上海财经大学中级微观经济学课程课件叶正茂第六章

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1、第六章一般均衡与第六章一般均衡与福利经济学福利经济学u在其他条件不变的情况下考察单个经济在其他条件不变的情况下考察单个经济单位或市场的分析就是局部均衡分析，单位或市场的分析就是局部均衡分析，所得到的有关理论属于局部均衡论的范所得到的有关理论属于局部均衡论的范畴。畴。u相对应的，将所有相互联系的各个市场相对应的，将所有相互联系的各个市场看成一个整体来加以研究而进行的分析看成一个整体来加以研究而进行的分析就是一般均衡分析，相应的理论就是一就是一般均衡分析，相应的理论就是一般均衡理论。般均衡理论。u一般均衡理论的基本思想是考察市场相一般均衡理论的基本思想是考察市场相关经济变量之间的相互联系。关经济变

2、量之间的相互联系。u主要解决的问题就是是否存在一系列价主要解决的问题就是是否存在一系列价格使所有市场同时处于均衡，即所谓的格使所有市场同时处于均衡，即所谓的一般均衡存在性问题。一般均衡存在性问题。u在研究这一问题的过程中，我们讨论福在研究这一问题的过程中，我们讨论福利经济学的两个基本定理。利经济学的两个基本定理。u我们仅考虑竞争市场的行为：每个消费我们仅考虑竞争市场的行为：每个消费者或生产者都接受既定的价格，并作出者或生产者都接受既定的价格，并作出最优的选择；最优的选择；u我们采用简化的方法：两个消费者和两我们采用简化的方法：两个消费者和两种商品；种商品；u我们分两个阶段来考察一般均衡问题我们

3、分两个阶段来考察一般均衡问题u1.纯交换纯交换u2.含生产行为的一般均衡模型含生产行为的一般均衡模型6.1交换交换ExchangeuTwo consumers, A and B.uTheir endowments of goods 1 and 2 are uE.g. uThe total quantities availableandandunits of good 1units of good 2.andareExchangeuEdgeworth and Bowley devised a diagram, called an Edgeworth box, to show all possib

4、le allocations of the available quantities of goods 1 and 2 between the two consumers.Starting an Edgeworth BoxStarting an Edgeworth BoxWidth = Starting an Edgeworth BoxWidth = Height =Starting an Edgeworth BoxWidth = Height =The dimensions ofthe box are thequantities availableof the goods.Feasible

5、Allocations可行的配置uWhat allocations of the 8 units of good 1 and the 6 units of good 2 are feasible?uHow can all of the feasible allocations be depicted by the Edgeworth box diagram?Feasible AllocationsuWhat allocations of the 8 units of good 1 and the 6 units of good 2 are feasible?uHow can all of th

6、e feasible allocations be depicted by the Edgeworth box diagram?uOne feasible allocation is the before-trade allocation; i.e. the endowment allocation.（初始的禀赋配置是一种可行的配置）Width = Height =The endowmentallocation isandThe Endowment AllocationWidth = Height =The Endowment AllocationOAOB68The Endowment All

7、ocationOAOB6846The Endowment AllocationOAOB684622The Endowment AllocationOAOB684622Theendowmentallocation（禀赋配置）（禀赋配置）The Endowment AllocationMore generally, The Endowment AllocationThe Endowment AllocationOAOBTheendowmentallocationOther Feasible Allocationsu denotes an allocation to consumer A.u den

8、otes an allocation to consumer B.uAn allocation is feasible if and only ifandFeasible ReallocationsOAOBFeasible ReallocationsOAOBFeasible ReallocationsuAll points in the box, including the boundary, represent feasible allocations of the combined endowments.Feasible ReallocationsuAll points in the bo

9、x, including the boundary, represent feasible allocations of the combined endowments.uWhich allocations will be blocked by one or both consumers?uWhich allocations make both consumers better off?Adding Preferences to the BoxOAFor consumer A.Adding Preferences to the BoxMore preferredFor consumer A.O

10、AAdding Preferences to the BoxFor consumer B.OBAdding Preferences to the BoxMore preferredFor consumer B.OBAdding Preferences to the BoxMore preferredFor consumer B.OBAdding Preferences to the BoxOAFor consumer A.Adding Preferences to the BoxOAOBEdgeworths BoxOAOBPareto-ImprovementuAn allocation of

