Lecture 7.ppt

LOGO LectureSevenDecisionMaking NANCHUNCAI2011 11 14 Today sAgenda examinethefirms behaviour Thistopicwillgiveyouabetterunderstandingofwhatdecisionsliebehindthesupplycurveinamarket Toexaminewhatincludedintheindustry stotalcostToanalyzetherelationshipbetweenthetotalcostandproductionTounderstandtherelationshipbetweenthetotalcostandmarginandhowtheyinteractToconsidertheshapesoftypicalcostcurvesToinvestigatetherelationshipbetweentheshort runandlong runcost 在实现这些目的后 你应该能 解释经济利润和会计利润之间的区别利用生产函数推导出总成本曲线解释为什么边际成本曲线必定在平均总成本最低点与平均总成本曲线相交解释为什么生产函数会在产量水平低时表现出边际产量递增 而在产量水平高时表现出边际产量递减解释为什么随着企业扩大其生产规模 它倾向于首先表现出规模经济 然后规模收益不变 以后规模不经济 Prologue Inthischapterandtheonesthatfollow weexaminefirmbehaviorinmoredetail Thistopicwillgiveyouabetterunderstandingofwhatdecisionsliebehindthesupplycurveinamarket Inaddition itwillintroduceyoutoapartofeconomicscalledindustrialorganization thestudyofhowfirms decisionsregardingpricesandquantitiesdependonthemarketconditionstheyface Howdoesthisdifferenceinthenumberoffirmsaffectthepricesinthesemarketsandtheefficiencyofthemarketoutcomes Thefieldofindustrialorganizationaddressesexactlythisquestion TypesofEnterprises 企业或厂商 SoleProprietorship业主制 individualenterprisePartnership 合伙制Corporation 公司制State ownedenterprise Nationalizedbusiness 国有企业 两种公司的区别 公司制 经营权 监督权 所有权 决策权 董事会 经理层 监事会 股东大会 国有企业的产权安排 产权的分解困境 董事会 经理层 股东会 国资委 审议数量 审议动力 责任能力 内部控制 如果学生能在经济学课程中真正理解了成本以及成本的所有各个方面 那么 这门课程就算取得了真正的成功 JohnMauriceClark 1884 1963 TheFirm sobjectiveTheeconomicgoalofthefirmistomaximizeprofitsMaximizeprofits HungryHelen sCookieFactory亨格瑞 海伦糕点厂Flour sugar spicesthBreadmachine ovenEmployees Whatisafirm sprofit 什么是企业的利润 CostsasopportunitycostOpportunitycostiswhatyoumustgiveupinordertogetit Economist Afirm scostofproductionincludesalltheopportunitycostsofmakingitsoutputofgoodsandservices 企业生产成本包括生产物品与劳务量的所有机会成本 HungryHelen sCookieFactory亨格瑞 海伦糕点厂 买面粉花了1000美元糕点工人的工资海伦放弃程序员工作 100美元 小时 ExplicitandimplicitcostAfirm scostofproductionincludesexplicitandimplicitcosts Explicitcost 显性成本involvesadirectmoneyoutlayforfactorsofproduction Tangibleandpredictable显性成本 需要企业支出货币的投入成本Implicitcost 隐性成本doesnotinvolveadirectmoneyoutlay Intangibleandinevitable隐性成本 不需要企业支出货币的投入成本 EconomicprofitsVersusAccountingprofits经济利润与会计利润Economistsconcernhowfirmsmakedecisionsaboutwhattoproduceandpricingpolicywhicharebasedontheexplicitandimplicitcost Thoughwhentheymeasureafirm seconomiccost theyusuallytakeexplicitandimplicitcostintoaccount Accountantsmeasuretheaccountingcostthatonlyconsidertheexplicitcost EconomicprofitsVersusAccountingprofitsEconomicprofitofabusinessisthefirm stotalrevenueminusalltheopportunitycosts explicitandimplicit ofproducingthegoodsandservicessold 经济利润 企业的总收益减生产所销售物品与劳务的所有机会成本2 Accountingprofitofabusinessisthefirm stotalrevenueminusonlythefirm sexplicitcosts会计利润 企业的总收益只减企业的显性成本3 Depreciation reductioninvalue4 Economicprofitisusuallysmallerthanaccountingprofit EconomicprofitsVersusAccountingprofitsHowaneconomistHowanaccountantviewafirmviewafirmTotalRevenueTotalTotalopportunityRevenuecosts Economicprofit ImplicitCost ExplicitCost Accountingprofit ExplicitCost Capital资本Twopatternscostofcapital 资本的两种成本形态 