微觀經(jīng)濟(jì)學(xué)成本論課件

第五章成本理論CH5TheCostTheory第五章成本理論CH5TheCostTheoryCONTENTS第一節(jié)成本的概念第二節(jié)短期成本理論第三節(jié)長期成本理論CONTENTS第一節(jié)成本的概念第一節(jié)成本的概念5-1TheConceptofCost第一節(jié)成本的概念5-1TheConceptofC一、機(jī)會(huì)成本

（opportunitycost）是指如果一定生產(chǎn)要素被用來生產(chǎn)某種產(chǎn)品，便放棄了用在其他用途上的可能獲得的收益，這筆收益就是生產(chǎn)這種產(chǎn)品的機(jī)會(huì)成本。一、機(jī)會(huì)成本

（opportunitycost）是指如果一二、顯成本與隱成本1、顯成本（explicitcost）指廠商購買生產(chǎn)要素支付貨幣所構(gòu)成的成本，是一種會(huì)計(jì)成本。2、隱成本（implicitcost）隱成本指廠商使用自有生產(chǎn)要素而支付的費(fèi)用。兩者區(qū)別:購買的生產(chǎn)要素的所有權(quán)歸誰？二、顯成本與隱成本1、顯成本（explicitcost）三、利潤（profit）總成本=顯成本+隱成本經(jīng)濟(jì)利潤=總收益—總成本，簡稱“利潤”經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別正常利潤：廠商對自己所提供的企業(yè)家才能所支付的報(bào)酬，是隱成本的一種。會(huì)計(jì)利潤=總收益—顯成本經(jīng)濟(jì)利潤=總收益—顯成本—隱成本。（不包括正常利潤）三、利潤（profit）總收益經(jīng)濟(jì)學(xué)家眼中的利潤會(huì)計(jì)師眼中的利潤經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系總收益經(jīng)濟(jì)學(xué)家會(huì)計(jì)師經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系顯性成本會(huì)計(jì)成本

(只有顯性成本)TotalRevenue經(jīng)濟(jì)學(xué)家眼中的利潤會(huì)計(jì)師眼中的利潤經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系顯性成本會(huì)計(jì)成本Total經(jīng)濟(jì)學(xué)家會(huì)計(jì)師經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的顯性成本會(huì)計(jì)成本

(只有顯性成本)會(huì)計(jì)利潤TotalRevenue經(jīng)濟(jì)學(xué)家眼中的利潤會(huì)計(jì)師眼中的利潤經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系顯性成本會(huì)計(jì)成本會(huì)計(jì)利潤Total經(jīng)濟(jì)學(xué)家會(huì)計(jì)師經(jīng)濟(jì)利潤與會(huì)隱性成本（包括正常利潤）顯性成本會(huì)計(jì)成本

(只有顯性成本)會(huì)計(jì)利潤TotalRevenue經(jīng)濟(jì)學(xué)家眼中的利潤會(huì)計(jì)師眼中的利潤經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系隱性成本顯性成本會(huì)計(jì)成本會(huì)計(jì)利潤Total經(jīng)濟(jì)學(xué)家會(huì)計(jì)師經(jīng)濟(jì)經(jīng)濟(jì)利潤隱性成本（包括正常利潤）顯性成本會(huì)計(jì)成本

(只有顯性成本)會(huì)計(jì)利潤TotalRevenue經(jīng)濟(jì)學(xué)家眼中的利潤會(huì)計(jì)師眼中的利潤經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系經(jīng)濟(jì)利潤隱性成本顯性成本會(huì)計(jì)成本會(huì)計(jì)利潤Total經(jīng)濟(jì)學(xué)家會(huì)2022/12/1712例：會(huì)計(jì)師的算法經(jīng)濟(jì)學(xué)家的算法項(xiàng)目數(shù)量項(xiàng)目數(shù)量銷售收益原材料費(fèi)用水電費(fèi)工資銀行利息300000130000100005000010000銷售收益原材料費(fèi)用水電費(fèi)工資銀行利息300000130000100005000010000隱含租金隱含利息隱含工資500001000040000會(huì)計(jì)成本200000經(jīng)濟(jì)成本300000會(huì)計(jì)利潤100000經(jīng)濟(jì)利潤02022/12/1312例：會(huì)計(jì)師的算法經(jīng)濟(jì)學(xué)家的算法項(xiàng)第二節(jié)短期成本理論5-2TheShort-runCostTheory第二節(jié)短期成本理論5-2TheShort-runC一、短期總產(chǎn)量曲線與

短期總成本曲線FromTPLtoSTC,……一、短期總產(chǎn)量曲線與

短期總成本曲線FromTPLto2022/12/17151、生產(chǎn)函數(shù)、成本函數(shù)與成本方程生產(chǎn)函數(shù)：描述的是一定技術(shù)條件下要素與最大產(chǎn)量間的技術(shù)關(guān)系。成本函數(shù)：建立在技術(shù)關(guān)系之上的成本與產(chǎn)量間的經(jīng)濟(jì)關(guān)系。成本方程：表示生產(chǎn)成本與生產(chǎn)要素的投入量之間的關(guān)系。2022/12/13151、生產(chǎn)函數(shù)、成本函數(shù)與成本方程生產(chǎn)2、短期總成本函數(shù)STC（Q）2、短期總成本函數(shù)STC（Q）2022/12/1717由短期總產(chǎn)量曲線推導(dǎo)短期總成本曲線(b)短期總成本曲線Cost500200STC(Q)

w·L(Q)

Fixedcostr·K

25050125150125(a)總產(chǎn)量曲線L100

50

2530691215150QQ2022/12/1317由短期總產(chǎn)量曲線推導(dǎo)短期總成本曲線(2022/12/1718二、短期總成本和擴(kuò)展線的關(guān)系oLＱ1Ｑ2Ｑ3A2E3K3A3A1B1B2B3K2K1L1L2L3E2E1K擴(kuò)展線短期總成本大于或者等于長期總成本擴(kuò)展線是斜率等于成本線的等斜線。2022/12/1318二、短期總成本和擴(kuò)展線的關(guān)系oLＱ1三、短期成本曲線（一）、七種短期成本1.短期總成本(TC、TFC、TVC)三、短期成本曲線（一）、七種短期成本Tobecontinued2、短期平均成本1）AC（Q）=TC/Q2）AFC（Q）=TFC/Q3）AVC（Q）=TVC/QTobecontinued2、短期平均成本Tobecontinued3.邊際成本：Tobecontinued3.邊際成本：MC=MarginalCostTFC=TotalFixedCostsTVC