11、the endowment that improves the welfare of a consumer without reducing the welfare of another is a Pareto-improving allocation.uWhere are the Pareto-improving allocations?Edgeworths BoxOAOBPareto-ImprovementsOAOBThe set of Pareto-improving allocationsPareto-ImprovementsuSince each consumer can refus

12、e to trade, the only possible outcomes from exchange are Pareto-improving allocations.uBut which particular Pareto-improving allocation will be the outcome of trade?Pareto-ImprovementsOAOBThe set of Pareto-improving reallocationsPareto-ImprovementsPareto-ImprovementsPareto-ImprovementsTradeimproves

13、bothAs and Bs welfares.This is a Pareto-improvementover the endowment allocation.Pareto-ImprovementsNew mutual gains-to-trade region is the set of all further Pareto- improving reallocations. Tradeimproves bothAs and Bs welfares.This is a Pareto-improvementover the endowment allocation.Pareto-Improv

14、ementsFurther trade cannot improve both A and Bs welfares.Pareto-OptimalityBetter forconsumer BBetter forconsumer APareto-OptimalityA is strictly better off but B is strictly worse offPareto-OptimalityA is strictly better off but B is strictly worse offB is strictly betteroff but A is strictlyworse

15、offPareto-OptimalityA is strictly better off but B is strictly worse offB is strictly betteroff but A is strictlyworse offBoth A andB are worseoffPareto-OptimalityA is strictly better off but B is strictly worse offB is strictly betteroff but A is strictlyworse offBoth Aand B are worse offBoth A and

16、B are worseoffPareto-OptimalityThe allocation isPareto-optimal since theonly way one consumerswelfare can be increased is todecrease the welfare of the otherconsumer.Pareto-OptimalityThe allocation isPareto-optimal since theonly way one consumerswelfare can be increased is todecrease the welfare of

17、the otherconsumer.An allocation where convexindifference curves are “only just back-to-back” is Pareto-optimal.Pareto-OptimalityuWhere are all of the Pareto-optimal allocations of the endowment?Pareto-OptimalityOAOBPareto-OptimalityOAOBAll the allocations marked bya are Pareto-optimal.Pareto-Optimal

18、ityuThe contract curve（契约曲线） is the set of all Pareto-optimal allocations.Pareto-OptimalityOAOBAll the allocations marked bya are Pareto-optimal.The contract curveu契约曲线应该包括契约曲线应该包括OA和和OB这两个原点。这两个原点。u见书上见书上443页图页图30.2Pareto-OptimalityuBut to which of the many allocations on the contract curve will co

19、nsumers trade?uThat depends upon how trade is conducted.uIn perfectly competitive markets? By one-on-one bargaining?The CoreOAOBThe set of Pareto-improving reallocationsThe Core（交易的核）OAOBThe CoreOAOBPareto-optimal trades blocked by BPareto-optimal trades blocked by AOAOBPareto-optimal trades not blo

20、cked by A or BOAOBPareto-optimal trades not blocked by A or B are the core.The CoreuThe core is the set of all Pareto-optimal allocations that are welfare-improving for both consumers relative to their own endowments.uRational trade should achieve a core allocation.The CoreuBut which core allocation

21、?uAgain, that depends upon the manner in which trade is conducted.Trade in Competitive MarketsuConsider trade in perfectly competitive markets.uEach consumer is a price-taker trying to maximize her own utility given p1, p2 and her own endowment. That is, .Trade in Competitive MarketsOAFor consumer A

22、.Trade in Competitive MarketsuSo given p1 and p2, consumer As net demands for commodities 1 and 2 areandTrade in Competitive MarketsuAnd, similarly, for consumer B Trade in Competitive MarketsFor consumer B.OBTrade in Competitive MarketsuSo given p1 and p2, consumer Bs net demands for commodities 1

23、and 2 areandTrade in Competitive MarketsuA general equilibrium occurs when prices p1 and p2 cause both the markets for commodities 1 and 2 to clear; i.e.andTrade in Competitive MarketsOAOBOAOBCan this PO allocation beachieved?OAOBBudget constraint for consumer AOAOBBudget constraint for consumer ATr

24、ade in Competitive MarketsOAOBBudget constraint for consumer BTrade in Competitive MarketsOAOBBudget constraint for consumer BTrade in Competitive MarketsOAOBButTrade in Competitive MarketsOAOBandTrade in Competitive MarketsuSo at the given prices p1 and p2 there is an excess supply of commodity 1 e