资本的实物成本形态与资本的隐性成本Thecapitalofabusinessisthevalueofitsasset equipments buildings tools inventory andfinancialassets Theimplicitcostofcapitalistheopportunitycostofcapitalusedbyabusiness theincometheownercouldhaverealizedfromthatcapitalifithadbeenusedinitsnextbestalternativeway Topurchasethecookiefactorywillneed300 000 农民麦当纳讲授钢琴课每小时20美元 有一天他在自己的土地上用10个小时种了价值100美元的种子 他引起的机会成本是多少 他的会计师衡量的成本是多少 如果这些种子将带来价值200美元的作物 麦当纳赚了多少会计利润 他赚到了经济利润吗 即问即答 CheckyourunderstandingP229Question1ExplicitCost thoseareoutlayofmoneyImplicitCost Ifthebasementisusedinotherways likerentingtosomeoneelse theimplicitcostisthatmoneyforgone Otherwise theimplicitcostiszero ExplicitCostImplicitcostImplicitcost Productionandcost ToinvestigatetherelationshipbetweenthetotalcostandtheproductionoftheenterpriseHungryHelen sCookieFactoryasanexample HungryHelen sCookieFactory亨格瑞 海伦糕点厂 生产函数TheProductionFunction Assumption ThescaleofHungry scookiefactoryisfixedHungrycanonlychangethenumberofworkerstoproducedifferentquantityofcookies HungryHelen sCookieFactory亨格瑞 海伦糕点厂 APRODUCTIONFUNCTIONANDTOTALCOST HUNGRYHELEN SCOOKIEFACTORY Hungry scookiefactory Theproductionfunction 亨格瑞 海伦的生产函数HUNGRYHELEN SPRODUCTIONFUNCTION Quantityof Output cookies perhour 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 NumberofWorkersHired 0 1 2 3 4 5 Productionfunction生产函数 TheproductionFunction生产函数Theproductionfunctionistherelationshipbetweenthequantityofinputsafirmusesandthequantityofoutputitproduces 生产函数是表示在一定时期内 在技术水平不变的情况下 生产一种物品的投入量与该物品产量之间的关系 MarginalProduct 边际产量 istheadditionalquantityofoutputthatisproducedbyusingonemoreunitofthatinput 增加一个单位的投入所引起的产量增加 Marginalproductoflabor changeinquantityofoutputproducedbyoneadditionalunitoflabor ChangeinquantityofoutputChangeinquantityoflaborOrQMPL LThetotalproductcurveshowstherelationshipbetweentheinputandoutput AdditionalOutputMarginalproduct AdditionalInputDiminishingMarginalProductDiminishingmarginaloutputisthepovertywherebythemarginalproductofaninputdeclinesasthequantityoftheinputincreases 边际产量递减 一种投入的边际产量随着投入量增加而减少的特征Examples Asmoreandmoreworkersarehiredatafirm eachadditionalworkercontributeslessandlesstoproductionbecausethefirmhasalimitedamountofequipment DiminishingMarginalproductTheslopeoftheproductionfunctionmeasuresthemarginalproductofaninput suchasaworker 向上量生产函数的斜率 向前量生产函数的斜率用来衡量边际产量Whenthemarginalproductdeclines theproductionfunctionbecomesflatter FromtheProductionFunctiontotheTotal CostCurveTheTotalcostcurveistherelationshipbetweenthequantityafirmcanproduceanditscostsdeterminespricingdecisions Hungry scookiefactory Theproductionfunctionandtotalcost HUNGRYHELEN STOTAL COSTCURVE Total Cost 80 70 60 50 40 30 20 10 QuantityofOutput cookiesperhour 0 20 40 140 120 100 80 60 Total cost curve Cost 80 70 60 50 40 30 20 10 QuantityofOutput 0 Total cost curve Quantityof Output cookies perhour 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 NumberofWorkersHired 0 1 2 3 4 5 Productionfunction生产函数 如果农民琼斯没有在她的土地上播种 他就得不到收成 如果她种一袋种子 他得到3斤小麦 如果他种2袋种子 他得到5斤小麦 如果他种3袋种子 他得到6斤小麦 一袋种子的成本是100美元 而且 种子是他惟一的成本 用这些数据画出该农民的生产函数和总成本曲线 解释它们的形状 即问即答 Howmuch Vs Eitheror Decision howmuch eg Howmanyworkersshouldyouhireinyourcompany Howmanyhoursyouwillspendonreading