=TotalVariableCostsAVC

=AverageVariableCostsTC=TotalCostsA（T）C

=AverageTotalCosts七種短期成本的縮寫形式AFC

=AverageFixedCostsMC=MarginalCostTFC=Total（二）、七種短期成本的幾何圖形CQCQTFCCQTFCTVCTCa.總不變成本曲線b.總可變成本曲線c.總成本曲線（二）、七種短期成本的幾何圖形CQCQTFCCQTFCTVCTobecontinuedCQCQCQCQAFCAVCACMCd.平均不變成本曲線

f.平均總成本曲線e.平均可變成本曲線g.邊際成本曲線TobecontinuedCQCQCQCQAFCAVCA（三）七種短期成本曲線的綜合圖平均成本等于總成本曲線上各點(diǎn)與原點(diǎn)連線的斜率；邊際成本等于總成本曲線上各點(diǎn)切線的斜率。注意“拐點(diǎn)”。（三）七種短期成本曲線的綜合圖平均成本等于總成本曲線上各點(diǎn)與2022/12/1726短期成本曲線綜合圖示COQOCQTFCAFCTVCAVCTCACMCTC與TVC都隨Q的增加而增加，兩線平行，其距離就是TFCAC與AVC的距離隨Q的增大而越來越近，其原因在于AFC的遞減。AMC相交于AVC的最低點(diǎn)。此時(shí)從原點(diǎn)出發(fā)到AVC曲線A點(diǎn)的射線與其切線重合。MC相交于AC的最低點(diǎn)。此時(shí)從原點(diǎn)出發(fā)到AC曲線B點(diǎn)的射線與其切線重合。BD與MC曲線的最低點(diǎn)D’相對應(yīng)，TC和TVC都出現(xiàn)拐點(diǎn)，從此它們上升的斜率變大。TFC與Q無關(guān)，AFC隨著Q的增加而遞減。CD’2022/12/1326短期成本曲線綜合圖示COQOCQTF綜合圖的分解之一：TC、TFC與TVC加入TFC

到TVC

意味著在總可變成本曲線上加入相同的固定成本量。所以，總成本曲線與總可變成本曲線形狀相同，只是高出一個(gè)等于總不變成本TFC的量。綜合圖的分解之一：TC、TFC與TVC加入TFC到TV綜合圖的分解之二：AC、AFC與AVC由于AFC

隨Q的增加而下降，不斷遞減的成本量加入AVC得到ATC，兩者距離隨Q的增大而越來越近。綜合圖的分解之二：AC、AFC與AVC由于AFC隨Q的增2022/12/1729綜合圖的分解之三：AC、AVC與MC如果MC低于AC、AVC，AC、AVC下降；反之則反之。MC曲線與AC、AVC曲線相交于各自的最低點(diǎn)。2022/12/1329綜合圖的分解之三：AC、AVC與MC（四）、由TC曲線到AC曲線和MC曲線平均成本等于總成本曲線上各點(diǎn)與原點(diǎn)連線的斜率；邊際成本等于總成本曲線上各點(diǎn)的切線的斜率。（四）、由TC曲線到AC曲線和MC曲線平均成本等于總成本曲線2022/12/17311、由TFC曲線推導(dǎo)AFC曲線TFCAFCAFC是TFC上的各點(diǎn)與原點(diǎn)連線的斜率值的軌跡。2022/12/13311、由TFC曲線推導(dǎo)AFC曲線TFC2022/12/17322、由TVC曲線推導(dǎo)AVC曲線AVC是TVC線上各點(diǎn)與原點(diǎn)連線的斜率值的軌跡。A點(diǎn)是AVC的最低點(diǎn)。ACQTVCAVC2022/12/13322、由TVC曲線推導(dǎo)AVC曲線AVC3、由TC曲線推導(dǎo)AC曲線AC是TC曲線上的點(diǎn)與原點(diǎn)連線斜率值的軌跡。B點(diǎn)是AC的最低點(diǎn)。ABCQTCACO3、由TC曲線推導(dǎo)AC曲線AC是TC曲線上ABCQTCACO2022/12/17344、AVC和AC最低點(diǎn)的比較因?yàn)門VC的射線與切線重合點(diǎn)在TC之前出現(xiàn)，所以

AVC的最低點(diǎn)在AC之前。AVCACTCTVC2022/12/13344、AVC和AC最低點(diǎn)的比較因?yàn)門V5、由TC或者TVC曲線推導(dǎo)MC

曲線MC是TVC（TC）曲線對應(yīng)點(diǎn)導(dǎo)數(shù)的軌跡；B點(diǎn)是一重要拐點(diǎn)，它是TVC曲線斜率最小之處，對應(yīng)B’點(diǎn)。CQTVCMCBB’0拐點(diǎn)B處一階導(dǎo)數(shù)最小，且二階導(dǎo)數(shù)為零。5、由TC或者TVC曲線推導(dǎo)MC曲線MC是TVC（TC）比較:MC曲線與AC、AVC曲線MC曲線先到達(dá)最低點(diǎn)；MC分別與AVC或AC曲線在各自最低處相交。QCMCACAVC比較:MC曲線與AC、AVC曲線MC曲線先到達(dá)最低點(diǎn)；QCMMarginalCost=MC

TotalFixedCosts=TFCTotalVariableCosts=TVCAverageVariableCosts=AVCTotalCosts=TC

AverageTotalCosts=ATCAverageFixedCosts=AFCSummaryofDefinitions...MarginalCost=MCTotalFixQuantityCosts(dollars)CostsGraphicallyPresented...QuantityCosts(dollars)CostsGQuantityCosts(dollars)TVCVariableCostCostsGraphicallyPresented...QuantityCosts(dollars)TVCVariQuantityCosts(dollars)TFCCostsGraphicallyPresented...QuantityCosts(dollars)TFCCostQuantityCosts(dollars)TFCCombiningwithvariablecost...CostsGraphicallyPresented...QuantityCosts(dollars)TFCCombQuantityCosts(dollars)CostsGraphicallyPresented...TVCVariableCostQuantityCosts(dollars)CostsGQuantityCosts(dollars)AddverticallytogetTotalCostCostsGraphicallyPresented...TFCTVCVariableCostQuantityCosts(dollars)AddverQuantityCosts(dollars)TCTotalCostFixedCostCostsGraphicallyPresented...TVCVariableCostTFCQuantityCosts(dollars)TCTotalQuantityShort-runaveragecosts(dollars)PlottingAverageCostsCostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCCostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCAVCCostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCAVCAddverticallytoget...CostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCAVCATCCostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCAVCATCPlottingthechangesintotalcostyields...CostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCAVCATCMCCostsGraphicallyPresented...QuantityShort-runaveragecost2022/12/1752（五）、短期成本變動(dòng)的決定因素：