25、xcess demand for commodity 2.uNeither market clears so the prices p1 and p2 do not cause a general equilibrium.OAOB此时，此时，So this PO allocation Cannot be achieved .OAOBWhich PO allocations can beachieved by competitive trading?Trade in Competitive MarketsuSince there is an excess demand for commodity

26、 2, p2 will rise.uSince there is an excess supply of commodity 1, p1 will fall.uThe slope of the budget constraints is - p1/p2 so the budget constraints will pivot （转动）about the endowment point and become less steep.Trade in Competitive MarketsOAOBWhich PO allocations can beachieved by competitive t

27、rading?Trade in Competitive MarketsOAOBWhich PO allocations can beachieved by competitive trading?Trade in Competitive MarketsOAOBWhich PO allocations can beachieved by competitive trading?OAOBBudget constraint for consumer AOAOBBudget constraint for consumer ATrade in Competitive MarketsOAOBBudget

28、constraint for consumer BTrade in Competitive MarketsOAOBBudget constraint for consumer BTrade in Competitive MarketsOAOBSoTrade in Competitive MarketsOAOBandTrade in Competitive MarketsuAt the new prices p1 and p2 both markets clear; there is a general equilibrium.uTrading in competitive markets ac

29、hieves a particular Pareto-optimal allocation of the endowments.uThis is an example of the First Fundamental Theorem of Welfare Economics.First Fundamental Theorem of Welfare EconomicsuGiven that consumers preferences are well-behaved, trading in perfectly competitive markets implements a Pareto-opt

30、imal allocation of the economys endowment.u福利经济学第一定理：福利经济学第一定理：u竞争的均衡是帕累托有效率的。竞争的均衡是帕累托有效率的。u证明见书上证明见书上452页。页。u福利经济学第一定理的暗含条件：福利经济学第一定理的暗含条件：u1、没有外部性、没有外部性u2、存在足够多的交易者以确保每个人致、存在足够多的交易者以确保每个人致力于竞争。力于竞争。Second Fundamental Theorem of Welfare EconomicsuThe First Theorem is followed by a second that stat

31、es that any Pareto-optimal allocation (i.e. any point on the contract curve) can be achieved by trading in competitive markets provided that endowments are first appropriately rearranged amongst the consumers.u福利经济学第二定理：福利经济学第二定理：u认为在一定条件下，每一帕累托有效配认为在一定条件下，每一帕累托有效配置均能达到竞争均衡。置均能达到竞争均衡。u即如果所有交易者的偏好呈凸性

32、，则每即如果所有交易者的偏好呈凸性，则每一帕累托有效配置均能达到竞争均衡。一帕累托有效配置均能达到竞争均衡。uGiven that consumers preferences are well-behaved, for any Pareto-optimal allocation there are prices and an allocation of the total endowment that makes the Pareto-optimal allocation implementable by trading in competitive markets.Second Fundam

33、ental Theorem of Welfare EconomicsSecond Fundamental TheoremOAOBThe contract curveSecond Fundamental TheoremOAOBSecond Fundamental TheoremOAOBImplemented by competitivetrading from the endowment w w.Second Fundamental TheoremOAOBCan this allocation be implementedby competitive trading from w w?Secon

34、d Fundamental TheoremOAOBCan this allocation be implementedby competitive trading from w w? No.Second Fundamental TheoremOAOBBut this allocation is implementedby competitive trading from q q.u福利经济学第二定理的含义：福利经济学第二定理的含义：u福利经济学第二定理意指分配与效率问福利经济学第二定理意指分配与效率问题可以分开来考虑。题可以分开来考虑。u市场机制在分配上是中性的。市场机制在分配上是中性的。Wa

35、lras LawuWalras Law is an identity; i.e. a statement that is true for any positive prices (p1,p2), whether these are equilibrium prices or not.Walras LawuEvery consumers preferences are well-behaved so, for any positive prices (p1,p2), each consumer spends all of his budget.uFor consumer A:For consu

36、mer B:Walras LawSumming givesWalras LawRearranged,That is, .Walras LawThis says that the summed marketvalue of excess demands is zero forany positive prices p1 and p2 - this is Walras Law.对于所有可能正的价格对于所有可能正的价格,总超额需求的值总超额需求的值恒为恒为0，称为瓦尔拉斯法则。，称为瓦尔拉斯法则。Implications of Walras LawSuppose the market for com