eitheror eg Eithertogotothelibraryorstayinthedorm Eithertogotothecanteenororderapizza Marginalanalysisinvolvescomparingthebenefitofdoingalittlebitmoreofsomeactivitywithcostofdoingalittlebitmoreofthatactivity Marginalcost边际成本Themarginalcostofproducingagoodorserviceistheadditionalcostincurredbyproducingonemoreunitofthatgoodorservice 生产一件物品或劳务的边际成本是指增加额外的一个单位的物品或劳务 Babette smarginalincreasingportionsize 0 80 MC MarginalCost Quantity MC MarginalCost Quantity Increasingmarginalcost递增的边际成本 wheneachadditionalunitcostsmoretoproducethanthepreviousone Themarginalcostcurveshowstherelationshipbetweenmarginalcostandthequantityofthegoodalreadyproduced MarginalBenefitsThemarginalbenefitofproducingagoodorserviceistheadditionalbenefitderivedfromproducingonemoreunitofthatgoodorservice Thereisdecreasingmarginalbenefitfromanactivitywheneachadditionalunitoftheactivityproduceslessbenefitsthanthepreviousunit Themarginalbenefitcurveshowshowthebenefitfromproducingonemoreunitdependsonthequantitythathasalreadybeenproduced 边际效益曲线显示如何从生产多一个单位效益取决于已经生产出来的数量 MB Marginalbenefit Quantity MB MarginalBenefitMarginalCost Quantity MC 6 4 5 Optimalquantity MarginalAnalysisOptimalQuantityisthequantitythatgeneratesthemaximumpossibletotalnetgain Theprincipleofmarginalanalysissaysthattheoptimalquantityisthequantityatwhichmarginalbenefitisequaltomarginalcost PracticeP237Questiontwo Solution ThevariousMeasuresofCost成本的各种衡量指标Somecostsvarywithoutput whilesomeremainthesamenomatteramountofoutputCostofproductionmaybedividedintofixedcostsandvariablecosts 成本的各种衡量 索斯蒂 特尔玛的柠檬水店THEVARIOUSMEASURESOFCOST THIRSTYTHELMA SLEMONADESTAND 索斯蒂 特尔玛的总成本曲线THIRSTYTHELMA STOTAL COSTCURVE 0 00 2 00 4 00 6 00 8 00 10 00 12 00 14 00 16 00 0 2 4 6 8 10 12 QuantityofOutput glassesoflemonadeperhour TotalCost Total costcurve 1 FixedandVariableCosts 1 Fixedcosts 固定成本 isacostthatdoesnotdependonthequantityofoutputproduced Itisthecostoffixedinput 不随着产量变动而变动的成本 即使企业不生产也要发生的成本Eg Decoration renting equipment 2 Variablecosts 可变成本 isacostthatdependsonthequantityofoutputproduced Itisthecostofthevariableinput 随着产量变动而变动的成本 企业的一些成本随着企业的变动而变动Eg RawMaterials Therefore thetotalcostofproductionequalsthefixedcost thecostofthefixedinputs plusthevariablecost thecostofthevariableinputs or TC FC VC CostCurvesforaFirm Variablecostincreaseswithproduction TotalcostistheverticalsumofFCandVC Fixedcostdoesnotvarywithoutput 讨论题 工资是否是可变成本 MarginalandAverageCostIncompletingadiscussionofcosts mustalsodistinguishbetweenAverageCostMarginalCostAfterdefinitionofcostsiscomplete onecanconsidertheanalysisbetweenshort runandlong runcosts MeasuringCosts 1 MarginalCost MC 边际成本Thecostofexpandingoutputbyoneunit Fixedcosthavenoimpactonmarginalcost soitcanbewrittenas MeasuringCosts 2 AverageTotalCost ATC AverageCost 平均总成本 CostperunitofoutputTotalcostdividedbyoutputquantityAlsoequalsaveragefixedcost AFC plusaveragevariablecost AVC 厂商在短期内平均每生产一单位产品所消耗的全部成本 2 1 Averagefixedcosts 平均固定成本 isthefixedcostperunitofoutput 固定成本除以产量FixedcostFCAFC QuantityofOutputQThelargertheoutput thegreaterthequantityofoutputoverwhichfixedcostisspread leadingtoloweraveragefixedcost 平均固定成本总是随着产量的增加而下降 2 2 Averagevariablecost 平均可变成本 