邊際報(bào)酬遞減規(guī)律回顧：邊際報(bào)酬遞減規(guī)律MPL先升后降2022/12/1352（五）、短期成本變動(dòng)的決定因素：

邊2022/12/1753TotalProduct,TPQuantityofLaborAverageProduct,AP,andmarginalproduct,MPQuantityofLabor再瀏覽一遍：LawofDiminishingReturnsMarginalProductAverageProductTotalOutputIncreasingMarginalReturns2022/12/1353TotalProduct,TPQ2022/12/1754TotalProduct,TPQuantityofLaborAverageProduct,AP,andmarginalproduct,MPQuantityofLaborLawofDiminishingReturnsDiminishingMarginalReturnsMarginalProductAverageProductTotalOutput2022/12/1354TotalProduct,TPQ2022/12/1755TotalProduct,TPQuantityofLaborAverageProduct,AP,andmarginalproduct,MPQuantityofLaborTotalOutputMarginalProductAverageProductNegativeMarginalReturnsLawofDiminishingReturns2022/12/1355TotalProduct,TPQ2022/12/1756MPL與MC的關(guān)系在短期生產(chǎn)中，MPL遞增階段對應(yīng)MC遞減階段；MPL遞減階段對應(yīng)MC遞增階段；MPL最大值對應(yīng)MC最小值。2022/12/1356MPL與MC的關(guān)系在短期生產(chǎn)中，M2022/12/1757MPL與MC的關(guān)系圖示2022/12/1357MPL與MC的關(guān)系圖示QuantityoflaborCosts(dollars)AverageproductandmarginalproductQuantityofoutputProductivity&CostCurveRelationshipQuantityoflaborCosts(dollarQuantityoflaborCosts(dollars)AverageproductandmarginalproductQuantityofoutputMPMCProductivity&CostCurveRelationshipQuantityoflaborCosts(dollarQuantityoflaborCosts(dollars)AverageproductandmarginalproductQuantityofoutputMPAPMCAVCProductivity&CostCurveRelationshipQuantityoflaborCosts(dollar（六）短期產(chǎn)量曲線與短期成本曲線之間的關(guān)系短期生產(chǎn)函數(shù)短期成本函數(shù)為（六）短期產(chǎn)量曲線與短期成本曲線之間的關(guān)系短期生產(chǎn)函數(shù)1、邊際產(chǎn)量和邊際成本246MPL0

4

10369MCCQL根據(jù)邊際成本定義，得：1、邊際產(chǎn)量和邊際成本246MPL0 4 2022/12/1763QuantityofoutputMPMC邊際產(chǎn)量曲線與邊際成本曲線之間的關(guān)系QC00LQ邊際報(bào)酬遞減規(guī)律決定了曲線的形狀！APAVC2022/12/1363Quantityofoutput2、、平均產(chǎn)量和平均可變成本Labor246MPAPLabor0

4

10369MCAVCCACQ2、、平均產(chǎn)量和平均可變成本Labor246MPAPLaboTFC短期生產(chǎn)函數(shù)和短期成本函數(shù)之間的對應(yīng)關(guān)系QL0TPL·

QLMPLAPLQCACAVCCQTCTVC0(a)(b)(c)(d)MCTFC短期生產(chǎn)函數(shù)和短期成本函數(shù)之間的對應(yīng)關(guān)系QL0TPL·邊際成本處于上升階段，平均可變成本也越過最低點(diǎn)，處于遞增狀態(tài)TFC短期生產(chǎn)函數(shù)和短期成本函數(shù)之間的對應(yīng)關(guān)系QL0TPL·

QLMPLAPLQCACAVCCQTCTVC0(a)(b)(c)(d)MC第二階段：經(jīng)濟(jì)區(qū)域邊際成本處于上升階段，平均可變成本也越過最低點(diǎn)，處于遞增狀態(tài)2022/12/1767MarginalCost=MC