37、modity Ais in equilibrium; that is,ThenimpliesImplications of Walras LawSo one implication of Walras Law fora two-commodity exchange economyis that if one market is in equilibriumthen the other market must also be inequilibrium.Implications of Walras LawWhat if, for some positive prices p1 andp2, th

38、ere is an excess quantity suppliedof commodity 1? That is,ThenimpliesImplications of Walras LawSo a second implication of Walras Lawfor a two-commodity exchange economyis that an excess supply in one marketimplies an excess demand in the othermarket.uSuppose the market for commodity Auis in equilibr

39、ium；then the other market must also be in equilibrium.u一般地说，如果一般地说，如果k-1种商品是均衡的，那种商品是均衡的，那么第么第k种商品会自动均衡。种商品会自动均衡。相对价格与一般均衡的存在性u瓦尔拉斯法则表明，在瓦尔拉斯法则表明，在k种商品的一般均种商品的一般均衡模型中只存在着衡模型中只存在着k-1个独立方程式，即个独立方程式，即如果在如果在k-1个市场中需求与供给相等，那个市场中需求与供给相等，那么，最后一个市场的需求与供给必然相么，最后一个市场的需求与供给必然相等。等。u但我们可任选一种价格作为计价物，就但我们可任选一种价格作为

40、计价物，就只要求只要求k-1个相对价格。这样方程的个数个相对价格。这样方程的个数与未知数的个数相等。与未知数的个数相等。均衡的存在性u然而然而方程的个数与未知数的个数相等，就一方程的个数与未知数的个数相等，就一定有解吗？只有当总需求函数是连续函数就一定有解吗？只有当总需求函数是连续函数就一定有解。要么每个人的需求函数是连续函数或定有解。要么每个人的需求函数是连续函数或消费者的需求函数是不连续的，但只要这些消消费者的需求函数是不连续的，但只要这些消费者的人数相对小于市场的规模，总需求函数费者的人数相对小于市场的规模，总需求函数依然是连续的。依然是连续的。u据此，瓦尔拉斯一般均衡理论断言，基据此，

41、瓦尔拉斯一般均衡理论断言，基于局部均衡分析的一般均衡价格存在。于局部均衡分析的一般均衡价格存在。附录：交换的帕累托有效率配置附录：交换的帕累托有效率配置的条件的数学证明的条件的数学证明u交换的帕累托有效率配置的条件：交换的帕累托有效率配置的条件：uMRSA=MRSBu证明：对于证明：对于A、B两个消费者两个消费者u给定效用水给定效用水 U，当，当UB(XB,YB)=U时，求时，求A的的maxUA的条件。的条件。umaxUA (XA,YA)uS.t. UB(XB,YB)=UuXA +XB =X0（总量）（总量）uYA+YB= Y0（总量）（总量）uL UA (XA,YA)- UB(XB,YB)-

42、U- 1(XA +XB X0)- 2(YA +YB Y0)u L/ XA= UA/ XA- 1=0 u L/ YA= UA/ YA- 2=0 u L/ XB=- UA/ XB- 1=0 u L/ YB=- UB/ YB- 2=0 u MRSXYA=( UA/ XA)/( UA/ YA)u = 1/ 2u MRSXYB=( UB/ XB)/( UB/ YB)u = 1/ 2u 得证。得证。6.2 生产生产ProductionExchange Economies (revisited)u在上节里，我们讨论了在上节里，我们讨论了uNo production, only endowments, so

43、no description of how resources are converted to consumables.uGeneral equilibrium: all markets clear simultaneously.u1st and 2nd Fundamental Theorems of Welfare Economics.u下考虑生产继续讨论下考虑生产继续讨论Now Add Production .uAdd input markets, output markets, describe firms technologies, the distributions of firm

44、s outputs and profits Now Add Production .uAdd input markets, output markets, describe firms technologies, the distributions of firms outputs and profits Thats not easy!Robinson Crusoes EconomyuOne agent, RC.uEndowed with a fixed quantity of one resource - 24 hours.uUse time for labor (production) o

45、r leisure (consumption).uLabor time = L. Leisure time = 24 - L.uWhat will RC choose?Robinson Crusoes TechnologyuTechnology: Labor produces output (coconuts) according to a concave（凹的）production function.Robinson Crusoes TechnologyProduction functionLabor (hours)Coconuts240Robinson Crusoes Technology

46、Labor (hours)CoconutsProduction function240Feasible productionplansRobinson Crusoes PreferencesuRCs preferences:coconut is a goodleisure is a goodRobinson Crusoes PreferencesLeisure (hours)CoconutsMore preferred240Robinson Crusoes PreferencesLeisure (hours)CoconutsMore preferred240Robinson Crusoes C

