETOTALCOSTISRISINGHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC边际成本和平均总成本之间的关系U只要边际成本小于平均总成本，平均总成本就下降。U只要边际成本大于平均总成本，平均总成本就上升。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCRELATIONSHIPBETWEENMARGINALCOSTANDAVERAGETOTALCOSTTHEMARGINALCOSTCURVECROSSESTHEAVERAGETOTALCOSTCURVEATTHEEFFICIENTSCALEUEFFICIENTSCALEISTHEQUANTITYTHATMINIMIZESAVERAGETOTALCOSTHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC边际成本和平均总成本之间的关系边际成本曲线与平均总成本曲线相交于有效规模时。U有效规模使平均总成本最小的产量。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCMCATCRELATIONSHIPBETWEENMARGINALCOSTANDAVERAGETOTALCOST000050100150200250300350024681012QUANTITYOFOUTPUTGLASSESOFLEMONADEPERHOURCOSTSHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCMCATC边际成本和平均总成本之间的关系000050100150200250300350024681012产量每小时柠檬水杯数成本边际成本平均总成本HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCTYPICALCOSTCURVES典型的成本曲线ITISNOWTIMETOEXAMINETHERELATIONSHIPSTHATEXISTBETWEENTHEDIFFERENTMEASURESOFCOST现在讨论一下不同衡量方式的成本之间的关系。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCBIGBOBSCOSTCURVESHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC大鲍伯的成本曲线FIGURE6BIGBOBSCOSTCURVESATOTALCOSTCURVE18001600140012001000800600400QUANTITYOFOUTPUTBAGELSPERHOURTC4268141210200TOTALCOST0图6大鲍伯的成本曲线A总成本曲线18001600140012001000800600400产量每小时百吉圈TC4268141210200总成本0FIGURE6BIGBOBSCOSTCURVESBMARGINALANDAVERAGECOSTCURVESQUANTITYOFOUTPUTBAGELSPERHOURCOSTS30025020015010005004268141210MCATCAVCAFC图6大鲍伯的成本曲线B边际和平均成本曲线成本30025020015010005004268141210MCATCAVCAFC产量每小时百吉圈HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCTYPICALCOSTCURVESNTHREEIMPORTANTPROPERTIESOFCOSTCURVESMARGINALCOSTEVENTUALLYRISESWITHTHEQUANTITYOFOUTPUTTHEAVERAGETOTALCOSTCURVEISUSHAPEDTHEMARGINALCOSTCURVECROSSESTHEAVERAGETOTALCOSTCURVEATTHEMINIMUMOFAVERAGETOTALCOSTHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC典型的成本曲线N成本曲线的三个重要特征随着产量增加，边际成本最终要上升。平均总成本曲线是U型的。边际成本曲线与平均总成本曲线在平均总成本最低点相交。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCCOSTSINTHESHORTRUNANDINTHELONGRUNUFORMANYFIRMS,THEDIVISIONOFTOTALCOSTSBETWEENFIXEDANDVARIABLECOSTSDEPENDSONTHETIMEHORIZONBEINGCONSIDEREDUINTHESHORTRUNSOMECOSTSAREFIXEDUINTHELONGRUNFIXEDCOSTSBECOMEVARIABLECOSTSHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC短期与长期成本U对许多企业来说，总成本分为固定和可变成本取决于所考察的时间长短。U在短期中一些成本是固定的。U在长期中成本都是可变的。HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCCOSTSINTHESHORTRUNANDINTHELONGRUN短期与长期成本BECAUSEMANYCOSTSAREFIXEDINTHESHORTRUNBUTVARIABLEINTHELONGRUN,AFIRMSLONGRUNCOSTCURVESDIFFERFROMITSSHORTRUNCOSTCURVES由于许多成本在短期中是固定的，但在长期中是可变的，所以企业的长期成本曲线不同于其短期成本曲线。FIGURE7AVERAGETOTALCOSTINTHESHORTANDLONGRUNQUANTITYOFCARSPERDAY0AVERAGETOTALCOST1,20012,000ATCINSHORTRUNWITHSMALLFACTORYATCINSHORTRUNWITHMEDIUMFACTORYATCINSHORTRUNWITHLARGEFACTORYATCINLONGRUN图7短期与长期的平均成本COPYRIGHT2004SOUTHWESTERN每天汽车产量01,20012,000小型工厂短期ATC中型工厂短期ATC大型工厂短期ATC长期ATC平均总成本HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCECONOMIESANDDISECONOMIESOFSCALEUECONOMIESOFSCALEOCCURWHENLONGRUNAVERAGETOTALCOSTDECLINESASOUTPUTINCREASESUDISECONOMIESOFSCALEOCCURWHENLONGRUNAVERAGETOTALCOSTRISESASOUTPUTINCREASESUCONSTANTRETURNSTOSCALEOCCURWHENLONGRUNAVERAGETOTALCOSTDOESNOTVARYASOUTPUTINCREASESHARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INC规模经济与规模不经济U当长期平均总成本随着产量增加而减少时，可以说存在规模经济。U当长期平均总成本随着产量增加而增加时，可以说存在规模不经济。U当长期平均总成本不随着产量变动而变动时，可以说存在规模收益不变。FIGURE7AVERAGETOTALCOSTINTHESHORTANDLONGRUNQUANTITYOFCARSPERDAY0AVERAGETOTALCOST1,20012,0001,00010,000ECONOMIESOFSCALEATCINSHORTRUNWITHSMALLFACTORYATCINSHORTRUNWITHMEDIUMFACTORYATCINSHORTRUNWITHLARGEFACTORYATCINLONGRUNDISECONOMIESOFSCALECONSTANTRETURNSTOSCALE图7短期与长期的平均总成本每天汽车产量01,20012,0001,00010,000规模经济小型工厂短期ATC中型工厂短期ATC大型工厂短期ATC长期ATC规模不经济规模收益不变T平均总成本HARCOURT,INCITEMSANDDERIVEDITEMSCOPYRIGHT2001BYHARCOURT,INCSUMMARYUTHEGOALOFFIRMSISTOMAXIMIZEPROFIT,WHICHEQUALSTOTALREVENUEMINUSTOTALCOSTUWHENANALYZINGAFIRMSBEHAVIOR,ITISIMPORTANTTOINCLUDEA