TotalFixedCosts=TFCTotalVariableCosts=TVCAverageVariableCosts=AVCTotalCosts=TC

AverageTotalCosts=ATCAverageFixedCosts=AFCSummaryofDefinitions...2022/12/1367MarginalCost=M2022/12/1768QuantityCosts(dollars)CostsGraphicallyPresented...2022/12/1368QuantityCosts(dol2022/12/1769QuantityCosts(dollars)TVCVariableCostCostsGraphicallyPresented...2022/12/1369QuantityCosts(dol2022/12/1770QuantityCosts(dollars)TFCCostsGraphicallyPresented...2022/12/1370QuantityCosts(dol2022/12/1771QuantityCosts(dollars)TFCCombiningwithvariablecost...CostsGraphicallyPresented...2022/12/1371QuantityCosts(dol2022/12/1772QuantityCosts(dollars)CostsGraphicallyPresented...TVCVariableCost2022/12/1372QuantityCosts(dol2022/12/1773QuantityCosts(dollars)AddverticallytogetTotalCostCostsGraphicallyPresented...TFCTVCVariableCost2022/12/1373QuantityCosts(dol2022/12/1774QuantityCosts(dollars)TCTotalCostFixedCostCostsGraphicallyPresented...TVCVariableCostTFC2022/12/1374QuantityCosts(dol2022/12/1775QuantityShort-runaveragecosts(dollars)PlottingAverageCostsCostsGraphicallyPresented...2022/12/1375QuantityShort-run2022/12/1776QuantityShort-runaveragecosts(dollars)AFCCostsGraphicallyPresented...2022/12/1376QuantityShort-run2022/12/1777QuantityShort-runaveragecosts(dollars)AFCAVCCostsGraphicallyPresented...2022/12/1377QuantityShort-run2022/12/1778QuantityShort-runaveragecosts(dollars)AFCAVCAddverticallytoget...CostsGraphicallyPresented...2022/12/1378QuantityShort-run2022/12/1779QuantityShort-runaveragecosts(dollars)AFCAVCATCCostsGraphicallyPresented...2022/12/1379QuantityShort-run2022/12/1780QuantityShort-runaveragecosts(dollars)AFCAVCATCPlottingthechangesintotalcostyields...CostsGraphicallyPresented...2022/12/1380QuantityShort-run2022/12/1781QuantityShort-runaveragecosts(dollars)AFCAVCATCMCCostsGraphicallyPresented...2022/12/1381QuantityShort-run第三節(jié)長期成本理論5-3TheLong-runCostTheory第三節(jié)長期成本理論5-3TheLong-runCo2022/12/1783Long-runorShort-runCost？2022/12/1383Long-runorShort-2022/12/1784LTC曲線、LAC曲線和LMC曲線總成本平均成本邊際成本產(chǎn)量產(chǎn)量（a）（b）0LACLMCLTC2022/12/1384LTC曲線、LAC曲線和LMC曲線總一、LTC函數(shù)和LTC曲線由長期生產(chǎn)函數(shù)和成本方程，得一、LTC函數(shù)和LTC曲線由長期生產(chǎn)函數(shù)和成本方程，最優(yōu)生產(chǎn)規(guī)模選擇和LTC曲線每條STC曲線代表一種生產(chǎn)規(guī)模。a、b、c是STC曲線與LTC曲線的切點(diǎn)，表示不同產(chǎn)量下的最低總成本。STC1STC2STC3LTC0QCdebacQ1Q2Q3最優(yōu)生產(chǎn)規(guī)模選擇和LTC曲線每條STC曲線代表一種生產(chǎn)規(guī)模。2022/12/1787LTC曲線LTC線是STC線的包絡(luò)線。包絡(luò)線（envelope-curve）是指LTC線把無數(shù)條STC線包圍起來的連線。在包絡(luò)線上，每一條STC線與LTC線不相交但相切。2022/12/1387LTC曲線LTC線是STC線的包絡(luò)線擴(kuò)展線和LTC曲線oA2A3A1KB1B2B3Low·OB3=r·OA3C50100150QE3E2E1擴(kuò)展線Ｑ1=50Ｑ3=150Ｑ2=100RLTCw·OB2=r·OA2w·OB1=r·OA1擴(kuò)展線和LTC曲線oA2A3A1KB1B2B3Low·OB32022/12/1789REVIEW：擴(kuò)展線和STCoLＱ1Ｑ2Ｑ3A2E3K3A3A1B1B2B3K2K1L1L2L3E2E1K擴(kuò)展線STC≥LTC擴(kuò)展線是斜率等于成本線的等斜線。2022/12/1389REVIEW：擴(kuò)展線和STCoLＱ1二、長期平均成本二、長期平均成本2022/12/1791LAC曲線的推導(dǎo)（一）LTC曲線上各點(diǎn)與原點(diǎn)的連線的斜率值，即為LAC曲線。00CCQQLTCLACBAA’B’CC’2022/12/1391LAC曲線的推導(dǎo)（一）LTC曲線上各LAC曲線的推導(dǎo)（二）LAC曲線是無數(shù)條SAC曲線的包絡(luò)線。0QCSAC1SAC2SAC3C1Q1Q2Q1’C2Q2’C3Q3LAC曲線的推導(dǎo)（二）0QCSAC1SAC2SAC3C1Q1CostsOutputForeveryplantcapacitysize...thereisashort-runACcurve

andeveryAChasaminimumcost每條SAC曲線代表一種規(guī)模的生產(chǎn)平均成本CostsOutputForeveryplantcapCOutputAninfinitenumberofsuchcostcurvescanbeconstructed...無數(shù)不同規(guī)模的SAC曲線COutputAninfinitenumberofsLAC與SAC最低點(diǎn)的右邊相切LAC與SAC最低點(diǎn)的左邊相切TheLong-runACjust“envelopes”alloftheshort-runACcurvesCOutput形成LAC曲線LAC曲線是SAC曲線的包絡(luò)線：SAC曲線與LAC曲線切點(diǎn)的連線。注意：LAC曲線不一定是SAC曲線的最低點(diǎn)連線。LAC與SAC最低點(diǎn)的右邊相切LAC與SAC最低點(diǎn)的左邊相切LACOutput分析LAC曲線的形狀CLAC曲線是條“U”型曲線，表示在企業(yè)生產(chǎn)擴(kuò)張的開始階段，由于擴(kuò)大生產(chǎn)規(guī)模而使經(jīng)濟(jì)效益得到提高，此為規(guī)模經(jīng)濟(jì)（內(nèi)在經(jīng)濟(jì)）；然后，隨著企業(yè)規(guī)模的擴(kuò)大，經(jīng)濟(jì)效益下降，此為規(guī)模不經(jīng)濟(jì)（內(nèi)在不經(jīng)濟(jì)）。規(guī)模經(jīng)濟(jì)規(guī)模不經(jīng)濟(jì)LACOutput分析LAC曲線的形狀CLAC曲線是條“U”2022/12/1797規(guī)模經(jīng)濟(jì)（economiesofScale）的原因

不可分性投入成本的分?jǐn)偼度氲膶I(yè)化2022/12/1397規(guī)模經(jīng)濟(jì)（economiesof2022/12/1798不可分性投入成本的分?jǐn)傄粋€(gè)計(jì)算機(jī)芯片公司中的無菌車間、精密儀器和檢驗(yàn)設(shè)備；船商橫渡大西洋，將電視機(jī)從日本運(yùn)往美國所使用的大型輪船；比薩餅店使用的烤爐；有線電視公司在其領(lǐng)域內(nèi)鋪設(shè)的電纜；嚇跑海獅的假食人鯨模具。2022/12/1398不可分性投入成本的分?jǐn)傄粋€(gè)計(jì)算機(jī)芯片2022/12/1799投入的專業(yè)化分工提高效率（亞當(dāng)．斯密）AdamSmith，TheWealthofNations（NewYork：TheModernLibrary，1937），pp.4-5.2022/12/1399投入的專業(yè)化分工提高效率（亞當(dāng)．斯密2022/12/17100規(guī)模不經(jīng)濟(jì)（DiseconomiesofScale）的原因協(xié)調(diào)問題遞增的投入成本2022/12/13100規(guī)模不經(jīng)濟(jì)（Diseconomie2022/12/17101Q0CLAC2LAC1LAC位置平行下降，是外在經(jīng)濟(jì)的表現(xiàn)。LAC曲線的移動(dòng)：外在經(jīng)濟(jì)和外在不經(jīng)濟(jì)2022/12/13101Q0CLAC2LAC1LAC位置平2022/12/17102Q0CLAC1LAC2LAC位置平行下降，是外在不經(jīng)濟(jì)的表現(xiàn)。LAC曲線的移動(dòng)：外在經(jīng)濟(jì)和外在不經(jīng)濟(jì)2022/12/13102Q0CLAC1LAC2LAC位置平2022/12/17103規(guī)模報(bào)酬與規(guī)模經(jīng)濟(jì)的關(guān)系規(guī)模報(bào)酬分析是特例分析。各要素投入比例保持不變。2022/12/13103規(guī)模報(bào)酬與規(guī)模經(jīng)濟(jì)的關(guān)系規(guī)模報(bào)酬分2022/12/17104ReviewChapter4：規(guī)模報(bào)酬