isthevariablecostperunitofoutput 可变成本除以产量VariablecostVCAVC QuantityofoutputQThelargertheamount thegreatertheamountofvariableinputrequiredtoproduceadditionalunits leadingtohigheraveragevariablecost 平均可变成本总是随着产量的增加而增加 Atthelowlevelsofoutput spreadeffectdominatesthediminishingreturnseffectsandcausethetotalcostcurveslopedownward Whentheoutputislarge thediminishingreturnseffectdominatesthespreadeffect thoughthetotalcostcurveslopeupward CostCurvesforaFirm ATC MarginalCost curve Averagetotalcost curve Costcurveandtheirshapes 1 Marginalcostriseswiththeamountofoutputproduced Thisreflectsthepropertyofdiminishingmarginalproduct Costcurveandtheirshapes 2 Theaverage costcurveisU shaped Atverylowlevelsofoutputaveragetotalcostishighbecausefixedcostisspreadoveronlyafewunits Averagetotalcostdeclinesasoutputincreases Averagetotalcoststartsrisingbecauseaveragevariablecostrisessubstantially CostcurveandtheirshapesThebottomoftheU shapeoccursatthequantitythatminimizesaveragetotalcost Thisquantityissometimescalledefficientscaleofthefirm Minimum costquantity BIGBOB SCOSTCURVES 0 0 5 1 1 5 2 2 5 3 3 5 0 2 4 6 8 10 12 14 16 QuantityofOutput Costs 随着产量增加 边际成本最终要上升 平均总成本曲线是U形的 边际成本曲线与平均总成本曲线在平均总成本曲线最低点相交 RelationshipbetweenmarginalcostandAveragetotalcostWhenevermarginalcostislessthanaveragetotalcost averagetotalcostisfalling Whenevermarginalcostisgreaterthanaveragetotalcost averagetotalcostisrising Themarginalcostcurvecrossestheaveragetotalcostcurveattheefficientscale Efficientscaleisthequantitythatminimizesaveragetotalcost 假设本田公司生产4辆汽车的总成本是22 5万美元 而生产5辆汽车的总成本是25万美元 生产5辆汽车的平均总成本是多少 第五辆汽车的边际成本是多少 画一个典型企业的边际成本曲线和平均总成本曲线 并解释这两条曲线为什么相交 在什么地方相交 即问即答 SunkCost 沉没成本 isthecostthathasalreadybeenincurredandisnon recoverable Asunkcostshouldbeignoredindecisionaboutfutureactions 已经发生不可恢复的成本FirmbuysapieceofequipmentthatcannotbeconvertedtoanotheruseExpenditureontheequipmentisasunkcostHasnoalternativeusesocostcannotberecovered opportunitycostiszeroDecisiontobuytheequipmentmighthavebeengoodorbad butnowdoesnotmatter CasestudyP318EconomicsinactionWhyisthereastiffresistancefromlocalresidents Whereisthefundingoftownfrom Whereistheaveragetotalcostofservingused WhathappenedtotheMarginalcostthatisgreaterthanaveragetotalcostinthetown MeasuringCosts AllthetypesofcostsrelevanttoproductionhavenowbeendiscussedCannowdiscusshowtheydifferinthelongandshortrun Coststhatarefixedintheshortrunmaynotbefixedinthelongrun2 Typicallyinthelongrun mostifnotallcostsarevariable CostinthelongrunFormanyfirms thedivisionoftotalcostsbetweenfixedandvariablecostsdependsonthetimehorizonbeingconsidered Intheshortrunsomecostsarefixed Inthelongrunfixedcostsbecomevariablecosts becausemanycostsarefixedintheshortrunbutvariableinthelongrun afirm slongruncostcurvedifferfromitsshortruncostcurve 短期和长期的平均总成本AVERAGETOTALCOSTINTHESHORTANDLONGRUNS Quantityof CarsperDay 0 Average Total Cost FORDcompany scostcurves 1000 1200 EconomicsanddiseconomiesofscaleEconomicsofscale 规模经济 occurwhenlongrunaveragetotalcostdeclinesasoutputincreases 长期平均总成随产量增加而减少的特性Diseconomiesofscale 规模不经济 occurwhenlong runaveragetotalcostrisesasoutputincreases 长期平均总成本随产量增加而增加的特性Constantreturnofscale 规模收益不变 occurwhenlong runaveragetotalcos