47、hoiceLabor (hours)CoconutsFeasible productionplansProduction function240Robinson Crusoes ChoiceLabor (hours)CoconutsFeasible productionplansProduction function240Leisure (hours)240Robinson Crusoes ChoiceLabor (hours)CoconutsFeasible productionplansProduction function240Leisure (hours)240Robinson Cru

48、soes ChoiceLabor (hours)CoconutsFeasible productionplansProduction function240Leisure (hours)240Robinson Crusoes ChoiceLabor (hours)CoconutsProduction function240Leisure (hours)240C*L*Robinson Crusoes ChoiceLabor (hours)CoconutsProduction function240Leisure (hours)240C*L*LaborRobinson Crusoes Choice

49、Labor (hours)CoconutsProduction function240Leisure (hours)240C*L*LaborLeisureRobinson Crusoes ChoiceLabor (hours)CoconutsProduction function240Leisure (hours)240C*L*LaborLeisureOutputRobinson Crusoes ChoiceLabor (hours)CoconutsProduction function240Leisure (hours)240C*L*LaborLeisure商品的边际替代率商品的边际替代率M

50、RS = MPLOutputRobinson Crusoe as a FirmuNow suppose RC is both a utility-maximizing consumer and a profit-maximizing firm.uUse coconuts as the numeraire good; i.e. price of a coconut = $1.uRCs wage rate is w.uCoconut output level is C.Robinson Crusoe as a FirmuRCs firms profit is = C - wL.u = C - wL

51、 C = + wL, the equation of an isoprofit line.uSlope = + w .uIntercept = .Isoprofit LinesLabor (hours)Coconuts24Higher profit; Slopes = + w0Profit-MaximizationLabor (hours)CoconutsFeasible productionplansProduction function240Profit-MaximizationLabor (hours)CoconutsProduction function240Profit-Maximi

52、zationLabor (hours)CoconutsProduction function240Profit-MaximizationLabor (hours)CoconutsProduction function24C*L*0Profit-MaximizationLabor (hours)CoconutsProduction function24C*L*Isoprofit slope = production function slope0Profit-MaximizationLabor (hours)CoconutsProduction function24C*L*Isoprofit s

53、lope = production function slope i.e. w = MPL0Profit-MaximizationLabor (hours)CoconutsProduction function24C*L*Isoprofit slope = production function slope i.e. w = MPL = 1 MPL = MRPL.0Profit-MaximizationLabor (hours)CoconutsProduction function24C*L*Isoprofit slope = production function slope i.e. w

54、= MPL = 1 MPL = MRPL.RC gets 0Profit-MaximizationLabor (hours)CoconutsProduction function24C*L*Isoprofit slope = production function slope i.e. w = MPL = 1 MPL = MRPL.Given w, RCs firms quantitydemanded of labor is L*LabordemandRC gets 0Profit-MaximizationLabor (hours)CoconutsProduction function24C*

55、L*Isoprofit slope = production function slope i.e. w = MPL = 1 MPL = MRPL.Given w, RCs firms quantitydemanded of labor is L* andoutput quantity supplied is C*.LabordemandOutputsupplyRC gets 0Utility-MaximizationuNow consider RC as a consumer endowed with $* who can work for $w per hour.uWhat is RCs

56、most preferred consumption bundle?uBudget constraint isUtility-MaximizationLabor (hours)Coconuts240Budget constraintUtility-MaximizationLabor (hours)Coconuts240Budget constraint; slope = wUtility-MaximizationLabor (hours)CoconutsMore preferred240Utility-MaximizationLabor (hours)Coconuts240Budget con

57、straint; slope = wUtility-MaximizationLabor (hours)CoconutsBudget constraint; slope = w240Utility-MaximizationLabor (hours)Coconuts240C*L*Budget constraint; slope = wUtility-MaximizationLabor (hours)Coconuts240C*L*MRS = wBudget constraint; slope = wUtility-MaximizationLabor (hours)Coconuts240C*L*Lab

58、orsupplyBudget constraint; slope = wMRS = wGiven w, RCs quantitysupplied of labor is L*Utility-MaximizationLabor (hours)Coconuts240C*L*Given w, RCs quantitysupplied of labor is L* andoutput quantity demanded is C*.LaborsupplyOutputdemandBudget constraint; slope = wMRS = wUtility-Maximization & Profi