規(guī)模報(bào)酬變化：在其他條件不變的情況下，企業(yè)內(nèi)部各種生產(chǎn)要素按相同比例變化時(shí)所帶來的產(chǎn)量變化。1) 規(guī)模報(bào)酬遞增2) 規(guī)模報(bào)酬不變3) 規(guī)模報(bào)酬遞減2022/12/13104ReviewChapter4：2022/12/17105ReviewChapter4:規(guī)模報(bào)酬遞增LK102030510240A2022/12/13105ReviewChapter4:2022/12/17106ReviewChapter4:規(guī)模報(bào)酬遞減LK102030510240A2022/12/13106ReviewChapter4:2022/12/17107ReviewChapter4:規(guī)模報(bào)酬不變LK10203015510240A62022/12/13107ReviewChapter4:2022/12/17108柯布-道格拉斯生產(chǎn)函數(shù)ProductionFunctionofCobb-DouglasQ=ALαKβReviewChapter4:2022/12/13108柯布-道格拉斯生產(chǎn)函數(shù)Produc2022/12/17109ProductionFunctionofCobb-DouglasA代表技術(shù)水平,0<、<1。如果+>1，規(guī)模報(bào)酬遞增；+=1，規(guī)模報(bào)酬不變；+<1則規(guī)模報(bào)酬遞減。2022/12/13109ProductionFuncti2022/12/17110三、長期邊際成本2022/12/13110三、長期邊際成本2022/12/17111LMC曲線的推導(dǎo)（一）LTC曲線上各點(diǎn)切線的斜率值，即為LMC曲線。00CCQQLTCLMCBAA”B’CC”D’D2022/12/13111LMC曲線的推導(dǎo)（一）LTC曲線上LMC曲線的推導(dǎo)（二）CQ0LACSAC1SMC1Q1SAC2SMC2SAC3SMC3·PRSLMCQ2Q3LMC曲線不是SMC曲線的包絡(luò)線。LMC與SMC1

相交；SMC1和SAC1相交，代表某一最優(yōu)生產(chǎn)規(guī)模。a點(diǎn)是SAC1與LAC相切之處，P點(diǎn)與a點(diǎn)對應(yīng)，產(chǎn)量水平為Q1。aLMC曲線的推導(dǎo)（二）CQ0LACSAC1SMC1Q1SAC2022/12/17113LMC曲線是一條“U”型曲線。LMC曲線與LAC曲線相交于LAC曲線的最低點(diǎn)。LMC曲線的形狀0CQLACBLMCA規(guī)模經(jīng)濟(jì)規(guī)模不經(jīng)濟(jì)LMC<LACLMC>LAC2022/12/13113LMC曲線是一條“U”型曲線。LM2022/12/17114LTC曲線、LAC曲線和LMC曲線總成本平均成本邊際成本產(chǎn)量產(chǎn)量（a）（b）0LACLMCLTC2022/12/13114LTC曲線、LAC曲線和LMC曲線演講完畢，謝謝觀看！演講完畢，謝謝觀看！第五章成本理論CH5TheCostTheory第五章成本理論CH5TheCostTheoryCONTENTS第一節(jié)成本的概念第二節(jié)短期成本理論第三節(jié)長期成本理論CONTENTS第一節(jié)成本的概念第一節(jié)成本的概念5-1TheConceptofCost第一節(jié)成本的概念5-1TheConceptofC一、機(jī)會(huì)成本

（opportunitycost）是指如果一定生產(chǎn)要素被用來生產(chǎn)某種產(chǎn)品，便放棄了用在其他用途上的可能獲得的收益，這筆收益就是生產(chǎn)這種產(chǎn)品的機(jī)會(huì)成本。一、機(jī)會(huì)成本

（opportunitycost）是指如果一二、顯成本與隱成本1、顯成本（explicitcost）指廠商購買生產(chǎn)要素支付貨幣所構(gòu)成的成本，是一種會(huì)計(jì)成本。2、隱成本（implicitcost）隱成本指廠商使用自有生產(chǎn)要素而支付的費(fèi)用。兩者區(qū)別:購買的生產(chǎn)要素的所有權(quán)歸誰？二、顯成本與隱成本1、顯成本（explicitcost）三、利潤（profit）總成本=顯成本+隱成本經(jīng)濟(jì)利潤=總收益—總成本，簡稱“利潤”經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別正常利潤：廠商對自己所提供的企業(yè)家才能所支付的報(bào)酬，是隱成本的一種。會(huì)計(jì)利潤=總收益—顯成本經(jīng)濟(jì)利潤=總收益—顯成本—隱成本。（不包括正常利潤）三、利潤（profit）總收益經(jīng)濟(jì)學(xué)家眼中的利潤會(huì)計(jì)師眼中的利潤經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系總收益經(jīng)濟(jì)學(xué)家會(huì)計(jì)師經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系顯性成本會(huì)計(jì)成本

(只有顯性成本)TotalRevenue經(jīng)濟(jì)學(xué)家眼中的利潤會(huì)計(jì)師眼中的利潤經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系顯性成本會(huì)計(jì)成本Total經(jīng)濟(jì)學(xué)家會(huì)計(jì)師經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的顯性成本會(huì)計(jì)成本

(只有顯性成本)會(huì)計(jì)利潤TotalRevenue經(jīng)濟(jì)學(xué)家眼中的利潤會(huì)計(jì)師眼中的利潤經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系顯性成本會(huì)計(jì)成本會(huì)計(jì)利潤Total經(jīng)濟(jì)學(xué)家會(huì)計(jì)師經(jīng)濟(jì)利潤與會(huì)隱性成本（包括正常利潤）顯性成本會(huì)計(jì)成本

(只有顯性成本)會(huì)計(jì)利潤TotalRevenue經(jīng)濟(jì)學(xué)家眼中的利潤會(huì)計(jì)師眼中的利潤經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系隱性成本顯性成本會(huì)計(jì)成本會(huì)計(jì)利潤Total經(jīng)濟(jì)學(xué)家會(huì)計(jì)師經(jīng)濟(jì)經(jīng)濟(jì)利潤隱性成本（包括正常利潤）顯性成本會(huì)計(jì)成本

(只有顯性成本)會(huì)計(jì)利潤TotalRevenue經(jīng)濟(jì)學(xué)家眼中的利潤會(huì)計(jì)師眼中的利潤經(jīng)濟(jì)利潤與會(huì)計(jì)利潤的區(qū)別與聯(lián)系經(jīng)濟(jì)利潤隱性成本顯性成本會(huì)計(jì)成本會(huì)計(jì)利潤Total經(jīng)濟(jì)學(xué)家會(huì)2022/12/17127例：會(huì)計(jì)師的算法經(jīng)濟(jì)學(xué)家的算法項(xiàng)目數(shù)量項(xiàng)目數(shù)量銷售收益原材料費(fèi)用水電費(fèi)工資銀行利息300000130000100005000010000銷售收益原材料費(fèi)用水電費(fèi)工資銀行利息300000130000100005000010000隱含租金隱含利息隱含工資500001000040000會(huì)計(jì)成本200000經(jīng)濟(jì)成本300000會(huì)計(jì)利潤100000經(jīng)濟(jì)利潤02022/12/1312例：會(huì)計(jì)師的算法經(jīng)濟(jì)學(xué)家的算法項(xiàng)第二節(jié)短期成本理論5-2TheShort-runCostTheory第二節(jié)短期成本理論5-2TheShort-runC一、短期總產(chǎn)量曲線與

短期總成本曲線FromTPLtoSTC,……一、短期總產(chǎn)量曲線與

短期總成本曲線FromTPLto2022/12/171301、生產(chǎn)函數(shù)、成本函數(shù)與成本方程生產(chǎn)函數(shù)：描述的是一定技術(shù)條件下要素與最大產(chǎn)量間的技術(shù)關(guān)系。成本函數(shù)：建立在技術(shù)關(guān)系之上的成本與產(chǎn)量間的經(jīng)濟(jì)關(guān)系。成本方程：表示生產(chǎn)成本與生產(chǎn)要素的投入量之間的關(guān)系。2022/12/13151、生產(chǎn)函數(shù)、成本函數(shù)與成本方程生產(chǎn)2、短期總成本函數(shù)STC（Q）2、短期總成本函數(shù)STC（Q）2022/12/17132由短期總產(chǎn)量曲線推導(dǎo)短期總成本曲線(b)短期總成本曲線Cost500200STC(Q)

w·L(Q)

Fixedcostr·K

25050125150125(a)總產(chǎn)量曲線L100

50

2530691215150QQ2022/12/1317由短期總產(chǎn)量曲線推導(dǎo)短期總成本曲線(2022/12/17133二、短期總成本和擴(kuò)展線的關(guān)系oLＱ1Ｑ2Ｑ3A2E3K3A3A1B1B2B3K2K1L1L2L3E2E1K擴(kuò)展線短期總成本大于或者等于長期總成本擴(kuò)展線是斜率等于成本線的等斜線。2022/12/1318二、短期總成本和擴(kuò)展線的關(guān)系oLＱ1三、短期成本曲線（一）、七種短期成本1.短期總成本(TC、TFC、TVC)三、短期成本曲線（一）、七種短期成本Tobecontinued2、短期平均成本1）AC（Q）=TC/Q2）AFC（Q）=TFC/Q3）AVC（Q）=TVC/QTobecontinued2、短期平均成本Tobecontinued3.邊際成本：Tobecontinued3.邊際成本：MC=MarginalCostTFC=TotalFixedCostsTVC

=TotalVariableCostsAVC

=AverageVariableCostsTC=TotalCostsA（T）C

=AverageTotalCosts七種短期成本的縮寫形式AFC

=AverageFixedCostsMC=MarginalCostTFC=Total（二）、七種短期成本的幾何圖形CQCQTFCCQTFCTVCTCa.總不變成本曲線b.總可變成本曲線c.總成本曲線（二）、七種短期成本的幾何圖形CQCQTFCCQTFCTVCTobecontinuedCQCQCQCQAFCAVCACMCd.平均不變成本曲線

f.平均總成本曲線e.平均可變成本曲線g.邊際成本曲線TobecontinuedCQCQCQCQAFCAVCA（三）七種短期成本曲線的綜合圖平均成本等于總成本曲線上各點(diǎn)與原點(diǎn)連線的斜率；邊際成本等于總成本曲線上各點(diǎn)切線的斜率。注意“拐點(diǎn)”。（三）七種短期成本曲線的綜合圖平均成本等于總成本曲線上各點(diǎn)與2022/12/17141短期成本曲線綜合圖示COQOCQTFCAFCTVCAVCTCACMCTC與TVC都隨Q的增加而增加，兩線平行，其距離就是TFCAC與AVC的距離隨Q的增大而越來越近，其原因在于AFC的遞減。AMC相交于AVC的最低點(diǎn)。此時(shí)從原點(diǎn)出發(fā)到AVC曲線A點(diǎn)的射線與其切線重合。MC相交于AC的最低點(diǎn)。此時(shí)從原點(diǎn)出發(fā)到AC曲線B點(diǎn)的射線與其切線重合。BD與MC曲線的最低點(diǎn)D’相對應(yīng)，TC和TVC都出現(xiàn)拐點(diǎn)，從此它們上升的斜率變大。TFC與Q無關(guān)，AFC隨著Q的增加而遞減。CD’2022/12/1326短期成本曲線綜合圖示COQOCQTF綜合圖的分解之一：TC、TFC與TVC加入TFC

到TVC

意味著在總可變成本曲線上加入相同的固定成本量。所以，總成本曲線與總可變成本曲線形狀相同，只是高出一個(gè)等于總不變成本TFC的量。綜合圖的分解之一：TC、TFC與TVC加入TFC到TV綜合圖的分解之二：AC、AFC與AVC由于AFC