59、t-MaximizationuProfit-maximization: w = MPLquantity of output supplied = C*quantity of labor demanded = L*Utility-Maximization & Profit-MaximizationuProfit-maximization: w = MPLquantity of output supplied = C*quantity of labor demanded = L*uUtility-maximization: w = MRSquantity of output demanded =

60、C*quantity of labor supplied = L*Utility-Maximization & Profit-MaximizationuProfit-maximization: w = MPLquantity of output supplied = C*quantity of labor demanded = L*uUtility-maximization: w = MRSquantity of output demanded = C*quantity of labor supplied = L*Coconut and labormarkets both clear.Util

61、ity-Maximization & Profit-MaximizationLabor (hours)Coconuts24C*L*0MRS = w = MPLGiven w, RCs quantitysupplied of labor = quantitydemanded of labor = L* andoutput quantity demanded =output quantity supplied = C*.First Fundamental Theorem of Welfare Economicsu所以结合生产，福利经济学第一定理仍然是成立的。uA competitive marke

62、t equilibrium is Pareto efficient ifconsumers preferences are convex （凸状）there are no externalities in consumption or production.Second Fundamental Theorem of Welfare EconomicsuAny Pareto efficient economic state can be achieved as a competitive market equilibrium ifconsumers preferences are convexf

63、irms technologies are convex（凸状）there are no externalities in consumption or production.Production PossibilitiesuResource and technological limitations restrict what an economy can produce.uThe set of all feasible output bundles is the economys production possibility set.uThe sets outer boundary is

64、the production possibility frontier.Production PossibilitiesFishCoconutsProduction possibility frontier (ppf)Production PossibilitiesFishCoconutsProduction possibility frontier (ppf)Production possibility setProduction PossibilitiesFishCoconutsFeasible butinefficientProduction PossibilitiesFishCocon

65、utsFeasible butinefficientFeasible and efficientProduction PossibilitiesFishCoconutsFeasible butinefficientFeasible and efficientInfeasibleProduction PossibilitiesFishCoconutsPpfs slope is the marginal rateof product transformation.Production PossibilitiesFishCoconutsPpfs slope is the marginal rateo

66、f product transformation.Increasingly negative MRPT increasing opportunitycost to specialization.Coordinating Production & ConsumptionuThe ppf contains many technically efficient output bundles.uWhich are Pareto efficient for consumers?Coordinating Production & ConsumptionFishCoconutsORCOMFDecentral

67、ized Coordination of Production & ConsumptionFishCoconutsORCOMFCompetitive markets, utility-maximization and profit- maximization 生产与交换均达到帕累托有效配置的条件的数学证明u1、生产与交换均达到帕累托有效配置的条件uMRS=MRPT或或MRTu2、证明见478页-479页的附录6.3 福利福利 WelfareSocial Optima & EfficiencyuAny social optimal allocation must be Pareto optima

68、l.uWhy?uIf not, then somebodys utility can be increased without reducing anyone elses utility; i.e. social suboptimality inefficiency.u新的配置必然有更高的福利，这与开始假新的配置必然有更高的福利，这与开始假定的福利最大化矛盾。定的福利最大化矛盾。u因此福利最大化的配置必须是帕累托有效因此福利最大化的配置必须是帕累托有效率配置。率配置。u结合上节的内容，我们可以得到以下结论：见书上486页。u所有的福利最大化都是竞争均衡，且所所有的福利最大化都是竞争均衡，且所有

69、的竞争均衡都是某一福利函数的福利有的竞争均衡都是某一福利函数的福利最大化。最大化。Fair Allocations公平配置公平配置=平等配置平等配置+帕累托效率帕累托效率Fair AllocationsOAOBPost-tradeallocation -is it fair?Post-trade allocation is Pareto-efficient andenvy-free; hence it is fair.u市场机制将保持某种平等性：市场机制将保持某种平等性：u如果最初配置是平等分配，那么通过市如果最初配置是平等分配，那么通过市场机制的最终配置一定是公平的。场机制的最终配置一定是公平的。u或者说，来自平等分配的竞争均衡必然或者说，来自平等分配的竞争均衡必然是一个公平配置。是一个公平配置。本文来自网络，请不要使用盗版文档，尊重作者的辛苦劳动，谢谢G我爱朱丹老婆20100808080808080808080808080808080808080808080808080808080808080Lvdd我爱你ZDLP