隨Q的增加而下降，不斷遞減的成本量加入AVC得到ATC，兩者距離隨Q的增大而越來越近。綜合圖的分解之二：AC、AFC與AVC由于AFC隨Q的增2022/12/17144綜合圖的分解之三：AC、AVC與MC如果MC低于AC、AVC，AC、AVC下降；反之則反之。MC曲線與AC、AVC曲線相交于各自的最低點(diǎn)。2022/12/1329綜合圖的分解之三：AC、AVC與MC（四）、由TC曲線到AC曲線和MC曲線平均成本等于總成本曲線上各點(diǎn)與原點(diǎn)連線的斜率；邊際成本等于總成本曲線上各點(diǎn)的切線的斜率。（四）、由TC曲線到AC曲線和MC曲線平均成本等于總成本曲線2022/12/171461、由TFC曲線推導(dǎo)AFC曲線TFCAFCAFC是TFC上的各點(diǎn)與原點(diǎn)連線的斜率值的軌跡。2022/12/13311、由TFC曲線推導(dǎo)AFC曲線TFC2022/12/171472、由TVC曲線推導(dǎo)AVC曲線AVC是TVC線上各點(diǎn)與原點(diǎn)連線的斜率值的軌跡。A點(diǎn)是AVC的最低點(diǎn)。ACQTVCAVC2022/12/13322、由TVC曲線推導(dǎo)AVC曲線AVC3、由TC曲線推導(dǎo)AC曲線AC是TC曲線上的點(diǎn)與原點(diǎn)連線斜率值的軌跡。B點(diǎn)是AC的最低點(diǎn)。ABCQTCACO3、由TC曲線推導(dǎo)AC曲線AC是TC曲線上ABCQTCACO2022/12/171494、AVC和AC最低點(diǎn)的比較因?yàn)門VC的射線與切線重合點(diǎn)在TC之前出現(xiàn)，所以

AVC的最低點(diǎn)在AC之前。AVCACTCTVC2022/12/13344、AVC和AC最低點(diǎn)的比較因?yàn)門V5、由TC或者TVC曲線推導(dǎo)MC

曲線MC是TVC（TC）曲線對應(yīng)點(diǎn)導(dǎo)數(shù)的軌跡；B點(diǎn)是一重要拐點(diǎn)，它是TVC曲線斜率最小之處，對應(yīng)B’點(diǎn)。CQTVCMCBB’0拐點(diǎn)B處一階導(dǎo)數(shù)最小，且二階導(dǎo)數(shù)為零。5、由TC或者TVC曲線推導(dǎo)MC曲線MC是TVC（TC）比較:MC曲線與AC、AVC曲線MC曲線先到達(dá)最低點(diǎn)；MC分別與AVC或AC曲線在各自最低處相交。QCMCACAVC比較:MC曲線與AC、AVC曲線MC曲線先到達(dá)最低點(diǎn)；QCMMarginalCost=MC

TotalFixedCosts=TFCTotalVariableCosts=TVCAverageVariableCosts=AVCTotalCosts=TC

AverageTotalCosts=ATCAverageFixedCosts=AFCSummaryofDefinitions...MarginalCost=MCTotalFixQuantityCosts(dollars)CostsGraphicallyPresented...QuantityCosts(dollars)CostsGQuantityCosts(dollars)TVCVariableCostCostsGraphicallyPresented...QuantityCosts(dollars)TVCVariQuantityCosts(dollars)TFCCostsGraphicallyPresented...QuantityCosts(dollars)TFCCostQuantityCosts(dollars)TFCCombiningwithvariablecost...CostsGraphicallyPresented...QuantityCosts(dollars)TFCCombQuantityCosts(dollars)CostsGraphicallyPresented...TVCVariableCostQuantityCosts(dollars)CostsGQuantityCosts(dollars)AddverticallytogetTotalCostCostsGraphicallyPresented...TFCTVCVariableCostQuantityCosts(dollars)AddverQuantityCosts(dollars)TCTotalCostFixedCostCostsGraphicallyPresented...TVCVariableCostTFCQuantityCosts(dollars)TCTotalQuantityShort-runaveragecosts(dollars)PlottingAverageCostsCostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCCostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCAVCCostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCAVCAddverticallytoget...CostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCAVCATCCostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCAVCATCPlottingthechangesintotalcostyields...CostsGraphicallyPresented...QuantityShort-runaveragecostQuantityShort-runaveragecosts(dollars)AFCAVCATCMCCostsGraphicallyPresented...QuantityShort-runaveragecost2022/12/17167（五）、短期成本變動(dòng)的決定因素：

邊際報(bào)酬遞減規(guī)律回顧：邊際報(bào)酬遞減規(guī)律MPL先升后降2022/12/1352（五）、短期成本變動(dòng)的決定因素：

邊2022/12/17168TotalProduct,TPQuantityofLaborAverageProduct,AP,andmarginalproduct,MPQuantityofLabor再瀏覽一遍：LawofDiminishingReturnsMarginalProductAverageProductTotalOutputIncreasingMarginalReturns2022/12/1353TotalProduct,TPQ2022/12/17169TotalProduct,TPQuantityofLaborAverageProduct,AP,andmarginalproduct,MPQuantityofLaborLawofDiminishingReturnsDiminishingMarginalReturnsMarginalProductAverageProductTotalOutput2022/12/1354TotalProduct,TPQ2022/12/17170TotalProduct,TPQuantityofLaborAverageProduct,AP,andmarginalproduct,MPQuantityofLaborTotalOutputMarginalProductAverageProductNegativeMarginalReturnsLawofDiminishingReturns2022/12/1355TotalProduct,TPQ2022/12/17171MPL與MC的關(guān)系在短期生產(chǎn)中，MPL遞增階段對應(yīng)MC遞減階段；MPL遞減階段對應(yīng)MC遞增階段；MPL最大值對應(yīng)MC最小值。2022/12/1356MPL與MC的關(guān)系在短期生產(chǎn)中，M2022/12/17172MPL與MC的關(guān)系圖示2022/12/1357MPL與MC的關(guān)系圖示QuantityoflaborCosts(dollars)AverageproductandmarginalproductQuantityofoutputProductivity&CostCurveRelationshipQuantityoflaborCosts(dollarQuantityoflaborCosts(dollars)AverageproductandmarginalproductQuantityofoutputMPMCProductivity&CostCurveRelationshipQuantityoflaborCosts(dollarQuantityoflaborCosts(dollars)AverageproductandmarginalproductQuantityofoutputMPAPMCAVCProductivity&CostCurveRelationshipQuantityoflaborCosts(dollar（六）短期產(chǎn)量曲線與短期成本曲線之間的關(guān)系短期生產(chǎn)函數(shù)短期成本函數(shù)為（六）短期產(chǎn)量曲線與短期成本曲線之間的關(guān)系短期生產(chǎn)函數(shù)1、邊際產(chǎn)量和邊際成本246MPL0

4

10369MCCQL根據(jù)邊際成本定義，得：1、邊際產(chǎn)量和邊際成本246MPL0 4 2022/12/17178QuantityofoutputMPMC邊際產(chǎn)量曲線與邊際成本曲線之間的關(guān)系QC00LQ邊際報(bào)酬遞減規(guī)律決定了曲線的形狀！APAVC2022/12/1363Quantityofoutput2、、平均產(chǎn)量和平均可變成本Labor246MPAPLabor0

4

10369MCAVCCACQ2、、平均產(chǎn)量和平均可變成本Labor246MPAPLaboTFC短期生產(chǎn)函數(shù)和短期成本函數(shù)之間的對應(yīng)關(guān)系QL0TPL·

QLMPLAPLQCACAVCCQTCTVC0(a)(b)(c)(d)MCTFC短期生產(chǎn)函數(shù)和短期成本函數(shù)之間的對應(yīng)關(guān)系QL0TPL·邊際成本處于上升階段，平均可變成本也越過最低點(diǎn)，處于遞增狀態(tài)TFC短期生產(chǎn)函數(shù)和短期成本函數(shù)之間的對應(yīng)關(guān)系QL0TPL·

QLMPLAPLQCACAVCCQTCTVC0(a)(b)(c)(d)MC第二階段：經(jīng)濟(jì)區(qū)域邊際成本處于上升階段，平均可變成本也越過最低點(diǎn)，處于遞增狀態(tài)2022/12/17182MarginalCost=MC

TotalFixedCosts=TFCTotalVariableCosts=TVCAverageVariableCosts=AVCTotalCosts=TC

AverageTotalCosts=ATCAverageFixedCosts=AFCSummaryofDefinitions...2022/12/1367MarginalCost=M2022/12/17183QuantityCosts(dollars)CostsGraphicallyPresented...2022/12/1368QuantityCosts(dol2022/12/17184QuantityCosts(dollars)TVCVariableCostCostsGraphicallyPresented...2022/12/1369QuantityCosts(dol2022/12/17185QuantityCosts(dollars)TFCCostsGraphicallyPresented...2022/12/1370QuantityCosts(dol2022/12/17186QuantityCosts(dollars)TFCCombiningwithvariablecost...CostsGraphicallyPresented...2022/12/1371QuantityCosts(dol2022/12/17187QuantityCosts(dollars)CostsGraphicallyPresented...TVCVariableCost2022/12/1372QuantityCosts(dol2022/12/17188QuantityCosts(dollars)AddverticallytogetTotalCostCostsGraphicallyPresented...TFCTVCVariableCost2022/12/1373QuantityCosts(dol2022/12/17189QuantityCosts(dollars)TCTotalCostFixedCostCostsGraphicallyPresented...TVCVariableCostTFC2022/12/1374QuantityCosts(dol2022/12/17190QuantityShort-runaveragecosts(dollars)PlottingAverageCostsCostsGraphicallyPresented...2022/12/1375QuantityShort-run2022/12/17191QuantityShort-runaveragecosts(dollars)AFCCostsGraphicallyPresented...2022/12/1376QuantityShort-run2022/12/17192QuantityShort-runaveragecosts(dollars)AFCAVCCostsGraphicallyPresented...2022/12/1377QuantityShort-run2022/12/17193QuantityShort-runaveragecosts(dollars)AFCAVCAddverticallytoget...CostsGraphicallyPresented...2022/12/1378QuantityShort-run2022/12/17194QuantityShort-runaveragecosts(dollars)AFCAVCATCCostsGraphicallyPresented...2022/12/1379QuantityShort-run2022/12/17195QuantityShort-runaveragecosts(dollars)AFCAVCATCPlottingthechangesintotalcostyields...CostsGraphicallyPresented...2022/12/1380QuantityShort-run2022/12/17196QuantityShort-runaveragecosts(dollars)AFCAVCATCMCCostsGraphicallyPresented...2022/12/1381QuantityShort-run第三節(jié)長期成本理論5-3TheLong-runCostTheory第三節(jié)長期成本理論5-3TheLong-runCo2022/12/17198Long-runorShort-runCost？2022/12/1383Long-runorShort-2022/12/17199LTC曲線、LAC曲線和LMC曲線總成本平均成本邊際成本產(chǎn)量產(chǎn)量（a）（b）0LACLMCLTC2022/12/1384LTC曲線、LAC曲線和LMC曲線總一、LTC函數(shù)和LTC曲線由長期生產(chǎn)函數(shù)和成本方程，得一、LTC函數(shù)和LTC曲線由長期生產(chǎn)函數(shù)和成本方程，最優(yōu)生產(chǎn)規(guī)模選擇和LTC曲線每條STC曲線代表一種生產(chǎn)規(guī)模。a、b、c是STC曲線與LTC曲線的切點(diǎn)，表示不同產(chǎn)量下的最低總成本。STC1STC2STC3LTC0QCdebacQ1Q2Q3最優(yōu)生產(chǎn)規(guī)模選擇和LTC曲線每條STC曲線代表一種生產(chǎn)規(guī)模。2022/12/17202LTC曲線LTC線是STC線的包絡(luò)線。包絡(luò)線（envelope-curve）是指LTC線把無數(shù)條STC線包圍起來的連線。在包絡(luò)線上，每一條STC線與LTC線不相交但相切。2022/12/1387LTC曲線LTC線是STC線的包絡(luò)線擴(kuò)展線和LTC曲線oA2A3A1KB1B2B3Low·OB3=r·OA3C50100150QE3E2E1擴(kuò)展線Ｑ1=50Ｑ3=150Ｑ2=100RLTCw·OB2=r·OA2w·OB1=r·OA1擴(kuò)展線和LTC曲線oA2A3A1KB1B2B3Low·OB32022/12/17204REVIEW：擴(kuò)展線和STCoLＱ1Ｑ2Ｑ3A2E3K3A3